Street Lethal

iTrader: (16)

Essentially, it isn't the idle RPM itself that causes any compressor surge. It's decel at any given point in time, because it took an increased throttle to bring it to that point, and this is when pressure buildup of course occurs, as you know. Joe is running a vented blow off valve that is bleeding at 10" of vacuum or less, when he should be recirculating the air back to the intake tract, not venting to the atmosphere. He is emulating a bypass valve at idle only halfway. This is why he is losing boost pressure. The noises he is referring to in terms of surge, the explanations of how things are supposed to work that he is quoting from others, etc, is all a deterrence as to what he needs to do. There is no video of the surge he is referring to that I have seen, and a vented BOV at 10" of vacuum will not allow any blower to maximize its' boost pressure setting via predetermined pulley sizes...

Diggler is right though, he needs a bypass valve.

... and Joe, a centrifugal blower is not fixed, a roots blower is.

- Rob

anesthes

iTrader: (12)

You shouldn't ever recirculate air back into the intake tract. That's done to make MAF sensors happy. The last thing you want to do is add heated air back into the blower to get even more heated.

The boost pressure is being lost because the valve is opening, probably because it's broken.

Listen to this video from last year. Tell me what you hear:


A roots blower is a positive displacement as in it pushes a predetermined volume of air per RPM, correct. I'm saying the impeller is FIXED as in slows down and speeds up directly in relation to the crank (unless you have belt slip, which is not intentional).

EDIT: Watch the video. The third time I do it, watch the intake pipe move around. That is because the air is hitting the throttle blades. You can hear the compressor surge even though the BOV is open, which is another issue, the BOV appears to not be large enough for the volume of air.

I've run DSM style blow off valves since the late 90s on these vortech blowers and never had a problem. I suspect this BOV is just broken.

-- Joe

Street Lethal

iTrader: (16)

That is not true. We recirculate the air at idle to relieve any possible resistance dependent on blower selection, pulley size, and engine efficiency. Nothing to do with MAF. That is how a bypass valve works, it remains open at idle while recirculating air back to the intake tract to allow for the compressor to "freewheel" if it needs to for longevity (like a ported compressor housing), closes under boost, then opens during decel to again increase the units longevity. No boost loss whatsoever in this case, unlike a vented BOV to the atmosphere that is opening way ahead of schedule. In fact, boost can be controlled with a bypass valve if need be.

Also, in terms of heat from the air, what heat are you referring to? There is no boost resistance at idle, so no increased IAT temps, which equates to no heat rise. Now, as far as boost relative to positive displacement vs centrifugal, it is measured entirely different. The latter is squared Joe, it is not fixed. It only "seems": fixed because of the predetermined pulley sizes, but increased RPM will give you more boost pressure, because again, it is squared... just like a turbo.

- Rob

Street Lethal

iTrader: (16)

I hear a compressor chopping air at idle (spool), normal.

I hear a BOV venting pressure buildup when throttle is increased then suddenly closed, normal.

We call it horse sneeze, it is normal. That's not compressor surge, which would break the unit.

- Rob

anesthes

iTrader: (12)

Recirculating hot air is stupid.. People with draw through MAF have to do it because it's already been measured. If you don't have to do it, why would you do it?

You can call it a bypass, a bov, or a hosie-whats-it. The desired operation is to be open pretty much all the time unless attempting to actually make boost (lots of throttle).

Why would you want hot air back in your intake to be re-compressed again ??


Why does it matter where the air goes ? It opening 'ahead of schedule' is because it's broken, not because it's vented to atmosphere.

Are you high? Have you ever pointed an IR gun at the outlet temp of a blower? It's hot, from previously compressing, from friction, from hot oil. It's hot.. .Very hot.

It's fixed because it's a fixed ratio.. You can arrive at airflow vs impeller speed, just like a turbo, but unlike a turbo I know exactly what my impeller speed is at a given RPM.

At the end of the day, I don't really care much about boost in terms of a number, but rather my immediate concern is 'where the hell is it going'. The math indicates that there is a leak, my ears indicate that there is a leak. And I'm not entirely ruling out belt slipping either, although there is no evidence of that (belt dust).

The way I see it, the BOV is broken or just not right for the application. I have the following problems:

1) It's not opening when it should (idle)
2) It's opening when it shouldn't (wide open throttle)
3) Even when open it's now dumping ENOUGH VOLUME of air, so the compressor is still surging (watch the video) probably because it's made for those little hair dryer turbos that don't flow much.

My buddy gave it to me. I should have thrown it away. My bad.

-- Joe

anesthes

iTrader: (12)

Lol that's not normal.. I've been running these blowers for 20 years. You need to stop hanging out with the turbo ***** boys. Normal is a loud dump of air, not a fluctuating rythim as the impeller tries to go backwards lol.

And honestly, I care more about breaking a $3,400 head unit than I would a $300 ebay turbo.

-- Joe

Street Lethal

iTrader: (16)

Judging from what I am reading, and putting everything else to the side because we obviously see things differently, it sounds like there are two complaints to the original issue;

* What you think is compressor surge...
* Boost Loss...

The noise you hear when you blip the throttle is not compressor surge, it is the vented air "skipping" because the BOV is too small, which is nicknamed horse sneeze. A larger BOV will give you the smoother sounding vented air that you prefer which would be all in one breath. If the compressor itself was surging, you would know it, because the blower would momentarily lock, cause a bog, and possibly throw the belt.

A bypass valve will fix your boost loss issues. Get rid of the vented to the atmosphere BOV, it does more harm than good. Either that or just set it to open during decel, not during idle vacuum. This is my opinion regarding the issue(s) you're experiencing. I opted for the P1X Procharger with my new Camaro w/4 valve per cylinder LGX engine, and there is no way I will run a vented BOV at idle...

- Rob

86CamaroDan

1) I agree with Joe on this one. recirculating bypass valve is for MAF systems only as it has previously measured the air, IF the MAF is on the blower inlet. a 2011 Camaro I did has it in the intercooler outlet so that type of system is exempt from that because its being vented before the MAF reads it.
2)After a good drive, my blower gets so hot you cant touch it, so outlet temps are pretty warm. I wouldnt say hot, but easily warmer than ambient.
3) I suspect your BOV is incorrect spring pressure, and too small for your application. I think you will be happy with the Tial unit. (sounds bitchin too)

Street Lethal

iTrader: (16)

Dan think of what you're saying. A bypass valve is only meant to relieve the compressor from backpressure, that is its' only function. People vent to the atmosphere, aka BOV, for no other reasoning than for sound. A bypass valve recirculates the charge for that very reason, to keep the compressor free wheeling as much as possible, and to keep the boost there during shifting. If bypass valves were MAF specific, then every Grand National would have come with one from the factory. Alas no bypass valve, and no BOV for the Grand National. It seems some of what is being said is being parroted from what was wrongly thought of years and years ago...

- Rob

Street Lethal

iTrader: (16)

Let's end this debate with what I asked earlier. Supercharged guys, plug your BOV, and tell the thread how much boost you are seeing at idle with it forced closed. Hell, give it some throttle while you're at it, and tell the thread when (at what RPM) you see 1-psi of boost pressure. This right here will tell you if you need a vented BOV at idle. No need to mash the throttle, just a small and easy test to confirm what you guys believe to be true...

- Rob

Street Lethal

iTrader: (16)

You can calculate boost pressure via pulleys using Vortech's calculator, and once your final boost pressure is derived at a specific RPM for your application, then tell me how a vented BOV at 10" of vacuum will not affect that very boost pressure? There is no way any of you are seeing boost pressure at idle with the blower running straight to the throttle body, that is impossible with a centrifugal supercharger on a healthy SBC, unless maybe it is powering an iron duke four banger that has absolutely no flow to begin with. If you are convincing yourself that you need your BOV to open at 10" of vacuum (from a stable 15" of idle vacuum), then what is the point of venting it to atmosphere? You're inadvertently killing performance. Even a bypass valve closes at part throttle. So why do it? You're worried about IAT's? Hmm, and here most are saying the turbo applications are different, when it is turbo applications that are more concerned with IAT's and EGT's. You would want that pressure at part throttle, and you would want to vent that pressure during decel only. That is why I asked what your kPa was at idle with the BOV plugged, as it sounds like you are telling yourselves that it is borderline 100-kPa. Impossible.

- Rob

86CamaroDan

Correct. I agree 100%
Bypass valves are installed to revert back to the intake charge pipe after the MAF so its not a infinite loop of incomming air. This shouldnt help keep intake pressure up as its before the blower/turbo. (That would completely counter the whole purpouse of it. I guess i should say vehicles who have been converterd to speed density or already are can use a BOV over a bypass valve because theres no measurement device for incomming air. Thats why Joe and I can use BOV's - Were both speed density - Measurement is taken at the intake for load.
Thats quite intresting that they dont use anything from the factory. Maybe they didnt think it was a issue back then? Edit: PS are you sure they dont have one built into the compressor side like some of the mitsubishi turbos?

Street Lethal

iTrader: (16)

They run internal wastegates on the hot side that only opens during boost, stock spring is rated at 4-5 pounds, but the compressor on the cold side is still relegated to backpressure when the throttle blades suddenly close, and 4-5psi is pretty substantial. But again, the compressor wheels bleed boost at slower speeds, as do torque converters when lower RPM's are reached. Don't forget about the IAC in which remains open after decel, What changed everything was the ported compressor housings, which allowed GN guys to step it up without the need for a BOV.

Don't get me wrong, some GN guys will play with a BOV, but we only ever seen them being used, or mandatory for that matter, on manual cars (EVO, STI, etc.) to maintain boost pressure during shifts while rallying (by that I mean they are plumbed into the intake much like a bypass valve, but with the added noise that those guys love to hear). It's rare to find a BOV being needed on an automatic unless it is one of those youtube nutcases running a 102mm sized turbo charger. Normally things should be adequately sized. Then again in Joe's case, it sounds like he is trying to find a happy 5-6psi boost pressure medium because of his higher static compression, and cast internals, so he is playing with the BOV to achieve his desired results. Doesn't work that way though. Kinda like, hmm, I got me a F3 Procharger, now to install in onto my bolt on L98 and control it with a vented BOV...

- Rob

anesthes

iTrader: (12)

It's skipping because the BOV is too small, I agree, but that IS surge. It's trying to stop the blades which is why it also farts OUT THE AIR CLEANER. If I were to guess and had a high speed camera, I would guess it probably pulses out the bov and air cleaner back and forth.

Yes I need a larger BOV. It doesn't 'lock because air compresses thankfully.. If it was a fluid such as water, things would be different...

How ?? You have yet to explain that.

That's not a reasonable scientific experiment because you won't see pressure in the intake because the throttle is closed and the IAC will fully extend. Even if you did manage to get more air into the engine that it needed, the idle speed would simply increase. You will never see boost pressure.

What you may see is an increase in pressure between the discharge tube and the throttle blades, although I suspect not.



It won't, because the second you go to WOT intake vac goes to zero because it's an internal combustion engine.

I think I just realized where you are confused on this.. A lot of turbo cars and diesels do make boost part throttle and even very light throttle under load. This is because the expanding exhaust gasses are spinning the turbine, so you might have an impeller speed of 80,000 RPM at just 2100 RPM crank speed on a turbo.. That is never ever ever going to happen on a supercharged car. You probably don't have any experience with a supercharged engine.

You didn't understand what I said.

A bypass valve is REQUIRED if you are running a DRAW THROUGH MAF and you wish to dump excess boost on throttle close, because you already measured the air. Grand nationals don't have any type of valve to dump boost. Nothing.

Nobody is parroting anything. The science is fairly simple.

Can you explain why a bypass is better than a BOV on a speed density application? I've explained why it's a stupid idea, in my opinion.

-- Joe

anesthes

iTrader: (12)

For context, my T-trim is 83.56mm and Dan's is 78.74mm

-- Joe

Kingtal0n

The type-S diaphragm is bad or the unit is seizing up due to corrosion/age

just confirming it will be better with proper bypass,
and always remember you can run a twin bypass if one isn't enough.
In that video I can hear the lazy note of the malfunctioning type-S (kind of a long drawn out whine) where it should be more sharp and characteristic
and the compressor chop/surge forcing air backwards through the impeller attempting to damage the sealing spaces, and agree you never want to hear that noise in normal operation.

bypass valves are intended to protect the compressor by releasing pressure on the compressor outlet tube, they do not maintain boost pressure because they release pressure by design.
The way I would infer that a bypass valve somehow 'preserves' boost pressure is by relating the impeller speed to various engine conditions. For example at idle an open bypass recirculated to the intake tract will allow a higher steady state impeller rpm than a system with an atmospheric bypass. By default this must be true since kinetic energy which was imparted to the air by action of force from the blades, has been preserved and fed back into the intake tract, and with heating of the air recurrently also, more energy has been preserved by a re-circulation tube, fuel efficiency should be increased slightly (not much, maybe 0.2%?) and impeller rpm has been increased slightly, making this the most desirable bypass configuration in turbo applications where impeller RPM might be increased via 'energy scavenging' during bypass situations, which means less delay "lag" when trying to move back to boost condition.
In comparison, if we vent bypass to the atmosphere, impeller rpm should drop at idle steady state because the heated, kinetically charged air is leaving the system.
And of course if we remove the bypass completely now impeller rpm will be lowest, and may even surge at idle steady state (steady chop as the air has nowhere to go). This condition is the worst possible thing you can do to a compressor because the constant abuse to the sealing surfaces wears them out, as friction from air molecules constantly collide awkwardly with the seals wherever they are. And there are always sealing space.

Also the reason roots blowers dont need bypass valves at idle is because they take constant gulps of air thats already been strongly forced into a vacuum by the throttle blades. Only blowers which take full gulps of the atmosphere will require bypass.

Street Lethal

iTrader: (16)

... and mine is approximately 76mm, and makes way more boost than yours at part throttle. Would you like to compare how fast mine spins to yours during load and at what RPM lol? Would you like to know why my turbo does not experience compressor surge when the throttle blades suddenly close even without a BOV? Horse sneeze is not compressor surge, and if your blower is surging with an engine that, allegedly, makes 500 HP naturally aspirated, off idle and under a 2000-RPM blip, then you don't quite understand what compressor surge is. How much cfm is your blower moving at 800-RPM through 2000-RPM? I'll be waiting for that answer. Show me the sudden surge (bog) in the log when the blower momentarily locks, because I sure as hell didn't see that in the video.

- Rob

Street Lethal

iTrader: (16)

Joe, power adders work against resistance. No resistance, no boost, no added benefit. A blower works against resistance when it see's boost pressure. Five, Ten, Twenty pounds of boost is not surge, it is resistance. When the throttle blades suddenly close, there is again resistance, and the noise you hear through the BOV is the blower following through that resistance. It is not going back and forth as if it were surging, the blower is forcing the charge out of the BOV, and horse sneeze is due to the smaller BOV size that you chose. But that does not mean it is surging. The compressor surges when it loses momentum, it is being forced back, and it will slow the engine down! Just because you hear horse sneeze does not mean the blower is being slowed down, it see's the same resistance when in boost! I don't think you know what compressor surge really is, as it sure as hell does not happen under 2000-RPM when it is still out of boost lol...

- Rob

86CamaroDan

Centrifugal blowers dont make any boost at part throttle, bypass valve is open

I dont think your having compressor surge, i think its a burst of pressure through a smaller than ideal BOV

Kingtal0n

A blower can only do one of two things when spun correctly (to the 'correct' rpm ranges). It can flow properly to match the flow-rate of the engine at the given pressure ratio, or it can surge if the flow rate at the given pressure ratio required to maintain that flow isn't intended as a real operating state (its not found on the compressor map and falls somewhere to the left of the surge line).

What is being suggested is that a blower is doing this other, third thing, which nobody has ever heard of, making 'surge like noises' but not actually surging. Which must be incorrect since we know they can only do one of two things.

Even if we ignore the compressor flow data and the fact that all atmospheric driven blowers have leftover flow-rate at idle (or else their belt ratio doesn't make sense) to discharge and that if the discharge isn't properly handled the compressor will surge (the definition of passing a surge line is when the compressor flow rate exceeds the flow rate of the engine at the given pressure ratio required to maintain that flow rate.)

There are still warnings on the manufacturers website about friction and reduced blower performance when not having an (sufficient) bypass setup, which only confirms the fact that they are surging. There is no other condition which would undoubtedly heat the air and blower, due to friction, going on inside any blower.

Street Lethal

iTrader: (16)

You know what it is, it comes down to what his definition of compressor surge is. We'll hear things like horse sneeze, or flutter, which is nothing more than a momentary stall of the vented charge because of the inadequate BOV and intake tube size, but remember that the blower is still spinning as this is happening, and the BOV is sharing that vented charge with the IAC which is still open, so it is alleviated pretty quick. Then there is real compressor surge caused by serious over boosting and high RPM, which happens way way above 2000-RPM, and this will also happen at full throttle as well as decel, which is called open throttle surge. That's when you know the blower is way too big. Don't get me wrong, Joe has every right to be concerned because its an investment, but that noise won't hurt his blower in terms of the back pressure actually spinning it backwards a tad, especially at that RPM in the video. The charge would bleed off of the wheels (ported housings mimic this and takes the place of the wheel), in conjunction with the BOV and IAC also relieving the pressure because both are open. It would take a giant blower that is pulley'd to the moon, at 5000-RPM plus to separate a blower from its' casing. But even then, if you're not running a cog setup, the slipping belt should technically save it...

- Rob

86CamaroDan

Blower is always spinning, throttle is cracked, and atleast on my megasquirt the IAC closes above 1800 RPM, but between the throttle and open BPV yes, its alleviated.

Agreed. Better safe than sorry. Cheap insurance.

Im not even sold on the compressor surge with blowers in general to be honest (unless its belt slip which is causing a similar type sound?). If anything it would have to be a heavy backfire to get it to spin backwards and thats only if your running a serpentine belt drive.

Kingtal0n

I've heard similar arguments from turbo crowd whos main response was "I won't actually ever put 50k miles on the turbo"

Basically they are saying that even if minor surge takes its toll over time, they won't own the turbo long enough to experience significant deterioration.

Funny though, that is the same excuse the built engine crowd uses to defend poorly built engines.

Anyways. SO this is technically true- you can buy a brand new turbo car, strip the bypass, and run it for 50k without much if any deterioration in power for that duration.
Because turbochargers are so well built obviously.

As mileage becomes 50-150k, I noticed the engines where the bypass or air filter was removed have poor condition turbochargers, with excess shaft play and chipped compressor wheels. Many turbochargers used with OEM bypass systems still look brand new even after 150-200k miles if an air filter was used.

Any surge is air molecules forced to 'scrub' friction with the sealing spaces and gradually ruin them. Even at idle there is no way I would want to 'sand blast' the insides of my supercharger with 'scrubbing air molecules'. I do believe that even at idle speeds, air can cut microscopic crevices in the materials and over time these add up to major leakage. Sort of like how cleaning your glasses on a regular shirt doesn't seem leave any scratches- because they are microscopic, and over time they add up to a foggy appearance in the glass, leaving you wondering "why did the glass get that way?" never realizing it was the infinite number of tiny scratches left behind over time from using the wrong material to clean them.

Kingtal0n

Surge is not the compressor spinning backwards. If the compressor could spin backwards instantly when it needed to there would be no surge.
Surge is the compressor continuing to spin forwards even when the impeller speed cannot support the flow rate at the given or required pressure ratio.
Perhaps a better way to visualize surge is to watch a compressor wheel speed log and maf signal during a surge situation.
The maf signal will look like a series of spikes in flow rate, as the compressor wheel repeatedly loses its 'grip' on air molecules as they slip backwards into the pre-compressor tube where the maf is (flow "spikes" seen on the maf are the result of reversing air molecules flowing backwards through the compressor, since a maf reads "flow" in both directions.)

In surge, air molecules are slipping behind the blades, as opposed to being ejected from their tips. It puts a stress on the blade that wasn't intended for normal operation, a force in the 'wrong' direction, If I had to guess without seeing a model I would say the force would be in the opposite direction of the intended flow. So you would expect the wheel to be beefed up in both areas so it would tolerate both conditions.
However it is tough to say from an abstract point of view, as all blowers are not created equally. Some may have superior materials or looser clearances that tolerate higher levels of surge.
It is simply our duty to minimize the effects and possibilities of surge, that is all we can do

Street Lethal

iTrader: (16)

You know what's funny guys, everyone is so afraid of compressor surge when the unit itself was designed to take the pressure from both boost and back pressure applications. This is through countless testing in house. Yet a cheap, stock IAC valve, that was never meant for boosted applications mind you, experiences real surge on a constant basis, back and forth within vacuum, and now suddenly throw kPa into the mix, with its' tiny little shaft and pintle that was never balanced properly for that. If an IAC can take the pressure put out by this Vortech, I think it's safe to say the Vortech unit itself, which was designed for it, well, you get the gist of where I am going with this. Hell some of you guys are running thirty year old IAC's too lol. Just install a larger BOV and be done with it if you have your heart set on a vented BOV, just get a new/dead reliable one this time around...

- Rob

anesthes

iTrader: (12)

This would be a lot easier if you understood how these things work.

It's been explained several times.

-- Joe

anesthes

iTrader: (12)

The dead give away is the puff of air coming out of the air cleaner. The belt won't slip (or it shouldn't) so the blades won't spin backwards. The air has to go SOMEWHERE.

-- Joe

anesthes

iTrader: (12)

These are the same guys who put $300 ebay turbos on their Junkyard builds.

Like I said before, these head units are like $3,400 new, I'd like to minimize risk and use the proper valve.

That's a pretty good explanation of why Rob feels recirculation is better, but didn't actually understand why. He seems to be struggling with the fact that a Turbo impeller is going to spin at whatever RPM it wants vs a supercharger which has a fixed ratio with the crank RPM.

-- Joe

DIGGLER

iTrader: (1)

i just know the ysi car i work on is dumping a boatload of air out the bypass at idle. i also dont recall hearing that car make any kinds of blowoff sounds or whoochuchuchuchu sounds on decel out of its vortech mondo bypass valve. if the bypass was shut at idle, i would have to imagine some measureable amount of positive pressure in the charge pipe as well as added load on the blower and in turn crankshaft. probably the iac would need to be closed nearly 100% to get the idle down.
bypassing air back into the air intake/filter assy. i dont believe would cause any issue. while it is tossing slightly heated air back into the inlet, the only time it is doing so is while off the gas or at idle with zero boost and low impeller speeds. possible benefits would be preventing any unused methanol from an alky kit from misting on hot exhaust, and keeping dirt daubers from building nests in the bypass outlet since the whole system would be closed and filtered.

Kingtal0n

I'm glad we settled that the purpose of bypass tubes is to keep wasps from building nests in there
I'll have to re-use this somewhere, thanks...

But what about all the charged air molecules brah? Where do they go?
Catch and release?
meow

Street Lethal

iTrader: (16)

.... lol, the person you're quoting has been cutting and pasting information from the net since day one, why do you think the body of the text looks the way it does. Glad you find web information from him useful. As for me not understanding what you're saying, that is because you do not make any sense, and lets not forget that you're the only one here with a problem with your setup, nobody else. so you clearly have no idea what you're talking about Joe, and I tried very hard not to make you look like a fool by explaining it thoroughly, but you're doing a very good job by yourself with all of these questions with a build that should have hit the track already, and you still can't build boost, and/or you have a boost leak at idle allegedly. I mean how many times will you go over the "rules" at the track to buy you some time until you can at least go wide open throttle lmao. Again, if reading irrelevant words satisfies you, and if it makes sense, then apply them and fix your issue and make it happen already. Otherwise the words are meaningless because it did not fix anything, and you'll start another thread in the months to come saying the same damn thing. Other than entertainment, I don't see why anyone else would bother chiming in other than to cut and paste and try to make people view him as important . Hell that is the only reason why I bother in these posts, entertainment. Boredom. Let's see a track video from the guy you enjoy patting on the back while going nowhere lol, just like this thread. Not just a 2-5psi video on the street of him getting dusted lmao. Yes we know the car is driveable ten years later, but how fast is it lol. Hell I'll put my new Camaro naturally aspirated against both your cars, and neither of you will be that much ahead. So, umm, yeah, keep applauding yourselves while nothing is accomplished other than feeding the ego with empty words. It's amusing.

- Rob

Street Lethal

iTrader: (16)

Dig, you know that YSI your working on is night and day compared to this T-Trim. That's why I used the analogy earlier of installing an F3 Procharger on an L98, that is the only time I could see the need for running an open BOV at idle. Let's just see where this goes now. Joe was given information that allegedly makes sense to him, now lets see him apply it. I guarantee it goes nowhere, and the author who helped him will once again split town for a few years only to return with some new cut and paste with new members lol...

- Rob

anesthes

iTrader: (12)

Rob,

Have you ever built a supercharged car? What is your experience?

Here is some of the ones I've built since the 90s:












How many supercharged cars have you built ?

P.s, the Ysi is larger than the T-Trim, but not by a significant enough margin that it would make much difference at idle.

T-Trim: 55000 RPM 26 PS I1400 CFM 950 HP 75% 3.75" 2.75"
Ysi: 65000 RPM 30 PSI 1600 CFM 1200 HP 78% 4" 3"


If you still can't wrap your head around the fact that at idle the blower pushes more air than the engine needs, well that's your problem.

-- Joe

Street Lethal

iTrader: (16)

I am not arguing semantics with you anymore. It serves no purpose to knock you down a peg, which is what I did not intend on doing, but you keep pushing the issue. Okay. First, "It makes sense to you", the first thing you must clarify to yourself is who are "you"? What exactly makes sense to you, and why would your readers need to accept that as if you were some type of oracle who knows all, and can determine what works and what doesn't? If that is the case, then this thread should not even exist. However if it does somehow make sense, then fix the issue, case closed. I understand moderation might have you thinking you are someone you are not, but this has been going on for a very long time now with you. You have alleged, rather implied that you know more that Bob Rauscher (RBob to those who don't know him) in the past, when it comes to tuning, or at the very least, when it comes to his EBL system when over 500 users on here say otherwise, including myself. You also alleged, rather implied, that you know more about boosting an engine than I do, or the how's and why's, which of course everyone is entitled to their opinion, but then again I am not the one on here asking for help. I work with plenty of people who are like that. If I had a dollar for every co-worker who stated "having trouble opening this IRA, Annuity or Mutual Fund, what goes where or what year, or tax related issues", only to help them with everything only to then immediately hear "Oh I was going to do that", or "I knew that already, didn't have my coffee yet", blah blah blah, it's ego oriented, and this thread is clearly no exception when it comes to that very thing. I will monitor this thread occasionally to see if the problem gets resolved, and if it does, I don't expect the truth to come out as to what was the real issue. These threads normally end with a simple "I fixed it", or they are just left in limbo with everyone assuming it was fixed. Additional incentive for you would be to know that I just purchased a sixth gen Camaro with cold cash, and am now looking at a new Blazer, so I have no problem "sending" my GTA running a lot less than you powered by an alleged inferior system to yours, so name the time and place, and we'll do this and show everyone here.... who knows what. Sound good? Like I said, the time for semantics is over. No pics, no videos, no crying, so put up or simply shut up. There's your call out. I'll be waiting.

- Rob

[/done]

86CamaroDan

Street, you still got it in your head that blowers build boost at idle and they dont. Valve needs to be open at idle and cruise. Centrifugal blowers build boost under WOT and WOT only. They need a open bypass valve the rest of the time. Vortech and Procharger both say its needed on all of their applications over 5psi - Tial Q is direct competitor for big red race valve. As for who your calling out, I've never been to a track and dont claim to have the fastest car, but mines a daily that I drive everywhere - Not to prove my ***** fast, but for my own satisfaction. I have a better understanding than most because I have a education in automotive, and first hand experience working in the trade for the last 13 years, and I've built a couple of cars, so if your implying that I'm the one thats copying and pasting ****,I speak from first hand experience. Maybe you should stick to running turbos with no oil feeds on them.

anesthes

iTrader: (12)

Rob, without ranting about nonsense, could you please answer the technical question with a technical response. Why do you feel on a supercharger that the bypass/bov should be vented to the intake side? You've yet to do that.

I don't do this for a living, and I could care less what the readers think. I do this for fun.

It exists because I was curious if others have experienced this with the Greddy type S BOV, as explained several times.


I've asked JT several times to add others to Moderation staff, including people whom I often am in disagreement with, and he's said NO to each of them.

NO, I said I knew more about that stuff than you, which was evident in prior threads. I have a lot of respect for Rob, he knows the old factory stuff, and he's great at electronics. I don't like the EBL and have no use for it, but I've recommended it several times to folks who would have a use for it (search my past posts for evidence).

I've stated my credentials and experience, and board history is a ledger of my successes and failures. I know you've been building a 9 second 305 GTA for a few years now, but other than that project could you cite your previous boosted buidls? I've asked you if you have built or had experience with supercharged cars, and you've avoided answering that question.

I'll be the first to admit I don't have a lot of experience with Turbos other than the two setups I built for my own car. I've learned that they lag,that there is a lot of trial and error to sizing them, and they heat up everything around them.

In closing, I believe I stated last week I ordered a new BOV that a forum member has used (Dan) and had good luck with. If I didn't do that, I'd go back to using stock DSM valves (that you will see in the pictures I posted from the past 20 years or so of builds). My expectation that the known good valve, correct spring, and large enough vent (50mm) will solve the problems I had. If not, we will re-evaluate.


I think he was actually referring to Kingtalon, not you.

Rob's a decent guy, but he's got a hot Italian temper when people don't agree with him. I'm sure he'll be fine in a few days.

-- Joe

86CamaroDan

Well if thats the case I apologize, I know all about the hot italian temper.

Kingtal0n

Hes just butt hurt

I wasn't going to say anything but now you are just attacking everybody else to make yourself feel better.
The truth is, around half of your posts are complete nonsense. They make you look really dumb on the internet in car world.


I've never copy pasted anything unless it has 'quotes' around it. To do PhD research and get into a doctorate program I assume they check all my work for plagiarism, including online materials, so I've never once even accidentally copy and pasted info direct with no quotes. I think you are merely jealous of the level you will never attain in the brain, and its probably because you resort to personal attacks instead of research and learning when confused.

I've tuned around 100 turbo cars, most recent a couple weeks ago an S15 silvia. I get word of mouth business from previous cars.
The reason my project has no going to the track is because the entire budget to build a reliable daily driver V8 turbo Nissan was less than 15k, and it had to be done in under 6 months by me alone with no air, no lift.
Pretty sure I set the record on that one.
The point was to drive the car every day; it doesn't matter how much power it has as a daily. 300 400 500 its all the same to me when it rips the tires apart regardless.
You want to see a 500rwhp dyno pass and 10 second 1/4 mile, send me $224 for a cam upgrade, $200 for tires, and $200 for fuel and track fee. Theres nothing wrong with my car or tuning, it is purely budget limited.

Kingtal0n

Time for a break down

"Joe, do this thing that somebody else did, and then had problems with. Yeah he was having problems for some reason.
But either way, Do it because it 'works like a charm'"

-Bad advice
-do this thing that doesn't seem to work that I saw on the internet

Yeah, lets add more moving parts unnecessarily to an already complex automotive system because I saw some guy do it on the internet.

Next,
Here we see conflicting information with no scientific or mathematical reasoning.

First he "can't see a supercharger forcing that much cfm at idle" when clearly anybody with a calculator and basic knowledge can definitely 'see' that superchargers move enough air at idle to require a bypass. Even the Vortec website clearly states to use one.

Then goes on to say that "A bypass is to... keep pressure off the supercharged during idle" Suddenly out of no where after saying he can't see why it would need a bypass, now suddenly 'a bypass might be required'? Confusing and conflicting info,

Then finally some long paragraph reasoning with himself about why a bypass wouldn't be needed in this case, because just by looking at the engine and supercharger he can 'tell' it doesn't need one (without consulting the manufacturer or doing any math, just assumes and presents the info)

poor reasoning and lack of attention to details.

Next, lack of experience and knowledge,
-I can clearly hear surge at idle in the video, so lack of experience and knowledge to understand what surge is/sounds like.
Next he suggested a difference between bypass/blow off,
-bypass is a blow off, both do the same thing, it wouldn't make a difference here in this configuration (lack of experience/knowledge) x2
-Anesthes already told everyone what hes done and doing with the bov (lack of reading other people's posts and making assumptions)


Next, confusion and lack of knowledge,


-A centrifugal "wheel" has a similar impeller function as a turbo and can be plotted onto a compressor map, but that is about where similarities end. (lack of knowledge)
-A roots blower will NEVER need a bypass because it derives airflow from post-throttle valve (lack of knowledge)
He then claims "a centrifugal is not making any boost pressure at idle" which is a misnomer and incorrectly stated.
A true statement is "a centrifugal blower attempts to make boost at idle always by design, but because the engine flow rate is to the left of the surge condition at that pressure ratio for the blower, the unit will surge instead" (lack of knowledge/confusion)
And now finally hes back to "you need a bypass valve" after previously suggesting that the bypass be removed. Well, which is it? (confusion)


Next, Insensible response, poor knowledge

-air leaks out past impellers with poor construction and leaky seals, which likely got there because of poor blower maintenance or manufacture. It is not a desirable or intended consequence of owning a blower, and one should never depend on poor air seals to protect their unit (bad advice)
-again roots blowers don't have these issue, not sure why he brings in this as some kind of example (lack of knowledge)
-His quote of "centrifugal isn't linear" is complete nonsense to anybody that knows a blower is connected to an engine via belt, which totally makes it a linear configuration. (lack of attention to details) i.e. the blower impeller does not "flow more or less" as RPMS rise of either the blower OR engine. The engine is the non-linear unit in this example (lack of knowledge)
-finally if the engine breathing airflow in CFM was 'cancelled out' by the blower breathing airflow in CFM, then there would never be any boost as rpms rise. The blower literally has to out-blow the engine's flow rate at ALL rpms, or NONE of them. (because of the belt)

Kingtal0n

Jesus it just keeps going,
-Some BS about recirculation vs vented BOV, complete nonsense either way as bypass/bov is essentially identical for Blower-belt setups (lack of knowledge, misdirection of details intended for turbo applications)
-Excess CFM at idle, Excess CFM during Decel, Excess CFM during boost, there is ALWAYS EXCESS CFM why doesn't he get it yet? (lack of knowledge)
-State of conflicting ideas "needs a bypass but not sure what a bypass or surge really is"


When will it end?
Good information from Anesthes:
Of course he has to disagree.
-Blowers don't like recirculation bypass because it just re-heats them. No maf? No recirculate. (poor knowledge/advice)
-recirculation is for turbo impellers (my quote)
lol this next one cracks me up
-boost cannot be "controlled" by a bypass valve because any air leaking from the intake tract of a system will create unwanted impeller RPM which will unnecessarily heat the air (raise IAT), reduce blower efficiency, and causes the impeller to move right off it's compressor map into "out of breath land" where no more power can be made. It can damage the engine and blower. (lack of knowledge)
-Boost leaks are NEVER tolerable (a leaking bypass is a boost leak).
-compressor can't 'freewheel' in a belt driven application (what is this guy thinking?)
-No Heat at idle from impeller? LOL This is just hilarious. Its like hes never owned a blower or turbo before.
If you try resting your hand on a blower or turbo of a fully warmed car at idle. You will feel the heat. (lack of... experience)
There is heat from friction of the belt. heat from exhaust if there is a turbine. Heat from underhood heating of exhaust components etc... And heat from the boost situations moments before. Not everybody starts their car cold, then shuts it off cold without driving it. Is that what you've been doing? LOL
-squared nonsense "like a turbo". How many things are wrong with this statement?
1. No mention of what is being 'squared'
2. No math derived to help readers understand what he is talking about
3. Increasing rpm gives more boost pressure because the blower spins faster... It has nothing to do with anything being 'squared'
The ratio of engine to blower is named something like "drive ratio" and it specifically shows how much flow is available at every blower RPM.
The bost pressure resulting from this is completely dependant on engine flow rate. It has nothing to do with anything being 'squared'. The boost could sink to zero if the engine is too large, or it could go to 50psi if the engine is too small.
-if you are going to say something is 'squared' you need to provide math formula so others can follow your **** (lack of consideration for other readers / lack of words to explain phenomena)

sigh
Oh this one is GREAT.
-I hear the compressor chopping air at idle (NORMAL) (lack of knowledge)
I am curious what the manufacturer would say about this. Somebody should email Vortec/procharger and ask.

Will it ever end?

-Still thinking atmospheric venting is BAD (lack of understanding)
-Still thinks compressor surge at idle is "normal" (Its just a horse sneeze LOL)
-opinion to lock the bypass shut at idle (lack of knowledge)


Next, poor information, confusion?
-Thinks a supercharger is turbocharger and that a recirculated bypass will affect the belt driven compressor wheel.
Every turbo car on the planet uses a bypass valve in today's world

https://turbobuick.com/threads/why-n...1/post-2959148

next,
-he doesn't realize the lack of bypass will force the flow rate of the impeller to the left of the surge line. (lack of basic mechanical engineering)


Okay I'm done for now. Try answering all of anesthes questions first before backpedaling through all this garbage.
Its just post after post of "I never went to college for mechanical engineering and I learned everything I know from forums and cold starting my car in the garage"

Street Lethal

iTrader: (16)

... lol, the flea market of turbo builds claims no cut and paste. Must have struck a nerve considering how much your responding, so who is the one who is butt hurt here lol. Come on Talon, lets see one of them "pics" you so love to post of cheap parts in a non third gen, and then maybe a street video of you running one pound of boost claiming how wonderful of a tuner you think you are, and how great LSX engines can be, while posting in a third gen forum because nobody else on the web takes you seriously. Like I said, help Joe fix his issue, because apparently it is very eluding for some years and year now. Then maybe give him a few pointers with his MS tune, as lots of his fans are waiting for that infamous trip down the track, but first get those rules in check, don't wanna run the car without those rules being adhered to, as heaven forbid the car see's an eleven second time slip with no cage, they will take it away and throw away the key. Surprised MS has no street logging that could give us the 1/8 time so we can calculate the 1/4, but I digress, that'd be too easy. Let's just keep pointing fingers towards the rules. But that's five years from now in terms of cage, adequate for people to just forget. Maybe then the BOV issue will be resolved by then too. But all this in jest of course, I am having a good time here. Fix the issue giuys, I'm sure plenty of people are reading this and they want to see it resolved. Good job representing Joe, as always. Explains a lot regarding some of the personal things you shared with me, believe me.

- Rob

Street Lethal

iTrader: (16)

Speaking of which, and not to mention, considering how long it took you to respond to certain topics, hours after you had read them, it was almost as if you had an "epiphany" and suddenly had the need/urge to write lmao, Those hours must have given you ample and sufficient time to frantically search the web trying to generate a response, for the ole cut and paste trick lol. Anyone with half of a brain could have figured that one out, but then again....................

- Rob

Kingtal0n

does anybody know what he is saying now? Did I break him?

I see the so I assume hes troll? needs timeout? got his face rubbed in own poo and now broken sorry

anesthes

iTrader: (12)

Street Lethal

iTrader: (16)

Meh, don't take my word for it Joe, keep listening to some of the others about how to run your BOV, they will get you where you need to go, and fast. Sadly, it won't be a good place. Joking aside, I told you that I agreed with Diggler posts and posts ago after realizing what it was you were complaining about, that being you needed a bypass valve and not a vented to atmosphere BOV. Basing your information on FB posts like the one you quoted above through an image copy is a waste of time, so why not go to the source. Listen to Vortech about what to do to avoid compressor surge... since they did all the testing in house, as well as built the unit themselves; Go to the source.

Here is their number: (805) 247 0226

They also have a contact page if you don't want to call: https://vortechsuperchargers.com/pages/contact

They also have a FAQ page about compressor surge, see below;

... so in the end, I hope you realize that I am trying to help you Joe. I have no time for pissing contests, which is what this website has become. Even from guys who don't even own a third gen.

- Rob

When should a race air bypass valve be used?

Any supercharger system that is operating in excess of 10 PSIG requires installation of a race air bypass valve to prevent compressor surge. All V-1 R, V-1 T, V-7, V-3, and V-4 superchargers require a mondo air bypass valve.

When should a standard air bypass valve be used?

A standard air bypass valve should be used on all supercharged applications where the supercharger is making more than 6PSIG. The advantages of using an air bypass valve includes eliminating compressor surge (the noise heard during deceleration) for quieter supercharger operation, and reduced heat soak in the discharge tube and the supercharger.

https://vortechsuperchargers.com/pages/faq

anesthes

iTrader: (12)

Rob,

Here is the Vortech race valve. Where do you think it vents to?

Kingtal0n

Wait hold on don't spoil the surprise lol

hahahaha im waiting to get an email back from vortec just relax
hopefully their tech isnt lame

For now, tidbit
https://ls1tech.com/forums/forced-in...ml#post3575937

I hear that you get up to a 40 foot drop in cruise speed temperatures rofl

anesthes

iTrader: (12)

I did a 15 foot drop off a roof once and it wasn't pretty. 40 would be killer!

Street Lethal

iTrader: (16)

Completely missing the point Joe. Stop listening to the soy boy above, and just call Vortech directly. Tell them your scenario, and what they would recommend. Post what they say. Here is a spoiler, I already did. Don't tell me you can't afford the call, I mean after all we keep hearing about investment after investment, so what is a simple ten bucks in a phone call. The very fact that you continue on with this charade while avoiding a simple call to Vortech directly almost underlines you are not to be taken seriously, nor this thread. Why do you think others stopped bothering with you in here, other than the one guy who more than likely is not attracted to women, nor they to him lol...

- Rob

anesthes

iTrader: (12)

Rob,

Here is the manual from Vortech. Notice it says the exact thing I've been saying for two weeks now:





Please note #2.

I've been using Vortech superchargers for 20 years, and I've always vented to atmosphere, just like they recommend using their race BOV in the above documentation.

Why did Vortech charge you ten bucks to talk to them? They never charge me. I just give them my serial number.


-- Joe