moneyman380

Well like the title says here's my install. Hopefully it will help some other members in their install. First of all I'd like to say that so far Im happy with the quality of the headers. I've seen a lot of people on here talk them down but especially for the money I don't think you can beat them. Yes the collectors are 2.5" but you can always cut them back and obtain a 3" collector. I also had heard some of the older versions having header flange alignment issues with the bolt holes not lining up with the heads. But they must of fixed the issue at the plant since because mine fit without any issues.

no new tires

pics

TennesseeIroc-Z

iTrader: (7)

Been looking at these- also curious in the "shorty" header/y pipe they offer, if it can be had without the smog tubes.
Also, anyone installed their cat backs? Looks good, but curious as to real world experiences.

90camaro355rs

pics of these please

moneyman380

Sorry guess prob should of said last night . My pics won't upload because they are too large in size for thirdgen. Have to downgrade the pics first on my phone . I have plenty to upload and will get them up ASAP.

moneyman380

Here's the headers out of the box

moneyman380

A pic of the passenger side header. Cleared everything but the starter solenoid even with my mini starter I had to dimple one of the tubes.

moneyman380

Trans cooler lines are close but I plan on heat wrapping them.

no new tires

The first [FAIL] right their...they shouldn't be any where near their.

moneyman380

I would like to thank Scottyrock for helping with my install. For the passenger side header install you will need to remove the starter, all spark plugs, your heater fan box. Hopefully you don't have your a/c on cause your going to have to remove alot of your system to get the clearance needed. The car needs to be lifted off the ground at least 18-24" because the only way to get it in is through the topside. You need alot of room on the bottom side to drop the header in then clock it into position on the head. You can start the header flange bolts but don't tighten them because you need to get the starter bolted up and connected first. I was told you can reuse a stock gm starter but I didn't even try. Someone had mentioned using a gm mini starter from a v6 or LT1 would clear the header just fine. I purchased a new mini torque starter simply to upgrade and hopefully save me some frustration down the road. I believe no matter what kind of starter you decide to use its going to be a nightmare to replace. I'm talking about having to disconnect the entire exhaust system and taking the header loose just to remove the starter. So my advice, don't put a used starter in when installing these headers.

moneyman380

As for the driver side header it needs to be installed from the bottom side. Again you need the car up around 18-24" to get the clearance you need. But first you need to remove all plugs, temp sensor, oil pressure sensor, oil cooler if you have one, oil filter, and you need to disconnect the steering shaft. The only modification I had to do was a little grinding on the LCA mount as you can see in the center of the pic.

moneyman380

Here's a pic of the driver side.

moneyman380

If I have time to today I'm going to cut a notch in the transmission support bracket to clear the collector pipes. One is not touching but I'd like to have a little more clearance for motor vibration.

moneyman380

Ok I bought the shortest Plugs I could find, Accel header plugs. All are good except this one plug. I can get this threaded in unlike the ngk plugs I had already had but it's super close to the header. It's too close for a boot and I'm wondering if I have another option other than putting a dent in the header tube. I'd hate to modify them especially restrict flow.

no new tires

^You get what you pay for...

DynoDave43

iTrader: (11)

I wonder if a set of these would fit?

http://www.summitracing.com/parts/ACC-9001C/

moneyman380

Nothing to do with OBX. I believe it's my fault for not having angled plug heads.

ricksmorris80

Thats horrible i put flowtech on mine dropped in very easily only had to pull spark plugs.

moneyman380

I've run flow tech headers and they are complete ****. I would never buy anything from them again. I too only had to pull plugs to install them because they were shorty headers. All long tube headers require more work to install period.

ricksmorris80

I vant speak of the longevity, and yes they are shorties i didnt see the part about long tubes. What did you hate about them?

moneyman380

On my flowtec headers the ceramic coating didn't last long. The primary tubes were small and the collectors were small. Also the overall construction of them just seemed cheap. I wish I would of bought hooker first go around. But so far Im loving these OBX headers. So glad I upgraded.

moneyman380

Ok finally had some time to finish the exhaust. Had to notch the transmission support as you can see in the pic. I believe OBX set their system up on a stock engine with factory engine mounts. I think the only reason I had to modify my bracket is because I'm using poly motor mounts and a poly transmission mount which raises the engine and transmission just enough to where the exhaust hits the 700r4 rear support bracket.

steveo346

How much did ya pay for those obx LT's?

IrocRoadRacer

I paid $400 for them, but I am parting out a car and have a used set for $275 shipped.

Ron U.S.M.C.

So how much HP and Torque will you get with these added as opposed the shorty's ?

InfernalVortex

iTrader: (4)

Most comparisons I see show very little peak increase in torque or power from long tubes to shorties. Think of it more like the difference between TPI and a miniram. Long tubes are a tuned length (primary length) that will help the engine make more torque through the mid range. Shorties are so short that you will never get into a range where their wave tuning is helpful. They have to rely purely on their ability to flow to make power. The TPI sucks because it's tuned for low of an RPM range. Imagine if TPI was tuned for 3000-7000 RPM how well it would work. Long tubes help until you hit peak power, and then they are the same as shorties until shorties get into their wave tuning range, but that's too high for sbc's so you never really get there.

Essentially, LT's get you a little bit more power everywhere, even if the peak power increase is only 5hp or so over a same diameter shorty.

thebandit50187

you have that backwards. you wanna use shorties on cars that operate below 5,500, and on SBC's they flow much better than cast iron exhaust manifolds, and usually produce more peak torque than long tube headers. So shorties are better choice for a street motor. If you run a big cam and HIGH flowing heads then you really want long tubes. the exhaust pulses pulls the exhaust gas from the cylinder, providing optimized scavenging. shortie dont do that as well as long tubes do..

case in point, fast, high revving drag cars dont use shorty headers.

thebandit50187

wouldnt angled plug put it further toward the header?

thebandit50187

how do you like these headers? im thinking about get these for my "trans am" to replace the rusty heddman headers i have on it

InfernalVortex

iTrader: (4)

No, you're wrong.

Long tubes still make MORE power than shorties in the RPM ranges that smallblock chevys operate. For drag cars this is free extra power. That's why they use long tubes. Note this also helps cars with big cams to claw back some of the low-mid range torque and will broaden the power band.

Shorties are better for street cars for packaging and convenience reasons, not for wave tuning or performance reasons. If you could hit high enough RPMs you'd get the same benefits from shorties that we get from long tubes.


You can see in the dyno graphs here where the long tubes go into their optimum range and create a huge bump before you hit your peak torque numbers. Note this particular example is for equal length primary long tubes. For the average commercial long tube available each primary will not be hte exact same length, so you wont get quite as much of a defined bump. You trade a higher peak for a wider range, since each primary will be optimized for a slightly different RPM range. (Note this is also how dual plane intakes work. There is a wider range of port lengths which leads to each cylinder being optimized for a different RPM range. That means you trade a narrow peaky power band for a wider, broader power band.) This is where long tubes are advantageous, and this is also why the raw horsepower differences at peak hp are usually small. Peak hp differences are not where the biggest benefit of long tubes is. It's the mid range where the biggest benefit from long tubes happen, and if it werent for the impracticalities of them they are well suited for street cars. For a TPI car adding more torque may just lead to traction problems, however.

Note how at 6500 shorties actually surpass long tubes. This could be due to many reasons, but i suspect you're getting into a desctructive interference range of wave tuning with the long tubes and a constructive range of wave tuning (likely a harmonic of its primary range which is beyond what sbc's can accomplish) with the shorties.



http://www.sandersonheaders.com/Lets-Get-Technical.html

Another source (David Vizard, who I dont always agree with, but he's correct here)

http://www.popularhotrodding.com/tec...#ixzz3AT4v2Z9s


Another source if two isnt enough:

http://www.popularhotrodding.com/tec...nd_length.html

Back to your post:

Have you ever given any thought to why this is true? What is going on here? Wave tuning is pretty well understood and we have many formulas to determine and optimize it for given situations. Primary diameter and primary length both play a part, but the formulas use a bunch of greek letters and trigonometry that is probably a bit over your head so I will spare you details.

But you do admit that long tubes "scavenge" better. What is scavenging? It is wave tuning pulses bouncing back from the collector. The longer the primary, the longer this takes for each pulse to bounce back. The wave has to travel all the way down to the collector, and then bounce back up through the primary(s) with a negative wave to pull exhaust out of adjacent cylinders. Of course, the actual system length also has its own wave tuning, which is why a longer exhaust system is better suited for a street car, and a shorter system is better for drag cars.

For long tubes, this time for the waves to bounce from the collector back to the exhaust valve is longer, and it coincides with the mid range and you see advantages at and below peak torque generally. For short tubes, the same effect can and will happen, but we are going from a 20 inch primary length, to a ~5-10inch primary length. This drastically shifts where the scavenging is most effective. There is nothing mathematically different about shorties which means they do not scavenge, except for the fact that the primaries are too short to allow the wave tuning pulses in reasonable RPM ranges. They have to rely purely on airflow and primary size being balanced for flow and velocity for a given engine to create more power.

thebandit50187

you win

thebandit50187

i didnt mean disrespect and was trying to be helpful. i'd read what i said in a magazine a few years back. they had a chassis dyno shootout and concluded that the stock engine they tested on would benefit more from the shorties on the street because it was a street car and made more torque than the long tubes even though the long tubes made more horsepower. and my favorite Quote "We buy for horsepower but drive torque" true statement. ill agree TPI's do make almost too much torque but ive driven cars that made more peak horsepower and can barely brake the tires loose (wheres the fun in that)

dakota9576ia

iTrader: (1)

I run the OBX headers on my 91 Z28 with a 383 pro-comp straight plug heads. My clearance is the same on that same plug but I can get the boot on and slide the fabric style boot protector on and have no problems with frying the boots.
Just thought I would let you know.


Brian

rusty vango

and that IS and ALWAYS will be the problem with headers. there ALWAYS has been some dinging. removing and downright mangling of the car to use them. and you would think that they would be engineered to just FIT!!! imagine if piston companys tried this way of thinking. "some massaging" MAY be required!! its the "ah, that's close enough." mentality that makes headers not worth a damn on a street driven car.

thebandit50187

i agree. the only car I put headers on that wasnt a huge pain in the *** but still sucked was a 86 buick regal (GM G-body). i did have to buy a floor mounted shifter because it was of course a column shifted automatic and i had to buy a dual exhaust crossmember for the transmission

InfernalVortex

iTrader: (4)

This makes my Hedmans sound like a piece of cake. They required some cutting but nothing nearly this horrible.