crazyjim

I was thinking of just running Water or Alky injection instead of running an intercooler as to limitations of space. I don't want to chop my car What are the pro's and cons?

Steven89Iroc

There are a lot of people who only use one or the other, they both really help resist detonation. You should have no problem using W/A injection instead of an IC. Of course there are different kinds of intercooling (air/air, water/air) as well as different kinds of injection (water, isopropyl, ethanol, methanol, single stage, variable adjust) so it's (as usual) not a simple answer as to which is better.
It would also depend on setup-specific variables.

Intercooling (in general)
pros- no need to refill (it's there all the time), dissipates heat into ambient air (instead of into the engine), ice can be used with water/air, it can look cool(?)
cons- requires more space, can get heat soaked and become less effective, pressure takes longer to see engine because it has more piping to fill, added complexity with water/air, extra weight.

Injection (in general)
pros- has less weight, saves space, cleans out your intake mani and combustion chamber, works the same no matter how long it's used (no heat soak), doesn't require miles of extra piping to fill
cons- requires refilling with various liquid, requires more small parts (than an air/air IC), uses a minor electrical load, dissipated heat has nowhere to go but into the engine still.

I personally like the idea of both at the same time. I'm going to install a WI setup on my Talon when I get back to the other side of the country, and if my Camaro doesn't like 15 psi on 93 octane with the huge air/air IC, I'll eventually put WI on that too.

Sonix

iTrader: (1)

hmm, never even thought of that one, but I guess it makes sense, you are not making heat "disappear", as far as "sum of energies in = sum of energies out", you still only have one output so....

just moving it from one molecule to the other... Yet still it works though... hmm

Steven89Iroc

Yeah, that's my line of thinking, but I could be off for some reason I suppose.

The way I think of it is that the injection makes the charge that's there more efficient somehow, while the IC does more of increasing the amount of that charge (by increasing air density), but also makes it able to be a little more efficient (by reducing detonation).

This line of thinking would make sense with what I experienced when I ran E85 (85% ethanol, 15% gasoline) in the Talon. Even though it didn't register more airflow through the MAF at high boost levels (24 psi), it made a WHOLE LOT more power than 93 octane (24 psi) in cold weather had previously. This was with no knock retard in any situation, btw. I found that to be strange.

crazyjim

Ok, those are pretty good pro's and cons actually.

I don't want a bunch of IC piping under my hood for one, and I don't want to hack the front of the car to get an IC functional under there. I figured strait alky injection or methanol injection would work fine. From what I read it actually cools better than a water sprayed IC and cleans your motor at the same time

Another con is this: Failsafes, they're complex and not truly failsafe. If the alcohol injectors plug up, lines break, etc and you don't know about it while you're in big boost... you're done for =\ That's the one thing that scares me. I'm trying to think of a way to use some sort of pressure switch that senses pressure drop and will retard timing. But I don't want it to do so everytime I let off the gas

Thanks for your replies! It's helped a lot. On AVERAGE does anybody know how long a gallon tank of alky will last? If you're boosting all over the place lol. BTW I'm going for around 600bhp (hp @ the wheels) on weak california 91 octane on a small block 355 or 383. I know that's probably going to be around 15psi. I'll need SOME sort of cooler to run that psi.

Willie

iTrader: (1)

....I don't want a bunch of IC piping under my hood for one, and I don't want to hack the front of the car to get an IC functional under there.

Most of my IC piping is under the car. As you can see, my engine compartment isn't cluttered with piping. At least in my opinion it isn't. I didn't hack the front of the car either. I use ATI's twin IC system both located horizontally at the front corners.


I figured strait alky injection or methanol injection would work fine.

Sure it will. I used only this for years without ICs with good success.


From what I read it actually cools better than a water sprayed IC....

A properly tuned injection system is more efficient that an IC system. I've seen air temps BELOW ambient with water/alky. This is impossible with an air-to-air IC system. Where the IC system is more beneficial is when not at WOT when the water/alky is injecting.


Another con is this: Failsafes, they're complex and not truly failsafe. If the alcohol injectors plug up, lines break, etc and you don't know about it while you're in big boost... you're done for =\ That's the one thing that scares me.

Although not installed on my new turbo setup, I plan on using this:

Display Products

which will retard my timing ten degrees if water is not flowing when it should be.


On AVERAGE does anybody know how long a gallon tank of alky will last?

Tough question to answer with so many variables. In general, I use about one quart for four 1/4-mile passes. I hardly get on it on my daily driving to activate the water as it tends to leave chunks of rubber on the streets.

Ol'Blue

iTrader: (1)

I am currently running 15psi, non intercooled with water/meth injection on my 305 without a single problem. The snow performance system was easy to install, doesnt take up a bunch of room (I use my washer fluid resevoir for the tank) and it actually lasts for a good while. The con that I will add....Tuning the alcohol injection system ex. what nozzle size, pump pressure, when to start injecting. Mine was way rich at first....i recommend a wideband dyno tune to get it working properly. Which I need to do

Elliott S.

Heat may just be transfered from one molecule to another, but the overall temperature of the alky plus air drops. For example, say you have a tub of hot water and a bucket of ice cold water. Throw the bucket into the tub and the overall temperature of the tub drops dramatically as the cold water sucks up the heat of the hot water.

Also, no one has mentioned here that alky/methanol is also a very good octane booster. Not only do you get the cooling effect, but octane is bumped up as well.

If youre interested in a kit, might want to check out: Devilsown Alcohol Injection - Methanol Injection - Water Injection They have very good prices

Willie

iTrader: (1)

I don't know if this is important to you but it is to me: The cooling effect of injecting, whether it be alcohol, water, meth, etc., is only at WOT. With ICs, the cooling effect is all the time. I use both but if I had to choose one, it would be ICs.

For injecting, my preferred source is:

Alcohol injection | Alcohol injection systems | DIY alcohol injection kits

Julio knows a ton about this stuff and he owns a thirdgen!!

Willie

86Z

iTrader: (4)

hey willie is that the same roc that you had the D1SC on? you swapped to turbo's? i'm running 10# with a D1SC on my 305 but i dont like having to tighten the belt so much, i need to work on fixing that, i'm also looking in to getting an alky kit

Steven89Iroc

More very good points brought up. I won't run alky by itself for some of the reasons listed, though it works great by itself for other reasons listed. However, it looks great as a second helper. I doubt most cars with properly set up intercoolers and water/alky would benefit much at all from running race gas, which allows one to get the most out of the setup just about always.

Willie

iTrader: (1)

hey willie is that the same roc that you had the D1SC on? you swapped to turbo's?

Yep, a pair of them but I haven't tuned it yet. Still have a long way to go. I did keep my twin IC setup although it needed "replumbing".


i'm running 10# with a D1SC on my 305 but i dont like having to tighten the belt so much, i need to work on fixing that, i'm also looking in to getting an alky kit

Well, the reason why I went the turbo route was because of the supercharger belt issues. And I broke a brand new 4340 crank snout under zero boost conditions. We suspect a defective crank forging because this happened with just under 1800 miles on a rebuilt engine -- again, it never saw boost. Upon teardown, we found no causes why this occurred.

I'm also keeping my water injection but added Julio's progressive controller and will be adding the Snow module (link above) as a safety blanket. I'll be switching to methanol too.

And one additional comment. Although I would choose intercooling if given only one option, the water/alky injection is MORE effective in reducing intake air temps. I posted results of my rather crude test a couple of years ago right here on this forum. Basically, water/alky reduced my air temps to BELOW ambient. Starting with an air temp around 135 on a 95 degree night, it dropped to 85 degrees within two seconds after injection started. Can you imagine running 85 degree air temps at 14-psig boost? I was. No intercooler system can come close to this.

Willie

ttypecamaro

iTrader: (2)

with water/meth injection and an intercooler would it be any more effective to inject the water before the intercooler while the air is hotter? Is an intercooler more efficient with a higher or lower temperature difference? or is it fairly constant?

argument against my idea:
I wasn't paying attention in heat transfer class. I was thinking that intercoolers work because of a temperature difference, so cooling the air before it enters the intercooler might reduce the intecoolers efficiency. So the partially cooled and wet air going through the intercooler would be at a lower temp, but harder to cool down because of the higher heat capacity of the liquid mixed with air and smaller driving force (temp difference).

for:
I also thought about the previous statement that the heat is not dissapearing, it still goes through the engine with water injection, but it would go through the intercooler first. The intercooler actually allows heat too be removed from the system. So if the intercooler is more efficient with a lower temperature difference, then this would be the better idea.

maybe it doesn't really matter where you inject the water? maybe I need to get a book?

another idea:
the water could do the majority of the cooling before the intercooler, then have a "dryer" setup that would let the liquid fall out of the intake pipes into a catch can. But is the air moving too fast for the liquid too fall out? or is most of the liquid evaporated by that time anyway?

TTA#299

Alky works best if it is on the up pipe near the TB .


http://us.a2.yahoofs.com/users/43def...wXY0EB7vktgHAk

Alcohol injection | Alcohol injection systems | DIY alcohol injection kits

Gunner823

iTrader: (2)

So if I rigged a small alky injection system to work with my P600B, and put the nozzle in the small opening on the charge pipe right before the TB, I could see some nice boosted power gains? The single IC is a pain in the *** because it blocks radiator airflow. I'm interested in moving it to the passenger side of the nose, but it sounds like I wouldn't have to bother because the cooling effect from alky would be great enough as to offset the effect of high engine temps on the intake charge. Am I understanding this right?

TTA#299

you tried the TTA style intercooler that is behind the radiator and has a scoop that draws air from under the car ?