intercooler ???

[tb8125]

I have a second gen trans am 79 that I am going to supercharge.... I am running in to trouble with intercooler location... My question is how important is it to have air flow across the the intercooler..... I have place to put it but fresh air flow will be very low... any suggestion would help thanks...

[DeltaT]

It's highly important not only to get good air to the IC but also to allow the heated air to escape after flowing through the IC. To use an extreme case as an example, if you completely blocked the rear of an A2A IC with a piece of cardboard, even if you had plenty of air available at the front of the IC you would effectively have a large heatsink. It would lower your charge air temps but only very briefly as it came up to temperature.

An option is horizontal IC placement with a properly shaped duct gathering air. A number of guys at ls1tech.com are running this option, if you search in the Forced Induction section.

If you have no space for an Air2Air IC, then consider plumbing for an Air to Water. You could put it in the trunk if you needed to. Corky Bell's book 'Supercharged!' has an excellent section on intercoolers as well as being a great overall supercharging resource.

Jim

[wicked68]

what boost pressure do you plan on running? you may not need an intercooler
I run max 10.5 on my f1r in road racing and I dont run an intercooler. it works fine. my car runs cooler since i removed the intercooler and opened up the airflow to the radiator

[RSX302]

I agree you don't always need an intercooler. It all depends on application-- compression, fuel octane, timing and boost level, etc.

Since I'm running low compression and boost on my LQ9. (8.5:1 @10psi) I'm not going to initially set-up an intercooler. I really don't think it will be needed. Less plumbing, weight, etc. We’ll see how it runs.

Intercooler vs Non-Intercooler

1 psig boost = 1.5 deg timing = 1.5 fuel octane

If memory serves, adding an intercooler to an existing non-intercooled engine is worth 2 psig boost or 3 deg timing on the same oct.

At the same token, by adding 3 octane points to a non-intercooled engine is worth 2 psig boost or 3 deg timing.

It’s all about controlling detonation (knock, pre-ignition).With the higher compression engines such as the LS vettes, it requires intercoolers to stay on the 91oct fuel to prevent detonation.

So if I can run max hp timing on 10psi boost and 91oct without an intercooler, than adding an intercooler will not add any benefit. At least from what I’m reading, a colder intercooler does not provide more hp, but a hot intercooler on engines relying on its cooler temps to prevent detonation will suffer. Hence CO2 or NOS spray to the intercooler.

From KenneBell;
Iced Intercooler Water – This is one variable you need not be concerned with. Cooler intercooler water does not increase HP.

[DeltaT]

Cooler air charge is more dense and will support more HP. The key is to have a properly sized IC placed so that it gets good air to and from it. In your example "So if I can run max hp timing on 10psi boost and 91oct without an intercooler, than adding an intercooler will not add any benefit.", the right IC should net you about 10-15% more power with almost no loss in boost pressure.

For the same reason, this makes no sense:

"From KenneBell;
Iced Intercooler Water – This is one variable you need not be concerned with. Cooler intercooler water does not increase HP. "

The main benefit of a W2A IC is the ability to run ice or another coolant to achieve sub-ambient charge air, increasing HP and providing further insurance against the dreaded detonation.

A prudent FI setup (especially street-driven) always designs in an intercooler unless you absolutely cannot fit one. Then meth/water injection would be the next best thing. An IC is the cake, water/meth is the frosting.

Jim

[RSX302]

Cooler air charge is more dense and will support more HP. The key is to have a properly sized IC placed so that it gets good air to and from it. In your example "So if I can run max hp timing on 10psi boost and 91oct without an intercooler, than adding an intercooler will not add any benefit.", the right IC should net you about 10-15% more power with almost no loss in boost pressure.

For the same reason, this makes no sense:

"From KenneBell;
Iced Intercooler Water – This is one variable you need not be concerned with. Cooler intercooler water does not increase HP. "

The main benefit of a W2A IC is the ability to run ice or another coolant to achieve sub-ambient charge air, increasing HP and providing further insurance against the dreaded detonation.

A prudent FI setup (especially street-driven) always designs in an intercooler unless you absolutely cannot fit one. Then meth/water injection would be the next best thing. An IC is the cake, water/meth is the frosting.

Jim

Cost effectiveness and effort is the downside to installing an intercooler system. If 5-6psi boost is all that is being used, it’s hard to justify the little gain in performance. As boost levels increase, the payback gets increasingly substantial.

I think in Kenne Bell's case, the belt on the supercharger is the difference. If you cool the air and make it more dense, you will need to add more volume (pulley change) to take advantage of it. If you don’t, no advantage will be gained because you have the same amount of air being pumped—or at least that’s how I'm reading it? In the turbo set-up, it has the ability to maintain constant boost to make up the volume from the denser air generating more horsepower. 10-15% like you stated. Which is why you convinced me to install one. There is a very good possibility that I will run higher boost in the future.

Thanks Jim for the reality check and slap to make me install an intercooler. I know I will be glad I did later.