PT

Hi,

I'm contemplating of installing a full bay intercooler on my car but have a few questions.

From my understanding, one will get more hp (assuming same boost & everything else) due to lower charge air temp.

But... a) a bigger intercooler will likely cause more lag because it will take a tad longer to fill - Is that true? b) I'm sure there's limit to benefit of lowering the charge air temp. Without knowing how efficient I'm at (i.e. don't want to spend the $$$ to install a temp sensor since I'm leaning on replacing it), is there any other way I can make a more sound judgement?

thanks...

BTW - the car is used primarily on the track. It has SC cam, GHL header, K27HF and a Garretson intercooler right now. And I'm running with a .6 bar spring, though seeing .9 bar on track.

jhunt@huntinter

you probably have a .8 bar spring (stock).

The big answer is ... it depends

If you live in a cool climate you probably wont see much benefit. Before investing in it I would install an IC temp gauge. See if you need it in the first place.

IC temp gauge (Davtron) model 308FD $160 (make sure you get 2' or 3' more wire. standard isn't quite long enough) www.davtron.com

Brent 930

It might cause more lag but if it's designed right it might not.

Well, the limit to cooling the intake air is having a 100% efficiency IC on boost. That isn't real world conditions but you can do better than the Kokeln with a well designed full bay. Your garretson IC is probably just a little less efficient than the Kokeln. The Kokeln IC is between 45-80% efficient I figure and depends what kind of driving and what the outside temps are. The main problem is the IC is over the engine and inside the car. Most other cars with front mount engines have them outside and away from the engine but we can't do that.

I also run a .6bar spring since I will outflow the header dump pipe to the wastegate. When warm on the track I will see 10-11psi, closer to .9bar when cold out.

Brent 930

By the way a full bay IC will cost too much unless you can do it yourself.

Sameer

The Kokeln Intercooler is the finest, most efficient intercooler on the market BAR NONE! Kokeln Intercoolers produce lower intake temperatures and higher flow than any other intercooler due to a larger cooling mass, superior design and greater efficiency while retaining the factory air-conditioning! Comparison of the Kokeln Intercooler to other products on the market revealed the following:

Test Result

Charged side face area in square inches Cubic inch mass
Stock 21.4 258
Andial (Garretson) 72.6 508
Ruf 53.5 498
Kokeln 73.0 642

For comparison purposes a test was ran on a stock 1988 911 turbo at 5000 rpm with an outside ambient air temperature of 85 degrees Fahrenheit and turbo flow rate was approximately 430 cfm. The results were as follows:

Intake Temp Outlet Temp Pressure Drop
Stock 218 151 .50
Andial 220 120 .50
Ruf 220 119 .50
Kokeln 222 109 .48

Fits in the stock location, with Air conditioning, can flow as much as 900 CFM @ 2.6/1 pr Ratio with less than 1 psi drop

For all '78-'89 930's
Turbocharger and Intercooler technology have improved dramatically in the past few years. The Kokeln Intercooler uses the latest technology in every aspect from the core material to the bypass valve assembly. The bypass valve included in he installation kit replaces the old cast aluminum valve (7 Pounds) with the latest bypass technology. This valve (less then 1 pound) bypasses more air faster than stock and provides boost approximately 1000 rpm sooner.

Kit includes: Intercooler, bypass valve, bypass sleeve, rubber elbow and all mounting hardware and fittings.