The intake and outlet on my intercooler has an inside diameter of 2 1/4 inches. GT35 outlet is only 2". the rest of the intake ducting is 2 3/4 inches with a 70 mm throttle body. This is on a built H22 running 22psi. and 500+ whp. Would there be any advantage to having 2 3/4 inlet/outlet on the intercooler. How much difference? Even though the system is pressurized it seems it would restrict flow. Any velocity issues? This is an E85 street driver.

The shop where I bought it (they're doing the work) says it doesn't really matter since they're bigger than the turbo outlet and it's a pressurized system, unlike NA.
Anyone ever try different intercoolers with different openings and other things remaining the same?

 

Here's how my math comes out for 500hp @ 22psi:

Intake dimensions:
Cold side piping = 129.86 mm - Before the supercharger or turbocharger
Hot side piping = 83.02 mm - After the supercharger or turbocharger
Throttle Bodies = 1 x 83.02 mm

Intercooler dimensions:
Intercooler minimum inlet area = 27.0 square inches (this is the surface the air sees coming into the intercooler so your depth X your height)
Intercooler minimum volume = 843.0 cubic inches (depth * height * width)

If my math is right, that's the sizing that will give you less than 1hp loss in your intake path... anything smaller will work, but you'll be trading off top end for lag / throttle response / pressure response ...

http://www.superchargerperformance.c...alculator-v2-3

 

Don't know of many intercooler inlets that are that large. If the GT35 turbo outlet ID is 2" would I lose much having 2 1/4" intercooler inlet/outlet over having it be 2 3/4" from the turbo to the throttle body (70mm TB).

 

Intercooler has been pulled. I will get one with larger I/O if it will make a difference.

 

Ordered intercooler with larger I/O. Waste of money?

 

dyno it and let us know.

 

a better core would have more of an effect at those size i/o then new inlets or outlets