hey guys just doing some reading and finding out that my IC pipe kit inner diameter might not b a full 2.5" might b more like a 2.25 well anyways i plan on upgrading my turbo and shooting for 450-500HP will this size difference make a difference at all? would it b wise for me to upgrade to a full 2.5" pipe kit? thanks


evoisdream

 

S.C.C. ran a series of articles "Suck, Squish, Bang, Blow" which describes in great detail, the components of a complete turbo system and covered piping diameters;
"For setups under 300hp, the piping diameter should be kept to between 2 and 2.25 inches in diameter. For up to 400hp, 2.25 inches from the compressor discharge to the intercooler with 2.5 from the intercooler to the throttle body works well. For 500hp and up, 2.5 inches works pretty well."
S.C.C.
October 2001
page 304

 

Hrmmm so maybe i would only need to go with the new side...... i wonder if it would b a Noticeable difference like 30HP or something big.... if it was like 5 woudnt even worry about it

 

Hrmmmm

 

I wouldn't worry about it. The Helix should be fine. Have you measured it?

 

On the Evo, the lower IC pipe is restrictive and you can get 5 or so HP with a better one like AMS, but you mostly gain spool up. The UICP will LOSE you HP if you are not pushing more than 25 psi or have a bigger turbo. Same principle as a bigger intercooler but none of the cooling properties. Just more space to fill. Both ICP's will help with more consistent boost though since there will be less rubber tubing to expand.

 

This shouldn't really matter much.

No matter how much boost you put through it, the volume of the engine remains a relatively small 2.0L. In other words, increasing the boost pressure does not increase the volume of air moving through the IC pipes - which stays relatively constant. This same principle applies to the TB and any component on the pressurized side of the turbo.

 

thanks for the help guys now less bends would make signifigantly more power or just slightly better spool etc.... like if i went from the helix top pipe to like the buschur one.... thanks again

 

Fewer bends is always better, but the value of "better" is directly proportional to the velocity of the air charge moving through the pipes.

 

for the minimal requrement i would think.

and it's back in october 2001.

i think 3" would be more than enough for anything under 400whp.

would go 3.5" for 500whp under with 4" exhaust.

just makes more sense on boosted car to have a bigger travel with shorter pipe.

with those numbers, you would need a bigger pipe for the bigger turbo anyway,.

stock's 2.5" all the way, exhaust, intake, ic pipes.

 

any more substantial info from our vendors or anyone?

 

Thanks for the info.

 

so the buschur 2.5 inch lower intercooler pipe should be fine for a stock turbo setup? Or will I get lag? I do have a tune for it.

 

bump

 

no tune needed, less lag , quicker spool