Project_EK

iTrader: (1)

Will having 2.5 IC piping restrict any power from being made? i'll be running about 28PSI and looking for +-550WHP..

TheShodan

iTrader: (14)

No. that piping is capable of holding 550whp

/thread

Boosted_B_Series

can't he just step up the cold side to 3" and meet his goals?

Blown90hatcH

Why? 2.5" has been proven on many setups making over 700whp.

TheShodan

iTrader: (14)

He needs to keep the pressure drop down a bit, so less boost is needed to keep the car a bit responsive (or as responsive as it can get w/ 600whp.) 2.5 is fine.

HiProfile

Regarding response, I actually did the math at HMT.com, and I was a bit surprised. I can't recall the exact numbers, but when I used 2.5" and 3.0" in the formula, it was 40% extra volume but only adds 0.1 second to transient response (0psi to ~15psi) on a D16 @3500 rpm.

The key behind that is the engine consumption of air is FAR FAR greater than the volume in the piping. In simple terms, the engine is 'leaking' that air given its an air pump. In complicated terms (D16@3500rpm), to reach 15psi you roughly double the flow. That means you need the 84cfm the engine is using NA *plus* another 84cfm. Figuring 10 feet of 2.5" piping is roughly .34'^3, it only takes that extra 84cfm ~0.1 seconds to fill the piping to 15psi. This goes to show its the shaft speed that creates lag, not piping. The numbers are a tad higher since the cylinders don't wait for the pipes to hit 15 psi before sucking in the extra air.

Running925

pretty sure this was covered last week too!

Boosted_B_Series

edit: I miss read the Shodan's post, haha oops, it was late.