Will I notice a difference between 3" and 4" intercooler piping?

[BigRich954RR]

Originally Posted by chuntington101

anyone got any answers/imput to this question???

Originally Posted by chuntington101

All i was after was someone to give me some CFM numbers for the pipes using PV=NRT and asuming you have a maximum air speed of 250ft per second @ 20psi......(cant rember the veriables)

sorry if i didn't make that clear.

the reason i ask is i know STS guys have problems with the piping they run once they push past about 700rwhp. now if we know that a 3.0inch pipe can support say 125lbs of air per min then you know you can run a 3.0 inch pipe on a 1000bhp setup.

basically just trying to understand at what point, BHP wise, you need to run bigger piping.

Cheers

Chris.

Thats what i mean a there no standed for pipe flow in a engine to = hp. A 1 foot 3inch pipe might flow 300 lbs of air but the same 3 inch pipe that 15 feet long might only flow 150lbs. Now take the 15 foot long pipe and flow 200 degree air though it might only flow 100 lbs now

When you get into boost the cfm flow changes ever thing raw flow numbers mean alot less a 2.5 inch pipe car in FL might only make 600 hp but same car in canada on a cold day might flow enough for 800hp. The flow of the pipe stays the same but the density of the air changed

Can it be figure out YES but you need every last spec and detail. then you have to pay some one to sit there for a few hours to mock it out.

ME degree in a good college is about 65 grand

[chuntington101]

Originally Posted by BigRich954RR

Thats what i mean a there no standed for pipe flow in a engine to = hp. A 1 foot 3inch pipe might flow 300 lbs of air but the same 3 inch pipe that 15 feet long might only flow 150lbs. Now take the 15 foot long pipe and flow 200 degree air though it might only flow 100 lbs now

When you get into boost the cfm flow changes ever thing raw flow numbers mean alot less a 2.5 inch pipe car in FL might only make 600 hp but same car in canada on a cold day might flow enough for 800hp. The flow of the pipe stays the same but the density of the air changed

Can it be figure out YES but you need every last spec and detail. then you have to pay some one to sit there for a few hours to mock it out.

ME degree in a good college is about 65 grand

I see your points mate. i guess it is down to each application rather than what BHP you plan on running.

Just wondered if it was like exhaust though where they say oh for xxxbhp you need a 'something' inch exhaust. if thats not the case for the intake then no worries.

Chris.

[chuntington101]

Originally Posted by Tricked-Out-Toy

Where did the 250fpm come from? At 250fpm a 3" is only 12.27cfm and a 4" is only 21.81cfm??

Feet per second mate!

i cant rember the guys but it was on one of longrange4u's threads. He was talking about how restrictive the stock STS pipe work was on the cole side. Someone said you want to keep air speed below 250 feet per second as thats when you start to encounter problems. I think Zombie for longrange did some calcs and figured they where nearly in the 400 feet per second range!!!

Chris.

[Tricked-Out-Toy]

Originally Posted by chuntington101

Feet per second mate!

i cant rember the guys but it was on one of longrange4u's threads. He was talking about how restrictive the stock STS pipe work was on the cole side. Someone said you want to keep air speed below 250 feet per second as thats when you start to encounter problems. I think Zombie for longrange did some calcs and figured they where nearly in the 400 feet per second range!!!

Chris.

Reading comp owns me.... Thats a big difference lol. 250fps is 15000fpm. At 15K fpm your looking at 736.3cfm through a 3" pipe and through a 4" your looking at 1308.9cfm.

At 400fps your looking at 1178cfm through a 3" and a 4" is at 2094cfm.

If your feeding lets say a 408 your looking at needing about 1500cfm at atmospheric pressure spinning to 6800rpms. So on a 3" setup your going to have to push past 400fps to about 534fps.... Thats moving some friggin air but thats only if you can overcome the headloss though the 3" pipe.. Your looking at about 660in.wc/100' head loss

[chuntington101]

Originally Posted by Tricked-Out-Toy

Reading comp owns me.... Thats a big difference lol. 250fps is 15000fpm. At 15K fpm your looking at 736.3cfm through a 3" pipe and through a 4" your looking at 1308.9cfm.

At 400fps your looking at 1178cfm through a 3" and a 4" is at 2094cfm.

If your feeding lets say a 408 your looking at needing about 1500cfm at atmospheric pressure spinning to 6800rpms. So on a 3" setup your going to have to push past 400fps to about 534fps.... Thats moving some friggin air but thats only if you can overcome the headloss though the 3" pipe.. Your looking at about 660in.wc/100' head loss

Cheers, what are the presure for the above???

[Taubr Unit]

any updates on this? Im tore between 3'' and 4'' myself.