what do u think stroker engine and fp red or black ? 2.5" licp and 3" or 2.5" uicp would be better ?

 

^ 2.5" i would say, black doesn't require that much volume of air so 3" might be pointless

 

Just flipping through one of my books I found a section on intercooling that should help. Its a list of maximum recommended HP for charge pipe diameters.

2in - 255 hp
2.25in - 345 hp
2.5 in - 450 hp
2.75 in - 565 hp
3 in - 690 hp
3.5 in - 970 hp

*decrease max HP per 90-deg bend. three 30-deg bends equal one 90-deg bend.

The book is Forced Induction Performance Tuning by A. Gram Bell on page 155.

I assume he just calculated head loss per each diameter and flow rate (generally 9.5-10.5 lbm/min of air are required to make 100 hp), but at least it gives you a rough estimate

 

Unless you have a R&D room with a lot of time, I think it's going to be hit or miss depending on the setup.

 

look up exhaust piping size too. its so far from what people are running its absurd.

 

you do NOT need 3"

bottom line...

if you go 2.75" (stock tbody size basically) you can atleast keep it one size... add a wiggins clamp or hargett quick disconnect... atleast then you eliminate coupler swelling

cb

 

701whp going to a 75mm TB, 5" IC, and 3" piping was worth 9whp.

I have the same combo as the aforementioned car (basically) and with 2.5" pipes, STOCK throttle body, 4" intercooler, made 794.

Our drag cars use 3" but alot of that has to do with the min outlet size off of a 4202 and we use Q45 TBs. I dont think that on those cars it makes sense to run less than 3" but we have no plans on going larger either. If I wasnt so lazy I'd calculate the CFM a 2.5" pipe can move vs a 3" and the amount of air an 800whp car is actually consuming in CFM.

aaron

 

Personally, I'd say you better be using a t3 kit or above for anything above a 2.5" IC pipe...I know 2.5" personally is good until at least 600whp...

 

u mean coupler blow off, for me. haha

 

Not really its all math. This thread is a duplicate of one that was just posted its on the first page of engine turbo drivetrain. I have posted a formula in the other thread to show the difference in ci of a 4 foot piece of 3in pipe vs 2.5in. There's exactly 64.86ci of difference in the two of equal length.on the same turbo if it can't flow enough volume u are only hurting power by creating pressure drop. A buddy of mine went from 2.5 to 3 on a gst and an ic upgrade from sidemount it lost like 15 to 25 horsepower. It was definately noticeable not to mention his evo 3 turbo spool time slowed by 500 rpm. Hope this helps.

 

ahh I love the "my buddy" quotes. lol. 64.86ci is a nothing. The amount of air a turbo moves this is really a negligible difference. Secondly the 500 RPM of spool and 15-25 HP loss. Now I know there is something wrong. He's either got something else going on, or you just not straight on your facts. I vote for boost leak, which would explain the slow spool and power loss since it will be running overly rich.

stock Evo 3 engine, and turbo, upgraded from 50MM to 70MM pipping (turbo to throttle body), upgraded to precision 600hp intercooler 31.5x8.3 from stock 18x10x2.5. Logged 80-100 RPM spool loss (barely noticeable on the butt dyno), and no noticeable power loss or gain, but back to back runs netted 10 counts less knock at 1.3 bar. If you want to really figure this out and compare numbers, be my guest.
If your buddy regrets upgrading to a front mount, then he can send it to me, I will put it to good use.

 

Ya u sound like the other guy in the other thread that said to turn boost up to compensate for the pressure drop lmao. If I remember correctly we checked for boost leak after his car fell on its face. After reinstalling the stock ic and piping the power magically came back. And sorry for a my buddy quote. If it had happend to me I would glady say it did but it didn. U contradict urself tho. Y would hp rating on an ic matte like ur precision 600 hp ic but ic piping not matter? Is the size of an ic relevant to hp I think so. To big of an ic is doing nothing. Same for ic piping. Its all relevant and common sense.

 

I just looked and it was u that posted in the other forum we should turn the boost up to compensate for pressure drop sucha great idea

 

And 68 ci not much that's almost 6 cubic feet more of air space on just 4 foot of pipe. Now let's see his ic piping in all is close to 7 or 8 feet so that's doubling it to almost 12 more cubic feet not to mention his ic. U said urself on ur setup u didn see a loss BUT u didn see any gains either besides less knock. How is him losing power hard to believe when the example I gave was for 2.5 vs 3in when u and I know neither of those are stock size for an eclipse its more like 2 in stock so technically the 68 ci is not correct it would be even higher with an even bigger pressure drop meaning? POWER LOSS NOT BOOST LEAK. But we will remember to just turn the boost up to like 30 psi next time to compensate for it.

 

If I may, 68in^3 = ~.04ft^3. It takes a fraction of a second to pressurize the volume.