FMIC pipe size vs. Spool time

[Cody D]

I had a local bending shop with a mandrel bender make my intercooler piping for me, I guess I didn't specify the size of the piping that I wanted, they made the piping about 2" when I wanted 3", it was my fault.

My question is... if the inlet and outlet on the intercooler are no bigger than ~2" then is there much point in having 3" pipe or will it just increase my spool time? I'm sure that the flow of the 3" would be better, but with the bottle neck of the intercooler would it really be a big enough difference to have the slightly slower spool? The other factor is that I'm planning on going with an FP Green for a turbo fairly soon, would a turbo that big need 3" pipe?

 

[DSMJim]

2" will be too small it simply won't flow enough air, 3" will be over kill. 3" pipe flows over twice as much air as 2" pipe does. The larger pipe will not cause lag that you will notice, it is just too large and a waste of money.

YOu want 2 or 2.25" from the turbo to the inlet of your cooler and 2.25 or 2.5" from the intercooler to the throttle body.

On my car I still only have 2" from turbo the cooler and 2.25" from cooler to throttlebody and I pull good times. I do think however that I will need to go up this year, but im gonna try and hit mid 11's on those pipes and see what it does ...

 

[Cody D]

You've confused me a little bit... you say that 2" will be too small, then you say that I should use 2" from the turbo, and 2.25" from the intercooler? Are you saying that I should just upgrade my intercooler to throttle body pipe? Is 3" overkill for the FP Green or just my 14b?

Also will it be worth the money and the pain? The thing that I guess I'm most worried about more than money is trying to fit any larger pipe into my already confined engine bay, but I guess if I'm only going up a quarter of an inch on one of the pipes it won't be too bad.

 

[BluemeanieTSi]

i dont' see 3" on too many cars...mainly drag cars with air/water Ic's

 

[anconover]

3" is far from necessary. Your intercooler inlet/outlets probly arent 3", and your t-body isnt 3".....

you want 2.5" piping. If your core has 2.5" on both outlets, do 2.5" from the turbo to the tbody. The smaller piping people just tend to use because its easier to adapt to the turbo. Just get a reducer.

 

[MigTalon]

I'm using 2.5" aluminum for lower pipe and 3" aluminum for upper pipe... I think that air volume depends most on what turbo U are using, then it has to be matched with IC pipes and Intercooler Core that will let "AIR VOLUME" flow through the system. 3" in the upper pipe will help to lower "intercooler pressure drop".

 

[Cody D]

Thanks for the answers. I'll have to take the pipe off and measure to see what size they actually are.

 

[UPGRADED2G]

i got a 2.25 upper and 2 lower......works fine with my t25. sounds like a 2.5 upper and 2.25 lower or a full 2.5 should be adequate enough for your green. my IC kit just came and i have all 2.5 pipes so i guess ill eventually have to switch to a 2.5 upper.....it would only make sense!

 

[DSMJim]

You've confused me a little bit... you say that 2" will be too small, then you say that I should use 2" from the turbo, and 2.25" from the intercooler? Are you saying that I should just upgrade my intercooler to throttle body pipe? Is 3" overkill for the FP Green or just my 14b?

Also will it be worth the money and the pain? The thing that I guess I'm most worried about more than money is trying to fit any larger pipe into my already confined engine bay, but I guess if I'm only going up a quarter of an inch on one of the pipes it won't be too bad.

I'm saying all 2" piping all the way around is too small. I have a 50trim which is a Green from FP and I use 2" only from the turbo to the intercooler and 2.25 from the cooler to the throttle body and have laid over 420whp and gone over 115mph traps so 2.25 upper and 2" lower will be enough for you, though a 2" upper will be too small.

The best will be 2.5 however but 3" is overkill and not needed.