Hx35 and size of intercooler pipes?

[talonsteve25]

My winter projects to finished the car with the intended hx35. Im shooting for 20+ psi and am not sure what size intercooler pipes to buy? I have 2.5 inch but would 3 inch be more suiting? Especially with a SMIM and biggest tb i can find. I herd of running smaller pipe from turbo to ic, then bigger pipe from ic to tb? Not sure though. Any suggestions appreated! And searched with no luck.

 

[RadDsm]

2.5" IC pipes will be just fine, and the stock throttle body will be fine too. Or a 1g throttle body.

 

[95GreenGSX]

2.5" IC pipes will be just fine, and the stock throttle body will be fine too. Or a 1g throttle body.

x2, I see people go with 3" UICP and 2.5" LICP, but I dont see the reason to that. Expecially if your only going to be boosting 20lbs and on the stock tb, there is no need to spend the extra money on 3" piping when you already have 2.5". Spend the money on something better.
Just my $.02

Ill be running my hx40 with 2.5" or 3" piping depending on what tb ill be running. Hopefully, ill be boosting to 30psi.

 

[talonsteve25]

So 2.5 inch pipe is plenty for what im doing then? I do want a different tb anyway though my 1g tb is a bit screwy

 

[viperlp01]

The hx 35 dumps to 2.5 so i ran 2.5 all the way up...

 

[ApexVIII]

if you are in the 20-30 range then i would think 2.5" will be fine,

im running 28psi on my HX35 with 2.5" piping, now if you were wanting to run 30+ then i would say 3" for sure

 

[907dsm]

Yesir

 

[gstryyder]

2.5" pipes stock throttle body.. good to go. don't need it any bigger you will just hurt spool and may end up with some pressure drop.

 

[talonsteve25]

guess i hav my answer

 

[doctor_shock10]

post some results on that hx35 if you can. and ya you have your answer 2.5 is enough.

 

[abaum565]

if you are in the 20-30 range then i would think 2.5" will be fine,

im running 28psi on my HX35 with 2.5" piping, now if you were wanting to run 30+ then i would say 3" for sure

I would say pressure has little to do with it. The volume of air you are pushing plays a much bigger part. A 16g at 30 psi doesn't push as much CFM as a larger turbo at the same psi, which would require larger intake pipes.

Now the hx35 (7blade) just for sake is about ~60lbs/min max, even with that much air going through the system, intercooler pipes are the last thing I would look at to make it more efficient. What about intercooler core design, end tank design, and the amount of bends in the pipes are things I would do before larger pipes.

FYI - I just started tuning at 35 psi on my hx35 with 2.5" intercooler pipes and it's just fine.