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Turbocharger intercooler piping size

KalebM

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So i just recently bought a t3t4 turbo and from what i know it is 2” off the turbo into the intercooler piping would i keep all the piping at 2” or should i get a connection for 3” intercooler piping
 

Pollushon

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What's it going on? There's a few variables but some pretty solid calcs based on the flow rate and your power goal.
 
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KalebM

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So its a vt commo and i was looking at 10psi tops i recon, i dont plan on putting through to much boost
 

_R_J_K_

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General rule of thumb I've seen on a lot imports is turbo outlet sized piping to the intercooler, then T/B sized piping from the outlet of the intercooler to the T/B. By going bigger on the hot side you introduce more volume that you need to fill up before you hit boost. By making it the same size as the outlet you're not restricting flow and minimising volume. TBH though, the lag wouldn't really be noticeable if it was a short length of piping (and even then really if it was long).

Are you going to tune it?
 

KalebM

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Yeah i am before dont wanna **** anything up with not enough fuel and **** most likely ill get a aftermarket ecu instead of tuning the stock one, and cheers that helps heaps
 

Pollushon

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You'll wanna up your pump lph for boost, there's no getting around it. OEM pump will leave you short. Walbro 342 and an fpr800 reg works a treat up to about 18psi. Stock delco is more than sufficient for a stock Eco just needs the right tuner.

This vid is the best I've seen on explaining pipe sizing but your intercooler size is important too. Balance of velocity, turbulence and lag. Sometimes it's just balancing the wallet though.

 

KalebM

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Yeah ive just been looking at that knew i had to upgrade the pump but i thought that i would also need to upgrade the injectors correct? Cheers for the video ill check it out when i get the chance
 

KalebM

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So ive been recommended to probaly keep the boost under 7-8max for my engine would you know what size injectors i would need for that by chance?
 
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