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when using one of those JJR split dump/front pipes on a standard turbo around 12psi most people run into boost creep issues because of the wastegate flap fouling on the pipe

would this still happen on a highflow ?(the standard highflow from hypergear)

would preloading the wastegate make any difference? or would i have to modify the actual dump pipe

(i havnt actually seen how the wastegate fouls on the dumps so im just going of what ive read)

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It fouls on the pipe on the inside, you need to clean out the inside to clear it. (Or i did anyway) High flow of not, its still opening in the same place :blush:

My advice is to sell it, and get a bellmouth made up, or get a front pipe, and have a dump made. The splits seem to cause problems.

Even after cleaning mine up, letting the wategate clear, it was still spiking. So i got a custom front/dump made and havnt had problems since.

You call though.

well my turbos getting highflowed atm. if its just die grinding and test fitting should be fairly easy as it'll all be off the car.

It fouls on the pipe on the inside, you need to clean out the inside to clear it. (Or i did anyway) High flow of not, its still opening in the same place :P

My advice is to sell it, and get a bellmouth made up, or get a front pipe, and have a dump made. The splits seem to cause problems.

Even after cleaning mine up, letting the wategate clear, it was still spiking. So i got a custom front/dump made and havnt had problems since.

You call though.

did u get a custom split or bellmouth made up? how much did it cost?

i had a big problem with boost creep when running a split dump on my high flow. i the end i put a 2 1/2 inch restrictior plate in the exhaust to hold the boost down to 12 psi until i got injectors in and then let it go to 15 psi. i also put a bell mouth on and still boost creeped. i also think the tune had a bit to it as a rich tune will put more fuel in and cause more exhaust gasses.

boost creep sucks! on my hks 2530 on my old RB20.. ihad a split dump and boost creep was crazy.. i pissed the split dump pipe off and got a nice 3.5" made by an exhaust shop.. all under 200 $$ and now no more boost creep! the problem was the wastgate flap would hit on the small split pipe and wouldnt give it enuph room to open fully to hold the boost!

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