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Just Jap Split Dump/front Pipe

DAV-R32

By DAV-R32,
in Engines & Forced Induction

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DAV-R32 Collaborator

DAV-R32

Posted
Posted

hi everyone,

i was wondering if anyone has bought or all ready got one of those just jap RB20 split dump/front pipe on their car.

Im planning to get one and a high flow cat they got on sale for $160. Just want to know how good is the craftmanship,

performance wise- any difference ? does it turn purple afterwards and the metal turn out crappy etc etc.

iam not sure if i should buy one from just jap or the group buy that is on at the moment.

any information will help guys so leave a reply :D

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https://www.sau.com.au/forums/topic/204729-just-jap-split-dumpfront-pipe/
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-33- Community Regular

-33-

Posted
Posted (edited)

I got one (its not on an RB20, its on an RB25). I bought it as part of a full turbo-back exhaust system from Just jap, with the high-flow cat.

Performance-wise, i noticed a BIG difference to be honest, especially up high in the rev-range. Definitely lets the turbo breath a bit better. Its still going fine for me (haven't had a look to see if its gone purple though), and the craftsmanship seemed pretty decent when i inspected it after purchase. I fitted it myself with a couple of mates (at 2 am in a shopping car park LOL) and had a tiny bit of trouble bolting the dump up. Just make sure u use the couple of the gaskets that are provided, as well as the stock metal one to make sure theres no leaks - otherwise it may come a bit short.

Heaps of people will argue for/against the split till the cows come home. My opinion is that the split arrangement should theoretically improve transient response: although the wastegate & turbine gases do ultimately meet anyway where the split pipes merge into the front pipe, the initial twin piping should help to keep the gas streams separate. This in turn reduces turbulence directly adjacent to the turbine and allows your turbo to work that little bit easier.

In any case, its definitely an upgrade over the stock item you've got.

hi everyone,

i was wondering if anyone has bought or all ready got one of those just jap RB20 split dump/front pipe on their car.

Im planning to get one and a high flow cat they got on sale for $160. Just want to know how good is the craftmanship,

performance wise- any difference ? does it turn purple afterwards and the metal turn out crappy etc etc.

iam not sure if i should buy one from just jap or the group buy that is on at the moment.

any information will help guys so leave a reply :D

Edited by -33-
gotRICE? Veteran

gotRICE?

Posted
Posted

I have one on my R33 25-t, performance wise like the others have said it feels like a big improvement up high.

Only issues i came across was one of the bottom bolts is tricky to do up because of the immediate bend of the dump pipe. It IS possible tho, you just need to use your head :cheers:

And the turbo water feed is kinda "leant" on by the dump pipe and manifold heat shield.

After 1st installing it i got mass amounts of white smoke burning off it, that went away pretty quick. When a sexy gold colour, then obviously got damp, as it will, and got a purple tinge to it.

Whoe cares tho. You cant really see it with a stock turbo and heat shield.

geraus Mentor

geraus

Posted
Posted

i got one with CATCO 3'inch high flow cat, with Trust/Greddy 3'inch front dump pipe, 3'inch Greddy/Trust PEII extreme with some brand split dump pipe from the turbo... and i tell ya the improvement is excellent!

Levi_ Proficient

Levi_

Posted
Posted

Just fitted one to my r33 last night, along with a de-cat pipe. The quality is pretty damn good and I managed to fit it with a friend without any major hassles (nothing but hand-tools) in about 3 hours. Haven't had a chance to take it for a good drive yet, but I assume it'll have my car running even more lean than before.

gotRICE? Veteran

gotRICE?

Posted
Posted
Just fitted one to my r33 last night, along with a de-cat pipe. The quality is pretty damn good and I managed to fit it with a friend without any major hassles (nothing but hand-tools) in about 3 hours. Haven't had a chance to take it for a good drive yet, but I assume it'll have my car running even more lean than before.

So what did you guys do with the water line?

W0rp3D Grand Master

W0rp3D

Posted
Posted

Im looking at putting one of these on when i upgrade my turbo, just wondering if anyone has thought of tapping into the external dump pipe from the wastegate and putting and external wastegte in there and removing the internal flapper, will this give better boost control?

-33- Community Regular

-33-

Posted
Posted

^^^ Well there's heaps of split dump pipes out there that have an open wastegate pipe (i.e. not welded back into the front pipe like an ordinary split). It probably would help surge and give better exhaust flow as well. Have a look and see if you can find anyone running one of those. Although if you are getting an aftermarket turbo and are thinking of that sort of setup, why not just get an external wastegate?

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