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Hey guys,

I'm looking at getting a turbo back exhaust for my r34 gtt.

I want to know what the best size is for this type of job? I was told 2.5" would be more than enough all the way through? My mate drives a 400+ hp turbo'd car and that is what he uses. He is a professional drifer.

I always thought 3" was the go for a turbo car? can anyone shed some light on this?

thanks

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Isnt the standard exhaust 2.5"??

I wouldnt go anything less than 3"

what future mod's are you going to do? and what sort of car does you mate have?

not much in terms of mods... just exhaust... air filter... induction etc

not going to be raising the boost or anything like that. Just want it as it is, but with a bit more punch.

mate drives an s13

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Definately at least 3" all the way. If you're after the best in terms of performance, then a straight-through would be it. If you wanted to stay legal then look at a jasma exhaust like the Trust PE II or HKS Silent Power (do a quick search for these on youtube).

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I use the HKS Silent Hi-Power on my R34, I'm pretty sure its a full 3" system. It has a decent note and not too droney. I'd also strongly recommend a Bosimporting highflow cat and split dump pipe which is run by one of the traders on the forum. I think his name is Batmbl, plenty of other SAU members will be able to vouch for this gear, its top quality and all fits together with no dramas! This is a pretty awesome set up that would suit your application nicely.

Jizm

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2.5inch is way too restrictive for the amount of exhaust gas you need to expel on a modded turbo car. 3inch or 3.5inch but the latter will most likely be quite loud which i don't think you'll want.

I don't think you can even buy off the shelf 2.5" kits for skylines so you would have to get one custom made and it would cost more than a 3", be more restrictive and thus inhibit performance.

I also think it's kinda odd that your mate only has a 2.5" exhaust i'd be surprised if it wasn't actually a 3".

Steve.

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If you wanted to stay legal then look at a jasma exhaust like the Trust PE II or HKS Silent Power (do a quick search for these on youtube).

umm.. isn't Jasma a brand on its own? I have a 'jasma' catback on my 33.. i never knew if it was a reputable brand or not, can anyone shed some light on this? it also has some badge on the side of the rear muffler that says 'veilside' :bunny:

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Thanks for your input guys. After inspecting the car and having another talk about it, I have decided 3" :(

On a side note... I know this has been covered before and i don't want to start up another thread, but what oil do you guys use in your 34's?

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