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Hey guys, I just put the rb25de into my S13 and was thinking of welding up an r34 turbo exhaust system to it (sitting in my shed) How do you think this would go? obviously its designed for a turbo motor but by rights it should flow pretty well on an rb25de and be nice and quite? or would this just be fail?

If you're going to the trouble of cutting it up and welding etc, make a proper 2.5 inch mandrel bent system with a good muffler. If you want to keep it cheap just use lobster back bends, but do them well and it'll be just as good for the application.

Ps, a r34 exhaust won't fit an s13, not even close afaik.

i assume your talking cat back?

does ti even fit properly under the S chassis

wouldnt you just get a propper one made after going through the effort of an engine change?

The engine change was piss, its just making everything else fit. I honestly don't know if the r34 exhaust will fit (and yeah from the cat back) I haven't seen if it will fit yet.

EDIT: unrelated question, are knock sensors needed to start the engine? I cant seem to find the harness.

Edited by Gameboy

Seeings as it an N/A, you greatly benefit from a bit of back pressure for better low down torque, so don't go too big or it'll be all noise & no go!!!

2.5'' is too big for N/A, I'd look at 2'' as absolute maximum

A free flowing exhaust is a compromise. Maybe you could follow the Ferrari/Lambo/SLR route & have an exhaust cut out for higher RPM when it's all about flow........

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