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I have r33 Gtst - just had work done including - hi-flow turbo, timing belt, fuel pump, apexi pfc have intercooler, exhaust 3" etc. On cold start up, sounds like top end noise like a woop woop woop woop woop in quick sequence - difficult to explain but i thought maybe it was the new timing belt? It goes away when the engine is warmed up, any ideas?

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Yer but where exactly do you mean grab it Duncan? :P

Ive got new tensioner bearings (i run two on the 3Lt) and a new belt (although it is the rb30det belt) and it has a whoop whopp noise as well. Most nticable on cold starts, but there some other times as well.

Ive heard of a few rb25's that have the same thing, but the weird thing is nothing is wrong -they are all tensioned and setup properly, just noisy.

Edited by Bl4cK32
  • 3 weeks later...

Hey,

Got another one for yas! Got a noise in the exhaust. Had the whole exhaust system done about 4 months ago. It was done at formerly Hardcore Racing in moss street. about 2 weeks after the install I noticed this rattling noise. Checked it out and it sounded like it was coming from the mid pipe like some shards of turbo or something were blocked at the hi-flow cat. I disconnected the cat and found their to be no shards or anyhting forward of the cat. I then also noticed that one of the bolts where the turbo joins to the exhaust had been sheared off or was missing. Firstly, is it common for the RB25 to have this happen and second, could this possibly account for this rattling noise which like i said sounds like something like shards of metal flying around in the exhaust?

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