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guys+ girls, ive got a r31 gtsx with a silver cover rb20det in it and ever since i did this conversion it has had a intermitant surging problem when cold! If i flatten it, it revs up very slowly and then boosts suddenly(goes sideways!) change into second, same thing, third, same etc. after about 3-5 minutes of driving it disapears! wtf is going on?

thanx people

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Flattening it when its cold hmmmmmm..........Not good!!

I think it uses a differant map when cold, which is richer to help get it up to temp quicker. A bit like a choke I think - but correct me if I am wrong. It could be because its running heaps rich, it bogs down a bit then takes of ?

Best bet would be to keep it quiet until its up to temp I reckon

Had a similar problem in my GTS4 - its like someone riding the brakes, right?

My local Nissan dealer told me the timing was retarded to buggery, so I'd suggest you check that first.

and, for crise sake, DON'T boost it when its cold - unless you've got heaps of money to replace the engine..

Guys, it is just the engine warming up, I have exactly the same on my 32 in the morning.

Just don't rev over 2500 for the first 3-5 mins of warm up and you're away!

Boosting when cold is murder on your engine/turbo, like when you put hot water into a frezing glass or vise versa, CRACKS!!! And you don't want to crack your exhaust housing or any other part of your engine...

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