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Power Loss On Downshifts, Bouncing Idle And Slight Hesitation At Specific Rev Point -R34Gtt


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Gareth, you have put 300k KMs on your 25, what are you doing laps of Australia or do you live in your car cause dam !!!!

I've owned my car since 2002. when i bought it it had 134,000kms on it. i've still never lifted the head off the motor and i've done all the maintainence myself....most of the problems are with the ancillary parts of the motor failing over time e.g turbo....

If you keep standard internals its well within the realm of possibility.

So you are saying it is possible with a blown 25 to build a 25/30 on the road for that price? Don't think so. Not even close.

My bet is that your highly strung 4G63 will grenade long before my 25 will! Crankwalk anyone? :woot:.. Mick O

Edited by rondofj

Lol care to place money on that Ronaldo? Dunno how its more highly strung? Im running a pound or 2 more boost than your car on Ethanol with a lower comp ratio and probably make similar to a little more power than you.

Its just a better designed more efficient engine than the old RB :)

Lol care to place money on that Ronaldo? Dunno how its more highly strung? Im running a pound or 2 more boost than your car on Ethanol with a lower comp ratio and probably make similar to a little more power than you.

Its just a better designed more efficient engine than the old RB :)

agreed, RBs are old dinosaur tech

Where did they over engineer it?

Certainly not the oiling system....or the cooling system....or the cylinder head....or the turbo chargers......did I mention the oiling?

Stock engines weren't designed to rev at 8500 rpm for 10 secs bouncing off the limiter at double the intended boost. Do that to most engines and you will kill them.

Edited by XGTRX

My bet is that your highly strung 4G63 will grenade long before my 25 will! Crankwalk anyone? :woot:.. Mick O

Micko Atleast knows where his timing is sitting... Just saying.
  • Like 2

So you are saying it is possible with a blown 25 to build a 25/30 on the road for that price? Don't think so. Not even close.

Yes, and I know this because I have done it. Thanks champ.

Same here. Stock bottom end untouched. All up less than 700 including oil etc for everything including retune. Took a whole week working on it a bit after work.

Not what I would call built though, as it's untouched.

But.... I know what I'm doing.... can set timing etc :)

Can't really see the point building one when a 200 buck engine does aso well!

Edited by Ben C34
  • Like 1

Sorry my bad. I assumed that going a 3L you would upgrade the supporting mods, water and oil pump, timing belt, clutch and at least a dyno tune. Obviously not the case, I apologise.

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