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R33 Top end power problem

JULZA

By JULZA,
in Engines & Forced Induction

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JULZA Apprentice

JULZA

Posted
Posted

I've got a R33 GTST running a R34 turbo. The car is pretty much stock other than the cheap mods.

Has anyone had a problem when the trubo spools up to full boost that the car gives a struggling sound and can even shudder a bit?

This problem has only started now and happens even on stock boost levels.

My initial thought is that it's leaning out, but I've got a GTR fuel pump so I'm not sure.

Any help would be much appreciated..

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https://www.sau.com.au/forums/topic/62311-r33-top-end-power-problem/
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cameron Mentor

cameron

Posted
Posted

If you have front mount cooler/Dumpipe/Exhaust done, it should be breathing fully and not strugling uptop.

Leaning out won't make it struggle - as you said you have a bigger fuel pump and with stock R34 turbo - it should'nt lean out.

What boost are you running & what else is done to the car ?

:cheers:

Jun

tang0 Proficient

tang0

Posted
Posted
Do the dumpipe from the turbo to cat.

 

&

 

Front Mount Intercooler.

 

Maby try changing you'r spark plugs aswel.

 

This should help.

 

:P

Jun

theres a grand easily !!!

might just be worth changing the fuel filter ... often overlooked, but can often be a cheap quick fix as well if the current one is full of cr@p

JULZA Apprentice

JULZA

Posted
  • Author
Posted

The spark plugs were just changed, the platinum kind which cost a packet!

The Fuel filter sounds like a possibility cause I dunno when it was changed last.

The rpm doesn't show any signs of struggling when the problem occurs, the other thing is that if I put my foot down and bring the boost just a little shy of full boost it's fine.

So it only happens when I floor the car. The car doesn't really shudder as such it's more of a audible issue and power drop out (from the turbo). When at full boost it's as if it is being floored then eased off then floored, so it cuts in and out of sounding like normal.

It's bloody hard to describe but it's never happened before and annoying.

I'll test the fuel pump flow and check out the fuel filter and let you know.

joh21m Collaborator

joh21m

Posted
Posted

sounds a lot like the problem i have now with my rb20det...when i hit 5500rpm, power drops from 122rwkw to about 80rwkw, mechanic has suggested new coil packs which i ordered about 5 weeks ago and still havent arrived. I dont think its gonna fix the prob but i will let you know how it goes...

maybe you should put it on a dyno aswell...i found my car is running super rich as SK pointed out, im looking at an safc to correct this...

i'll let you know how it all goes...

Joh

fresh Rising Star

fresh

Posted
Posted

too much boost on the stock ecu, it'll pull the timing and and dump in fuel like a bitch, dunno your problem might be worse then that but the stock ecu don't like much more then 10psi, maybe its time for an aftermarket ecu, u seem to have done everything else

JULZA Apprentice

JULZA

Posted
  • Author
Posted

yeah,

I've thought about grabbing an apexi AFC but cost is an issue.

The reason that I don't want to go down the computer path is because it was running high levels of boost with no problems for ages, and now on stock boost it does it so it can't be the stock ecu struggling.

  • 2 months later...

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