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Misfiring RB25det

Black R-33 4Dr
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Black R-33 4Dr Explorer

Black R-33 4Dr

Posted
Posted

Gday guys

I was wonderig if anyone out there had]s experienced the problems i am having with my misfiring engine. Currently the engine accelerates up to 3000-3500 ok. The problems then start. If I try to accelerate using full throttle the engie misfires and pops out the exhaust. It feels really flat and hesitant. Once the engine finally reaches approx 5500-5800 it takes off like a rocket all the way to the limiter. I am having thoughts on the coils and perhaps exhaust cam timing.

Mods are:

Hi flow turbo, 3" inch mandrel turbo back, plug gap 0.7, boost set at minimal 12psi,

checked A/F ratios , are fine,

If anyone has any thoughts could you please assist before i need to start spending big bucks, Knowledge in Tassie is minimal as the low volume of these vehicles.

Cheers

Nick

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https://www.sau.com.au/forums/topic/46767-misfiring-rb25det/
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EFI_fixer Newbie

EFI_fixer

Posted
Posted

Hi Nick,

Am interested to know what kind of boost you are running. Is the amount of boost dropping off at high rpm? I ask this because it is harder for a spark to jump the same gap in a higher density atmosphere. Reducing the gap or cutting back boost may prevent the car misfiring, but will put a dent in your performance as well.

I'd be inclined to try out a set of Bosch Super 4 spark plugs if you can get a set to suit, as they do provide superior ignition. Otherwise you may need to get a set of coils or an ignition module with a stronger output depending on which is holding it back.

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