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Hey all,

I own a R33 and have recently fitted my front mount, now whenever i boost the car up past 10 pound and i get the revs up to around 4500 i get a series of backfires comming from the muffler, it feels like i'm hitting rev limmiter and i loose power. I have kind of narrowed it down to these following things.

1 my computer. I'm not sure if it is only registering 7 pound when i am running 10 and only putting enough fuel thru the car the accomodate this.

2 My air fuel sensor might be stuffed up. If it is i have no idea how to get it fixed or what i should be doing with it.

If anybody has had the same problem with their car cause i have heard this is kinda common can u please let me know what you did to fix it and how much it costs.

I will be getting the car dyno tuned soon so hopefully that might also be able to work out the problem.

Thanks

Adam

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Hey, What front mount did u get put on, and how are you running 10 pound of boost, eg; electronic boost conroller, or bleed tee etc. Also did u fit the intercooler yourself, or did u have a work shop do it for you. It could be hitting your boost cut, or it could be spiking to like 16psi or somthin, also i had a similar problem when i had a Hybrid front mount kit put on my car running high boost, it would break down between 5,000 - 6,000 rpm. Also if u did get a shop to do it they should have road tested it before they gave it back to you. And also maybe you should have your car tunned before increasing boost, as it is good insurance.

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The break down your feeling is your spark plugs, You need to take them out and re-gap the size down to .7

The reason why its doing this is because under load (boost) the spark is trying to jump the gap (1.2 i think plugs are standard) but isn't getting full spark across so you need to lower the gap.

The fuel should be fine at the moment on 10psi, but dont raise the boost any more other wise you will start to lean it out and cause pistons to melt.

have fun,

:D

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