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How much boost on a stock head gasket?


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Hey everyone, I am posting from Vancouver, B.C. I dyno'd my car to see what kind of power I could make at different boost settings. http://home.comcast.net/~pinea...y.wmv We used a wideband to monitor air/fuel, and found it flowed fuel and actually got richer under increased boost. This was contrary to what I had been told. I was informed I would need a uprated fuel pump in order to flow the fuel for a bar of pressure, otherwise it would run lean. So now that I know I can safely run a bar of boost, I am wondering if there is a rule of thumb for headgaskets. Is it safe to run 14.5 psi on a stock head gasket? I could use a little more, or should I dial it back to 12 pounds and stop asking for trouble?

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if your using an RB20, RB25, or RB26 you should easily get away with around 20psi safely when it comes to head gaskets, perhaps even more on the RB26.

Although as far as im aware your fuel should increase as boost increases, as you need to match the fuel to the air supplied to the motor, if your running lean then i would recommend getting a fuel pump, if not then i wouldnt bother replacing something that doesnt need to be replaced.

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