Hitting rev limit with WI...
#1
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Hitting rev limit with WI...
Ok, read over the DO kit instructions.....seems simple enough. My only worry now is the "caution" notice in the adobe instructions to hitting the rev limiter (fuel cutoff). Has anyone hit the rev limiter with the WI on? Is this something to worry about if I set the pressure switch to say 4psi?
#2
nope nothing to worry about when you hit the limiter the boost goes down and the pump turns off even on quick decel ie sudden braking during boost ramp up or while at max boost the pump response is pretty quick and no harm should come to your motor they put that there to cover there *** most likely not that it would happen. And even if it did worst plausible scenario i can see is stalling the car and doing a caost restart or just twisting the key to fire it back up. So on worrys man
#3
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I'd never considered this before, but I can see the logic in it.
I don't know exactly how the rev limiter in the Miata is configured, but consider the following hypothetical:
In actual practice, I have hit the limiter many times while running roughly a 30% by volume meth-to-water ratio, and my engine seems none the worse for it.
I don't know exactly how the rev limiter in the Miata is configured, but consider the following hypothetical:
The design of the Rev Limiter is such that when activated, fuel is cut off but ignition continues to operate. You are running an injection mixture which contains a very high proportion of methanol, such that the mixture can support combustion in the absense of gasoline.
As you hit the rev limiter, the gasoline supply is shut off, but the methanol supply continues. Since the ignition is still active, the engine begins to run completely off the methanol. Unfortunately the relatively small amount of methanol present results in an extremely lean A/FR, and you soon break a piston. You then become pissed off at Chance because he didn't warn you not to run on the rev limiter while under methanol injection. In actual practice, I have hit the limiter many times while running roughly a 30% by volume meth-to-water ratio, and my engine seems none the worse for it.
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If they cut spark only, but left fuel on, then raw fuel would flow into the exhaust system, through the cat, etc. during a rev limit condition. This would result in a backfire or explosion when the spark came back on.
Spark and fuel seems plausible. Actually, if anybody here has an EMU with their CAS lines connected (mine aren't) we could pretty easily figure this out just by datalogging a rev-limit event.
Spark and fuel seems plausible. Actually, if anybody here has an EMU with their CAS lines connected (mine aren't) we could pretty easily figure this out just by datalogging a rev-limit event.
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