Correct A:F Ratio @ WOT?

[Bruce]

  Max power on my GN, is at around 11.6..
I can run it at the 12.5 but power is signifigantly down, thou all
indicators are the engine is happy there.  In dropping to the 11.6, boost
dropped some which shows the EGT dropped  some.  In twisting the boost back
up there is a bunch of HP.
Bruce



From: "Matt Beaubien" <mrbeau0 at yahoo.com>
Subject: Re: Correct A:F Ratio @ WOT?
> Bruce,
> > So what do you offer?.
> > Tuning for less then best, will generate excess heat, and carbon flakes.

> Optimum power on a highly turbocharged engine will be near 12.5:1 AFR.  To
> maintain this for any length of time on pump fuel would require retarding
> the spark a bunch to fight preigntion/detonation, which would raise
exhaust
> temps.  These high exhuast temps will then proceed to tulip exhaust
valves,
> crack manifolds, and wreck turbos.  The solution?  Run more fuel and more
> timing (obviously without detonation).  The engine won't make as much
power,
> but I'd rather deal with a bit of carbon build-up vs melted pistons.
> Matt.


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