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Re: Power struggles

To: dterrick@pangea.ca, faustus@inconnect.com, spitfires@autox.team.net
Subject: Re: Power struggles
From: ScottBarr8@aol.com
Date: Thu, 6 May 1999 19:20:25 EDT
Thanks, Dave -- you and I think alike.  I, too, had concluded that this was a 
mixture issue.  We adjusted it richer, without effect (except sooting up the 
back of the car at lower revs).  We changed to the richer needle which Rimmer 
Bros. supplies with its header and sport exhaust systems, again without 
effect.  Thinking it was dry bowls, we jacked up the float until fuel started 
gushing out and flooding the motor.  Tried a new (different) fuel pump 
without any change.  We'll be changing to an electric fuel pump and larger 
diameter tubing to use with the Webers

I think you could be correct about the weak spark, as well.

The part I didn't mention is that this is the engine which we discovered has 
the TR6 head on it with the great big combustion chambers, giving like 7.5 or 
8.0:1 compression in the 2.5 motor -- in the 2-liter, the compression is even 
less (roughly 20%? ;-) -- like 6.2:1 or so).  I'm thinking this low 
compression, combined with a weak spark and maybe dry bowls might be the 
sources of the problem.

Maybe Andy has one or more of these issues working against him as well.  
Andy, certainly I'd recommend trying the plug out procedure which Dave so 
ably described.  It was inconclusive in our case, but might show you 
something which leads you to the solution.  Our solution was to pull the 
&$&%&$% thing apart and rebuild it so that we're starting from a known 
quantity.  The DPO's little gift of a TR6 head was a surprise.

Scott

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