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Re: Air/fuel ratio monitors

To: <spridgets@autox.team.net>
Subject: Re: Air/fuel ratio monitors
From: "Glen Byrns" <grbyrns@ucdavis.edu>
Date: Fri, 27 Apr 2007 10:14:58 -0700
This time around I'm using forged Venolia pistons.  Modifications included a 
slight lowering of the top ring, 13cc dish to acheive the desired CR, and 
ceramic coated crowns.  The first blown set was due to detonation which I 
didn't hear.  We were on a SWAG ride in the Clearlake area and I was 
pressing VERY hard.  A piece of the piston wall between two rings broke off 
and gouged the cylinder wall.  The second set was retired in poor shape when 
I decided to go with forged pistons and lower the compression ratio.  I find 
that I can't run more than 5deg. adv. static and have limited the dizzy 
advance to 28deg.(if I recall correctly).  I slipped various bits of brass 
tubing over the limit post inside the dizzy until its diameter was 
sufficient to stop the points plate at 28deg.  I had the dizzy machine at 
that time and it was great for that.

This time around, for the Lake of the Ozarks trip, I will stay with the same 
CR, put in the MSD ignition and if I have enough time, switch over to 
Megasquirt.  If I can get this setup done in time it should allow me to run 
a bit more advance, back off the rich needle approach to piston protection 
and keep all the HP with an improvement in mileage.  Creaming 1380s without 
excessive overbore or lumpy cams is a good thing.


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