this just might be my problem...not apart yet, more to come. clyinders have
some nasty scrathes in #3 and #1 also..rings might have broken creating a
very hot spot..but i WAS generous with the gap! more to come.
-----Original Message-----
From: Larry Dent [mailto:lwdent@fwi.com]
Sent: Friday, November 07, 2003 10:03 AM
To: Carl Braun
Cc: Kansa, Robert; team-thicko@autox.team.net; VintageRaceNet
Subject: Re: Venolia Piston Failure at Mid Ohio
The new high eutectic (spell ?) low expansion pistons require a HUGE end
gap on the top piston ring. a 4 inch piston in a 289 requires almost
.040 gap because the piston reflects so much more heat down into the top
ring that the expansion is huge. We used to gap those rings at more
than half that figure with forged pistons.
I am building an extra engine for my GT 40 right now and I was
astonished at the gap I had to run in Keith Black pistons, but just on
the top ring.
Larry Dent
PS. To add one more comment on the question about horse power in the
old twin cams. I ran an HRE (Gus Hutchenson out of Texas) 1300 cc twin
cam in my Lotus 23 back in 1969 to 72. That engine was very exotic with
titanium valves and other pieces made of un-obtanium and it made 155HP
at 11,500 RPM. We were all sworn to silence on that high RPM as Gus did
not want anyone knowing what he did or how he did it. I once missed a
shift and put the tell tale to around 12,500 and when I called Gus he
said "don't worry, the engine is safe to 13,000 on a momentary basis".
That was in 1969 folks.
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/team-thicko
|