When I had my head redone recently due to what I thought was a broken valve
spring, Abacus Racing found I had four of twelve springs broken. Some
inners had been broken for awhile, apparently. Same shop had done the head
for me 15 years ago and, at that time I had them mill it to give 10.5:1
compression. I wouldn't do that again. It has cost me a fortune in 93
octane gas and I had to shim the rocker stands to get valve clearance. This
time they went with single springs so they could put stem seals on the
intake valves. All back together and working fine.
Mark Anderton
72 TR6
http://members.cox.net/andertonm/car_stuff.html
----- Original Message -----
From: "Sally or Dick Taylor" <tr6taylor@webtv.net>
To: "Bill Bereza" <bereza@pobox.com>
Cc: <6pack@autox.team.net>
Sent: Wednesday, April 30, 2003 6:14 PM
Subject: Re: things to do to a head while getting a valve job
> Bill---One area to check while the head is off and valve work is being
> done, would be to check for valve guide wear. These are pressed out/in,
> and now would be the appropriate time to do this.
>
> So far as the replacing the integral cast iron valves seats with those
> made of Stellite, it's my contention that isn't necessary except
> possibly for valve trains that operate at frequent high rpm with
> stronger-than-stock springs. Have the machine shop check for valve
> recession on your seats, then decide whether to reface or replace.
>
> The stock head with the 7.5:1 ratio is a bit anemic, but has the
> advantage of being able to use the low octane fuel. For a few more
> ponies, you could have it kicked up to 9.0:1 by having it shaved to a
> total thickness of 3.460.
>
> Dick
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