Richard, the crack between #2 and #3 cylinders between the water
holes is no big deal, don't worry about it.
I run bronze guides. You just need enough valve to guide clearance
that you don't stick a valve and they work fine. Don't use valve
guide seals either.
I had them put 0.003" clearance on my intakes and 0.0035" on my
exhausts. I remember Greg having good recommendations in this regard
too, so am interested in his view on the proper clearance.
I was running 190 degrees at Road Atlanta and didn't stick a valve,
so was pleased with that.
The spring pressures should be specified by the cam builder. The
Larry Young cams want about 100 lbs seat pressure. Ones with more
dramatic opening events may want more, but that's largely to prevent
valve float at higher RPM than you run.
If you are having the seats ground, ask for a triple angle or
radiused grind - I've been told that those can make a big difference
in flow. My (newly prepared) head was milled 130 thou, I cleaned up
the combustion chambers a little to remove any sharp edges primarily,
they cut off the exhaust valve guide flush with the top of the port,
and I had a triple angle grind done. NO porting whatsoever was done
to it. I'm not sure I could tell the difference in power between
that head and my old Comptune / Uncle Jack's porting services head.
Tony Drews
At 08:19 AM 5/11/2012, Richard Taylor wrote:
>Greg,
>
>I am doing a valve & guide job on my TR-4 head. My cam is a Babe Erson
>BFE-149 with intake of 430 and duration of 282. My normal shift point is
>5000 rpms with a never exceed of 5500. Inasmuch as I drive my car to events,
>reliability, not brute power, is the game plan.
>
>May I ask your recommendations on valve guides (bronze vs. iron), their
>clearances and spring pressures? What about multi-angle valve grinds?
>
>Another issue. I found a conspicuous crack between the center 2 water
>galleys between #2 & #3 pistons. It looks as if it's been there forever and
>does no harm. Does that render my cylinder head toast?
>
>Thanks,
>
>Richard Taylor
>TR-4 #196
>_______________________________________________
>fot@autox.team.net
>
>http://www.fot-racing.com
>
>Donate: http://www.team.net/donate.html
>Archive: http://www.team.net/archive
>Forums: http://www.team.net/forums
>Unsubscribe: http://autox.team.net/mailman/options/fot/tony@tonydrews.com
_______________________________________________
fot@autox.team.net
http://www.fot-racing.com
Donate: http://www.team.net/donate.html
Archive: http://www.team.net/archive
Forums: http://www.team.net/forums
Unsubscribe:
http://autox.team.net/mailman/options/fot/fot-archive@autox.team.net
|