Hi William,
Your point is well taken.
One of the 6pack experts pointed me to some of his friends to help me
with the engine rebuild. One owns an automobile repair shop and they
both race. They are going to build my engine for me, and have access to
an excellent machine shop. They have offered to do most of the work on
it while I'm there, so I can watch and learn.
I'm the original owner of my TR250. It has 60K miles, and it's special
to me, so I want it done right. I have a couple of MGB's, so I'll do
them myself next.
This is my first engine rebuild since putting a 289 4 speed in my 60
Ford Falcon station wagon back in '69, so I am quite clueless. I hold
the 6pack record for asking the most dumb questions. :-) When I started
a couple of months ago I thought a Rod Journal was the diary of a now
deceased actor -- not really but close. :-)
I have read everything in sight written my David Vizard, Kastner, Roger
Williams, etc. and with the help of the folks on this message board I
think I have come a long way.
Many of my questions have to do with trying to distinguish between what
is practical for my intended use of the car, and what is best left to
the racers. It's not always clear, so I ask. The valve angle is an
example. Vizard recommends it for the BMC "A" series engine, and he
seems to be talking in general for all engines. He usually makes it
clear when he is talking about engines in general vs the "A" series --
but not always. The experts on this board have recommend Vizards "A"
series book to me because much of it applies to all engines.
Vizard recommends back cutting the valves in his Triumph 2500 engine
tuning manual, but does not mention the 30 degree valve cut. His Triumph
tuning book was written in 1970, and the "A" series manual was last
updated in 1999, so maybe things have changed. Seems to me back cutting
and the 30 degree angle are steps along the same path. I believe that is
true of most head work. A lot of little things add up to something
significant. Any one alone, out of context of the others, could be
pointless. Kastner does not mention the 30 degree valve angle -- again
written in 1969. Others on the 6pack list have recommended it.
But you make a good point. I'm not going to race, so if I can't feel it
at the stop light, why bother... But I have to understand before I can
decide, so I read the books, the 6pack list, and ask. By the time I'm
done, who knows, maybe I'll be able to help the next guy.
Thanks for the post. I appreciate it.
Don
William Whitmoyer wrote:
>
> Don:
>
> Please see my other recent post about my jumping between conjecture about
> valve-seat-grind-angle vs. facts about valve-angle-to-the-head to
> illustrate the point that there is no one right answer in my original
> message....but more to your question below. Pro Stock V8s have custom
> cylinder heads, and, as such, during design/manufacture they can dictate
> many things, such as valve-angle-to-the-head, that you couldn't change
> while rebuilding a regular production motor. Although that's not something
> that directly applies to our TR6s, I think it's reasonable to
> assume...oh....well...forget it....I'm just going to go home and work on my
> Fiat Spider now.
>
> Date: Sat, 07 Dec 2002 18:45:30 -0500
> From: Don Malling <dmallin@attglobal.net>
> Subject: Re: Fwd: RE: 30 degree valve seats and 3 angle valve grid
> Hi Tim,
> Yes you are correct. I reread Williams note and I believe he is talking
> about the angle of the valve stem. I haven't a clue as to how to go
> about changing that.
> ----------cut------------------------
>
> William Whitmoyer
> 69 TR6
> 72 Fiat Spider
> 90 BMW iX
> 91 CRX Si
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