>
>Tony-
>Been busier than a one-legged man in an a*s kickin contest lately
>and haven't had a chance to say hi. Seems all I do is work,work,
>work and there's always more...
>Sounds like you are gettin way ahead of me on the TR6 implant
>motor. Since you are doing all the neat stuff, I hope you are either
>touching up the combustion chambers or having someone do it
>for you. It would be a shame to do all that work and not at least unshroud
>the valves. If you have a grinder it is not that hard to do.
>If you have never done this before, just take the edges off of the
>ledges created on both sides of the chamber when they bored the area where
>the valve sits. The edges in question are located either side of the spark
>plug hole and directly across on the opposite side of the chamber. These can
>actually be ground flat to the existing chamber wall, but it gets a little
>scary if you have not ported heads before, so just round off the sharp edge
>of each of
>the four ledges in each chamber. It will make a much nicer flow pattern and
>often reduce the chance of run on.
>In your last note, you talked about filling up a hole in the intake manifold.
>I hope that you are not talking about the transfer tube hole. (The hole at
>either end of the tube connecting the manifold together) This tube, if
>anything, should be as big as possible. It
>helps keep the reversion pulses down and keeps a smoother flow through each
>carb, resulting in a better fuel dispersion. Without this tube there would be
>fuel standoff and lean condition at low to mid revs.
>Keep us all posted on your progress, especially me, as we both don't need to
>make the same mistakes <g>
>
> Yours in Grease
> Nick
>
>
Nick,
Did that, didn't know it was called "unshrouding" It's an old Hot
Rodders trick to flatten out the inside of the head to allow the
combustion to expand in an undistorted chamber.
What I was referring to when I said filled in the spaces in the intake
manifold was the gas between the two halves of a casting.
Right inside the intake about is two "V" shaped mixture directing vanes
for each carb, which directs the air/fuel mixture to each of the cylinders.
Since a manifold is cast effectively as two pieces in the aluminum
version, each "V" shaped directing vane has a small space in the middle,
which is an inherent design flaw along with all og the flash material
on the inside of the intake ports.
I ran out to the machine shop and had them hit each vane with the
heli-arc then I came home and finished polishing the intake ports with a
flexible grinding cable on an old sewing machine motor (my own creation).
The shaft is long enough that I was able to clean each intake port of all
the garbage.
Fuel will flow better without having to find its way over humps and bumps
on its way to the cylinders. At least that's how it's supposed to work.
The end result may be negligible, but I like to feel that I have done
everything possible to squeeze everything I can out of a motor.
As for progress on the conversion, I'm affraid I have hit atemporary snag.
I had to choose between buying back the 67 GT6 and finishing the engine.
Well, you can guess what I opted for. The engine is going to have to wait
a month or so for its new cam and pistons. The boring and head work are done,
but the rest has to wait.
You may beat me to it afterall.
Slow down and smell the flowers along the way. All work and no play
makes Nick a dull boy.
Best Regards,
Tony
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