"Graziano, Michael" wrote:
> 1. From the John Twist article and list member suggestions "draw out the
> oil pump shaft housing and increase the diameter of the center oil gallery
> from 1/4 inch to 5/16 inch (doubling the cross sectional area, hence
> doubling the oil available). "
>
> Can this be done without having to dismantle the entire engine? I'd like
> to do this as the engine oil pressure can get REALLY low in the summer when
> it's hot, but I also don't have an endless supply of cash.
Your low oil pressure problem is almost assuredly wear, which this will not
address. If you really want to fix the oil pressure problem, tear the engine
down, and at least replace the bearings.
> 2. Also, port and shave the head. I've been reading the "Theory and
> Practice Of Cylinder Head Modification" by Vizard. I'm not very far yet,
> but with almost two hours of commuting time a day, I'll have read a lot
> (maybe the whole thing) within a few weeks. How difficult is this? Vizard
> makes it seem that anyone with a brain, and a few tools (like a dremel w/
> flex shaft) can port and polish a head. Is this a realistic approach for me
> to take? Can it be done by a shade tree mechanic?
It takes no great skill to operate a grinder. Removing metal isn't difficult.
Removing metal in a way that doesn't destroy the head and improves air flow,
that's a horse of a different color. To do that, you need a flow bench, and
several heads to destroy as you learn. You can make a flow bench easily
enough. And you can destroy heads easily enough experimenting. Will you have
learned enough to actually improve the flow and performance of the engine?
Honestly, doubtfull.
Not only is porting and polishing tuned for specific applications, it's specific
to the engine. As in where are the water passages, what are actual
restrictions, etc. You are best served by having a shop that is experienced in
your specific engine do the work. They are the most likely to get you good
results, without destroying your head. Off hand, I'd suggest you contact
Paeco. They are expensive, but they seem to be very good, and quite experienced
with Spitfires.
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