Scott,
I vote for having an "expert" do it. The only reason I say this is because
without a flowbench you're really just guessing what is best...It is PROBABLY
better than stock, but that doesn't mean you aren't hurting flow or not
getting the best out of it. Also if that person is experience doing the
specific type of head he knows how much can be taken off where and safetly do
it.
But I also vote for doing it yourself. If getting the absolute maximum
horsepower out of the engine isn't the goal then you should be able to do a
good job of porting if you follow the Kastner book guidelines.
As to milling the head or the block...There are several opinions out
there...all good and all have theories. I like to take about .015" off the
block of the "recessed groove" type blocks when going above 10:1 compression.
The head gaskets always seem to seal better. I know some like to leave the
head as thick as possible for cooling purposes. I know some who like to mill
a bunch from the head and pop the pistons up...My guess...it's going to be
cheaper to mill the head...
aaron
--
All the best
Aaron Johnson
#38 FP Spitfire Mk4 Southern Illinois Region SCCA
http://www.geocities.com/spitracer9
> I'm building up a new engine for my vintage race GT6 MkII. Any comments on
> improving the porting on my own, versus having someone with more experience
> and/or a flow bench do it? I've read through Kas' guidelines, have the air
> tools, and in fact did this years ago on a motorcycle, but that doesn't make
> me an expert.
>
> Also, should I be planning to mill the head or block to increase
> compression? Planning on using flat top Venolia pistons.
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