So tuning on the exhaust is more important than the
back pressure. I have room for about 26 inch primaries on the exh. without
gymnastics. Over that length, I have to get creative and things start to look
like a bunch of stainless entrails.
The intake port 1 7/8 dia? or
smaller?
I've been toying with the Idea of mechanical
injection and an MSD ignition on the leading plugs with magneto trailing. Have
yet to decide over EFI.
On the redrive ratio. The prop becomes a problem
for speeds at and over 250 mph with the 2.87. The inner part of the prop disc,
even with a 16in spinner becomes pure drag at that speed. I am also trying to
keep the nose from being too high in the air on a relatively short tail dragger.
The ideal set up would be a 2.5 reduction ratio and a 68 in variable pitch
prop for my particular application. 2.17 is the closest I can get in a proven
gear set. The GM TH350 first planet is 2.5 but it is a screw ball set up
and short of a $1000+ billet drag racer special, is not available in a 6
pinion planet carrier. So it is a compromise. Give up a little in climb and
take-off for top speed and cruise. With power to burn this is not an issue.
If it is a CS prop will fix it. In my opinion a CS prop will do more for
performance than a turbo ever will. Besides to make a turbo work right you
really need a CS prop. ED what's up with that thing, has our spook abandoned
us???
Monty
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