> I'm starting to get a picture of what I intend to do during the rebuild of
> my engine. I'm still undecided (or unsure) of a few points, and am
> interested in the list's opinion:
What was that Dave Massey said about opinions ? <g>
> -Compression ratio: The comp prep manual suggests 10.2:1 for a street
> engine. I'm going with a cam that is a step down from the "D" grind (270
> duration vs. 284, a bit less lift). Would a C/R around 10 be any problem
> with today's gas (I would run premium)?
I believe so, unless you also do a fair amount of combustion chamber work to
remove the hot spots (as also outlined in the comp prep manual). Note that
today's premium in the US is about the same octane as originally called for
with the stock C/R ... and it's likely to drop further.
> Can a C/R be too high for a given
> cam?
As far as I know, no. I'm no expert on cams though ...
> -Lightening: The comp prep manual shows where to shed quite a
> bit of weight
> from the rods. I won't be rev'ing over 5000 (not going to install the
> harmonic damper kit), is lightening the rods still beneficial? Same
> question for the rocker arms.
Might reward you with a little less wear and valve float at red line,
probably won't make much other difference.
> -Alloy sump: Seems like "everyone" used to carry these, now only
> Racetorations & BFE still seem to (for big $$). Anyone know of another
> source?
I don't.
> Chromoly pushrods: I'm probably going to get new pushrods. Are chromoly
> pushrods stronger or lighter than stock? Or both?
Stronger. Ken Gillanders (of BFE) once wrote of looking at stock 5/16"
pushrods with a strobe light, he said they looked like "dancing spaghetti".
> Header: I'm still undecided on using the stock TR4A manifold or a header.
> One issue is the heat. Do the ceramic coatings really work? I might do
> that even on the stock manifold. Does everyone supply the same
> headers, or
> is one better than the others?
There are several different headers around, with distinctive designs.
However the stock 4A 4-2-1 design supposedly works pretty good on the
street, and the best headers for the street supposedly mimic this design.
Randall
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