>BTW, have any of you Rod Length Theorists seen the article in the >January
5.0 Mustang Mag by Peterson Pubs. 11:1 compression with
>87 octane gas.
If you are interested in pursuing a long rod 302, set your browser
to http://www.geocities.com/Baja/Trails/1630/trx/trx-4.htm. There
you'll see pictures of the 11:1 compression long rod 302 that Dave
Williams is building for his 1st generation Mazda 302. The build
up uses modified off-the-shelf parts, including 5.56" Chevy 400
small block rods (1/2 longer than stock 302 rods) and Keith Black
hypereutectic pistons (1.14" pin height for a 6" rod 383 Chevy
stroker). If you return to his home page, you'll also find links
to other interesting stuff including a how-to article on 347 and
355 cubic inch 302 strokers, and pictures of Dave's balancing of
a 366 cubic inch 289 stroker crank.
Since the RX7 weighs very close to a Tiger, it will be interesting
to see how the engine performs in Dave's RX7. In general, long
rods are a good thing to do but they are only one component of
overall engine system. Like anything else, they need to be matched
to the rest of the components to maximize the benefit. I've recently
acquired a copy of Dynomation's engine simulation program (a high
fidelity simulation, not one of those $99 calibrated guessing routines)
and it will be interesting to see how juggling various variables, like
rod length, affect an engine's output.
One of the things I've seen the magazine articles claim, that I don't
believe, is that longer rods allow higher compression ratios. That
doesn't make intuitive sense. Since the piston is dwelling around
top dead center longer (arrives earlier), I would expect long rod
engines would be less tolerant of high compression.
Later,
Dan Jones
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