[Amc-list] 195.6 with a turbo

[Tom Jennings <tomj@xxxxxxx>]

OK got my turbo sim software, quite nice! It even has the AMC
195.6 OHV motor in it's list of stock engines! In the same list
as 2-valve Honda motors and all that!

Question: Anyone know the exhaust cam timing? Oddly, intake
specs are in the TSM, but exhaust isn't.

With fudged cam specs, the software's HP and torque curve shape
look right, as are the numbers. I realize the numbers are not
to be "beleived", and I don't care about them; it's the shape
of curves that matters.



"On paper" stock HP peaks aroudn 4000 rpm (software says 108),
but the torque curve is nearly flat from 1500 - 3500, which
is about correct. Most of AMCs sixes are cammed like this --
flat torque.

There are a number of modern turbos that are just right. The
motor wants a low A/R, since this isn't a typical turbo job
looking for max. HP at high revs, but a leap in torque across
a low, broad range.

Stock torque TSM says 180 ft/lbs; the software says 166. Good
enough.

With a little turbo, 1.6" compressor, .35 A/R, at a mere 4
lbs of boost, the torque jumps from 166 to 200+ ft/lbs, 1500
rpm to 3500. That's 25% more torque, a no-brainer, won't tax
cooling system or a T-96, and would cross the threshold into
all round drivability.

At 8 lbs boost, torque goes to > 250 ft/lbs 1500 - 3000 rpm, >
200 at 4000 rpm. Peak HP is "only" 150 at 4000 rpm, but that's
about 60% increase in torque over a broad range!  That's not
really pushing things in the motor, though it will stress a
T-96. Any T-4, T-5 should be happy.

At 14 lbs boost, torque peaks at 300 ft/lbs, HP at 198. Likely
this is too much stress all around for a stock motor and
chassis. The HP numbers are unimprssive, but 300 ft/lbs of
torque in this car? Crap, the car would twist longitudinally
at green lights.


I was happy that this all matched my home-made spreadsheet,
which I made from formulas I found at Garrett's website. But
the sim software does graphs at all RPMs and all that nice stuff.


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