Quote:
Originally Posted by 71 Ventura II
Automatic transmission I'd expect to see in the neighborhood of 286 HP to 296 HP at the rear wheels. If your at a fairly high altitude then 275 RWHP is all you can expect. JD
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Quote:
Originally Posted by Cliff R
With unported heads on a zero deck shortblock we've made 419hp/453tq at the flywheel.
We've got customers running mid to high 12's in street driven FB's and GTO's with that combo, so the track numbers support what we saw on the dyno.
Something fundamentally wrong someplace? Even at 9 to 1 compression it should make more HP than what you are seeing. Torque may be down some do to the lower compression, but I'd still expect 380-400hp/420-430tq at the flywheel with that cam in a 400 engine with 9 to 1 compression.
One negative I've seen with that cam, without exception every single one has needed to be advanced at least 4 degrees, some more than that, to get them down to 108-109ICL......Cliff
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Quote:
Originally Posted by chiphead
According to the CP website, 91CC on a zero deck shortblock is 9.3 compression. That's about what I have, with 70CC heads and 20CC dished pistons.
If you don't degree the cam with a degree kit, you don't really know where you are. +4 on the timing chain gear isn't always really +4. You can still be way off in the weeds with cam timing.
What are your ignition timing settings? What carb, intake, etc?
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Hello guys, remember "He's" reporting +- 275
RWHP not crankshaft! 275 RWHP is equal to +- 357 HP at the crank when running a traditional 3 speed automatic. A full point of compression equals +- 8% difference in HP. So, for you guys who found +- 405-419HP at the crank running @10.0-1 compression in a similar combo try the math. Drop the power by the 8% accounting for the drop to 9.0-1 compression you get, 372-385 HP at the crank or expected +- 286.44-296.45
RWHP .
Accounting for the 8% loss due to compression drop the 372-385 will yield a RWHP of 286.44-296.45 as stated. That's only 3-7% below expected return, Not a fundamental issue, more like a fine tuning reward.
Factors in play effecting results: Lower compression and driveline parasitic loss. He's not far from expectation for the combination of parts in the environment. He lives only 627' above sea level which is cool! JD
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Good luck to the new owner of the Ventura II! Sold the car after 13+ years. Look for it on the Hot Rod Power Tour in the future as it's currently being re-configured as a Pro-Touring ride!
