At 08:41 PM 6/7/2002 -0700, you wrote:
>I'm sorry, but NO these ratings aren't SAE GROSS
>numbers. They're SAE NET,
Chad, I am not sure about that particular engine. I guess its
possible. One of the things I learnt though is that these after-market
manufacturers very-very often have over-boosted claims. Is this one of
these "typical" cases? I do not know. I can tell you one thing
though. In order to get so much power out of a relatively small engine
(without supercharging or benefits of a modern tuned manifold) there is
only one way: Bigger cam to increase the operating power range, at the
expense of driveability, durability, and fuel economy. Also, a rule of
thumb estimating the necessary increase in operating rpm is the
following. Say the stock carb high compression 360 has a net peak power of
220 hp at 4000 rpm. Given that the stock engine has fairly descent
head/manifold design with a volumetric efficiency of 85-90% at its peak
power, there is little improvement you can achieve on its peak torque. So,
by maintaining peak torque and raising the rpm range (bigger cam, bigger
valves, etc), in order to raise the power from 220 to 380, the peak power
rpm would have to increase roughly to (380/220)*4,000= 6900 rpm. Such an
engine would be useless below 3500-4000 rpm. For a 300 hp rating, the peak
power rpm would be 5450 rpm. Such an engine would be worthless below, say
2500-3000 rpm. Again, this is based on rough estimates.
> Another option might be to check into an engine out of a wrecked 5.9L
>(360)R/T Dakota. That engine is rated at 250 hp,
OK, there you go. Consider this. This fuel injected engine with
volumetric efficiency of probably over 100% due to its modern intake
manifold produces 250 hp net. I am sure this engine has a relatively small
cam, but its peak torque is potentially higher than a carb engine due to
manifold tuning. Are you sure that 380 hp of the low-tech crate
engine? Its possible, but I am not sure how likely... By the way, I
agree, this will be an excellent engine for an 81-83. If you get the stock
Dakota computer (I think you will have to) you will beat the 83
emissions. You will still benefit out of the lower gears, say 3.23.
D^2
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