[Scott Roberts]

Originally Posted by Tom Vaught

I WOULD TOTALLY DISAGREE WITH THAT SENTENCE.

I was fortunate to have access to a Clayton Rear Wheel Dynometer at the college down the road from where I lived.
They had a Automotive program there. A/C work, Engine work, Chassis work, some welding classes, etc.

On the Calibrated Clayton Dynometer several vehicles that the Hot Rod Boys owned were tested.

1) A 375 hp advertised 396 1966 Chevelle made 285 rear wheel hp.
285 hp times 1.15 = 327 engine horsepower. the 15% adder is the typical drop from engine to tire hp loss.
The 375 HP rating was probably correct if you tested the engine without the water pump/fan drag and the accessory drag.
(Power steering). Looks Dead Nuts on the money to me.

Tom V.

I dont claim to be an expert and have no problem with your disagreement... as state, I was under the understanding that was the case.... I've read ( interweb facts of course) that was the case...
I drove a bonestock 68 bird with a 400 and It sure felt like more than 330ish... seat of the pants kind of thing..

[Steve C.]

Questions and Answers – Horsepower

https://www.stevelinden.com/blog/que...ers-horsepower


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[TCSGTO]

Either the RAIV was under rated or the RAIII was overrated sine there is no way only 4 HP separated the two.
I remember an old Roger Huntington article where he had the factory dyno curves for some 60's hipo engines. If they wanted to rate conservatively they pull the HP from below peak. For instance the 426 HEMI was rated at 425Hp @ 5000 rpm when it actually peaked closer to 6000 and 470HP.
Factory advertised ratings were just that, advertised.

[Scott Roberts]

Originally Posted by TCSGTO

Either the RAIV was under rated or the RAIII was overrated sine there is no way only 4 HP separated the two.
I remember an old Roger Huntington article where he had the factory dyno curves for some 60's hipo engines. If they wanted to rate conservatively they pull the HP from below peak. For instance the 426 HEMI was rated at 425Hp @ 5000 rpm when it actually peaked closer to 6000 and 470HP.
Factory advertised ratings were just that, advertised.

Same stuff I read... so who's right, Tom or the internet... the internet if full of underrated stories but Tom says thats false... in all caps. I'm going with motor city tom...what could those other guys possibly know.