Rear wheel dyno # + correction for old engines of big 3

[69gt4speed]

Well us older guys sit around and talk how fast old cars were. I ran across some rwhp corrected numbers for some old engines from the big 3.... Now I cannot find what "street" 427 for the ford means... Anyways here are the engines and numbers... Compare to new engines. This is corrected by +18% for the quoted figures for the "flywheel numbers" listed..
I don't know the exhaust system setups etc.

Better late than never................
Disclaimer:All HP and TQ figures based on actual rear wheel results +18%
for drivetrain losses

Stock, 24,400 mile original 1970 428CJ Mach I (rated 335 hp)
(actual dyno numbers as performed 6/06/05)
367hp 394ft/lbs of torque

Stock 3,672 mile 427 "street" cobra w/1-4V (rated 425 hp)
(actual dyno numbers as performed 6/06/05)
399hp 467ft/lbs of torque

Stock 22,200 mile original 1967 427 Corvette 1-4V (rated 425hp)
(actual dyno numbers as performed 6/06/05)
401hp 422ft/lbs of torque

Stock 2,400 mile original Hemi Cuda (Rated 425 hp)
(actual dyno numbers as performed 6/06/05)
418hp 451ft/lbs of torque

This would be on an 05 Dynoject with all of the bells and whistles.
Two of the cars had their own printouts from a Mustang unit, and both
were compared......Less than a 2% difference, one that I chalk up to
different temp and humidity (and altitude) from the days we made our
pulls

[DustinsDuster]

and those numbers are at the wheels? pretty damn impressive...

[69gt4speed]

Those numbers are to the wheels plus 18% to make it flywheel numbers.... So those numbers are flywheel numbers.... assuming a 18% loss through the driveline... So that means mid 300's to low 300 rwhp for most any street big block back in the day. All those engines used flat tappet cams and non ported iron heads. We ought to get something for 40+ yrs.

[stangvortech]

Wow, that is very interesting with the mach....

[69gt4speed]

They underrated those cj when they came out in 68.5 for nhra stock and s/s and insurance. Everybody caught on by 69. I know about the insurance on a 69. A police version was rated 365 hp only thing different it had a alum version of the intake.

[69gt4speed]

A update of sorts, numbers matching 428scj on engine dyno. Scj meant upgraded modified lemans rods and aux balancer otherwise same old stuff. Hdy 491 lift 194/204 dur cam, cast iron intake and exhaust, 735 holley. Rated same as a cj at 335 hp 440 tq.
http://www.youtube.com/watch?v=g75YwO_Wdzo