[screamingchief]

Anyone out there that thinks a low CR combo automatically = a complete slug has probably never driven a well tuned dead stock 455 H-O equipped GTO or T/A in their life.

They'll easily run with most any of the similarly equipped "dead stock" high compression GTO's or T/A's that were available back then.

Same wide LSA cams,along with the "same" most everything else for the most part,they just dropped the CR for the reduced fuel quality,the difference was like 25 "rated" hp between the '70 GTO 455 (360hp) and the '71 455 H-O GTO (335 hp),and honestly that was nothing that could'nt be recovered with just a little bit of careful tuning and such.

And as someone else commented on,with todays less than perfect fuels,one can often be much more aggressive with the timing curve on that low compression 455 H-O combo vs. the '70 455 high compression combo.

Honestly that '70 455 high compression ratio engine was severly undercammed by most hi-perf. folks standards.

The '70 455 high compression engine used the 067 & 068 cam based on trans (AT/MT)

The low compression 455 H-O also used the 068 cam.

Even the low compression 455 SD used the 744 cam.

So that '70 high compression 455 probably should've used the 041 cam w/1.5 rockers.

But then they would have had to really "fudge the numbers" to get it past GM corporate.

So ask me,it's more than just a wide LSA that dictates cam choice in any CR engine.

It's only when you start building beyond what the factory built,and specifically choosing and selecting a specific parts combo for maximum gains that you'll typically be able to exploit all of these different options & areas of potential gain to maximum effect as guys like Cliff R. talk about all the time.

And even then the results can vary somewhat on a case by case basis,like I said above the devil is definitely in the details,and not everyone gets all those details "just so" like others seem to be able to do with little to no effort.

Often it's a matter of weighing any potential gains against the effort involved in doing such that tends to make some guys approach their CR choices in a more conservative manner.

To many,a street car is'nt looking for every last .10 of ET or MPH.

Once that sorta dynamic becomes the primary driving force for a build,most folks would suggest that it is a race car that's pretending to be a street car.

To many a street car runs what it runs,it's more about having fun than running a number.

FWIW

Bret P.