We built the HO and SD on my side of town for the article, Dan and I live 120 miles apart, so they tend to be his side or myside builds. The RA III/IV and 350 HO comparo's we each took care of one motor apiece. When we lost the cam lobe in my HO Scott Tieman had my car as he usually races it. Dan then did it on his side of town. We will be doing an article in Pontiac Enthusiast on the updated build when I get off my butt and write it.
To answer the compression ration issue. On '71 motors you can take your heads from the factory stated 111cc's down to 98cc's. You can use a .000 deck in combination with 3.1cc pistons. A gasket thickness of .030 which we find to not produce enough squish. When all is said and done if you ran a +.070 bore w/a legal +.0015 off set grind on the crank you get just shy of 10:1. It is 9.9+ actually.
The cam is the one I developed with endless hours of dyno time and input from Dan along the way. It has evovled with each build and dyno session. It is now very well refined. We have refined it not just in HO's but in RA III's and HO 400's. It is now in it's fifth generation.
We follow all the rules very religously. The .050 duration is 212/225 just like the factory 068. It has the near the maximum allowable lift of .424 on each side with 1.5 rockers. Pontiac factory tolerance allowed +/- .011 on lift. If you take the intended lift of .413 that Pontiac spec'd that is how the NHRA rules hit .424. It is also the tolerances that Pontiac turned in to the AMA in '71.
This cam has taken us from a Melling 068 dyno run on the first HO of 370 hp to our now 403 hp level. Along with other changes mind you. The cam can account for 15+ of that change. It really is a just a well blueprinted version of the original. Like all the PS motor build ups it is careful attention to the detials that pays off.
RA III's have shown even better progress. We took the melling base line 068 also at 370 hp for a RA III. The 1st gen cam used in my brothers '69 T/A made 387 hp. The third gen version had a '67 HO 400 making 412 hp and now the latest gen has similarly built RA III's capable of making 420+!
For RA IV's we have found the factory cam to be simply amazing. We have tried many different brands and options but the Melling replacement is
almostperfect.
To date we have only given cams to customers who are having Dan or I do the motors as we really are not in the cam business nor want to be. For internal tracking of which generation we are at we now call it our JW Racing 068M cam.
I also developed correct valve relief cc'd pistons for this application and those are the pistons that are used in all the HO's discussed in these postings that Dan or I have done.
I would recommend Dan to anyone. He is limited as I am to how many of these we can do (hence why Dan handles some of my personal motors). He is extremely careful and particular about his motor builds. I simply can not express enough how good he is.
I hope this is helping everyone because I am becoming very self concious with all this talk about ME ME ME. I just feel it is in the best interest of all us die hard Pontiac guys to have our cars out there making the most possible and putting it to all those brand X cars
Mark