Expert: Dan Liddy - 2/17/2005

Question
I'm building a race motor with Rods .800" longer than standard.  The stroke remains the same.  The new center to center legnth is 7.050".  The new ratio is 1.99:1.  The point is to maximize torque.  So, How what do I tell the camshaft grinder to do?  Currently, stock rodded race motors do well with .550 lift, 328d and LCA of about 108... How do I modify the cam lobes to take advantage of the new legnthened T.D.C. dwell time?

Answer
Hi Mordy:
Thanks for an interesting question. If being a volunteer on All Experts has taught me one thing, it's how much I DON'T  know !

I think in this case, that the extended TDC dwell time might allow you to use a shade less intake advance.  Though it might affect the fuel mixture, it will also reduce the amount of exhaust reversion. A big plus.

Yours is a question I would present to the cam grinder, and I mean the big kahuna, that runs the shop.  Then I would present the same question to 2 or 3 other cam shops, and compare their answers.  Make your decisions based upon what they tell you, and use the experience to judge which cam grinder is the guy you trust with such things.

The guy I use is a wizard, and did a lot of work for Bob Sharpe Racing  (that's Scott Sharpe's dad)  and ground most of the cams that Paul Newman used during his several Trans Am Championship efforts.  He is my wellspring of info when it comes to those kinds of problems.

If you'd care to consult with him, his company is Cam Techniques, phone is (941) 727 5552 in Bradenton Florida, and he also does a lot of drag race and stock car stuff.  


Good luck with your project.

Dan Liddy
Sarasota, Florida