Hello,
I am building a /6 powered Rat Rod and would like some help in cam selection. Being a Rat Rod, I'm not really interested in all out performance--just ground pounding sound and ease on valvetrain. Kinda like the Comp Cams Thumper grinds. I'm running one of those in my other rod and sounds real good. I have 10.0 compression, oversize valves, mild porting, Hurricane 4bbl intake, Holley 570 Street Avenger carb, shortie headers, Automatic transmission--stall dependant on cam selection and a 3.54 gear. Target weight for the car is approx 2500#. Any help or advice will be greatly appreciated.
Thanks in advance--BERT

I wish I could talk you out of the Holley Street Avenger. Too much carb for a 225 and one of Holley's less successful designs. The emulsion characteristics of that carb are pretty goofy. I'd do a 500 Edelbrock AVS.

For the cam if you're willing to buy a 2800+ RPM stall converter I'd use Oregon Cam Grinding #346 or the 280/270 Erson.

http://slantsix.org/forum/viewtopic.php?p=218596

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Joshua

OK--The 570 is not set in stone. I have one my other and it works good, but it is a V-8. How does the Oregon 346 grind sound?
Thanks--Bert

A lot of old mechanical cam grinds have significant valve train noise. The Oregon 346 has a pretty tight lash setting so I would expect it to run a bit quieter than most cams with similar lift and duration numbers. If your compression ratio really is 10:1 it should idle reasonably well, but have a serious exhaust note with a performance muffler. Degree the cam with a 100-102° intake centerline. What makes exhaust noise is residual cylinder pressure when the exhaust valve opens and the exhaust system itself. I haven't run this particular grind myself. I bought a #791 as I wanted more exhaust duration to compliment a nitrous system. I still don't have that engine in the car though.

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Joshua