A couple years ago, I saw a flow bench test for a STOCK 235 head, for a stroker build to 255". At valve lifts over .450", there seemed to be a lot of unwanted turbulence around the valve if I recall. Most of the 235 cams I've seen offered are in the .400-.425" range - advertised lift with 1.5 stock rockers. In reality, the rockers seem to measure LESS - more like 1.4-1.45:1, from what I've read here on the board.Knowing this, I wouldn't try for more than .460 to .480 MAX, on a NEW BLANK. I don't think a regrind could safely get into that range, but is nearly HALF the cost of a NEW cam!
In 1978, I bought a RV cam from Clifford, ground by Sig Earson. Ether they filled out the cam card WRONG, or they used a 250 pattern on my 235 stick - adv. duration and lift was 264-.480"! I used stock springs, push rods,retainers with no issues - driving the PISS out of that mill as a dumb,heavy-footed ute in my 20's, driving all over hell in my '53 p/u - IT RAN GOOD!!!
I've been intrigued by DUAL PATTERN cams, ever since learning about Mcguirk using them back in the '50's. I asked Isky if he still has Frank's cam masters - he did, and remembered helping him develop those cams, as they were very close friends! I mention this, as SCHNEIDER offers dual-pattern grinds for the later Chevy sixes - I'm thinking about calling Jerry Cantrell about using one for my 261 build on a stock core, for my '57 car. Adding duration on the exhaust side has got to help those BAD ports breath a little better!
MAN, what a great thread this is... GREAT JOB GUYS!!!
- Tim
