I'm building a 355 small block chevy for drag racing only (no street use). I called three different cam mfgrs. for recomendations and the selections vary a bit. The car weighs 2300 lbs, 12 to 1 compression, Ported big valve 461 heads, 4000 to 4400 stall converter, turbo 400 4.56 gears, shifting at 6500 rpms. Take a look at what they recomend and let me know what you think.
Mfgr. Dur@.050 Lift Lobe sep RPM range

Crane 242-250 580-600 106 3500-7000
Lunati 254-259 622-618 106 4000-7000
Comp. 260-264 660-630 106 4000-7000
Any and all sugestions welcome. Thanks

 

I would go with the Lunati or the Comp. The Crane seems too small to me. I am running a Cam Motion 242/242@.050 with .581/.594 lift. I am considering stepping up a couple of sizes for my combo. This cam idles like a very small hydraulic cam. I have a feeling that if you go with the Comp, you will need to shift higher than 6500, though. I shift mine at about 6500-6600 rpm and its a 383. With the big stall you have, I probably would pick the Lunati. It seems to fit with your goals.

 

This 355 presently has a cast crank so thats why I'm limited to a shift point of 6500. In the past I,ve noticed that some cam mfgs. recomendations are more radical than others. Any other input out there?

 

I don't use cast cranks. If your going to spend all this money for 12 c/r balancing and solid roller can. Why would you take a chance on throwing it all in the dumpster. I've had to throw nice motors in the dumpster, but I did everything I could with the amount of money I had to make them last.

If you want a 355 to go fast your going to have to spin lots of rpm. Or you can build a stroker motor and go just as fast with something that will last longer because of less rpm to make the same amount of power.

When your building a motor the higher the compression the bigger the bang. They are just hard on barrings and rods. If your going to make a race car why stop at 12 c/r I have ran 13.8 and 15 to one 355's

Out of the above cam I would go with the crane. Much more lift than that you have to start thinking about .100 longer valve stems and retainers to set the installed height above 1.900. Even ported with 2.055 /1.6 valves your heads have flow limitations do to the small cc of the ports. things have come a long way in 30 years. Any cam this size is going to require big dual springs in the 190 lbs class 1.46 or 1.55 dia with 7/16 screw in studs and stud girdle

 

What kind of intake are you running?

 

Victor Jr.