Thread: Budget Chevy 355 Thoughts

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I put together 355 with stock 441 heads done up. Forged flat top pistons , comp xtreme 268 cam with roller tip rockers. Shaved heads and deck block. Aluminum 2701 dual plane with Holley 600 vacum secondary. Transmission 350with 373 gear. This should be decent combination for street. For another nova project.

You don't say how much you shaved the heads, but without the head shave, the compression ratio would have been 8.4:1 and the 268 cam would be a little much for the motor. It may be a little soggy on the bottom end compared to a little shorter cam. On the flip side, you probably didn't set the squish at 0.035" to 0.040", so the bleed-off of the longer cam won't allow the motor to build cylinder pressure to the point where you might worry about detonation either.

I have used this combo many times for F bodies . It works well. I dgreed the cam forward 4deg for chain break in. After checking chain stretch when customers have requested it, I found the cams were always within a half of a degree of where manufacturer recommended. Mind you these were built for decent running setups with out spending big bucks. Everyone was pleased and started getting a bit more greedy for other options in the drivetrain etc (figures...lol) I have used same combo with varying cams but always kept it moderate,272 crane, 260 and 268 comp,even dug out some old school isky and ersons. I like what he's doing here with this thing.

I am not a big fan of symetrical grinds in a small block Chevy un-less your exhaust to intake ratio is over 75%.
This cam will work but the XE 256 would work better.The specs. are .447/.454,duration at .050 is 212/218 on a 110 l/s.
Also a looser stall would help out a bunch say around 2,000 rpm's.