piston to valve clearence

[red86chevy]

I'm going to check this in a couple of days using the clay method but was wondering if you guys think I'll have a problem.

383 with eagle flat top piston with -7cc valve reliefs. also using a comp 286h cam (.490) lift with 236 degese of duration @ .050 lift. It is 4 degrese advanced.

Also using a gm .028" head gasket. The block is not decked.

Any opinions?

Jeremy

[87 STEPPER]

Haven't a clue!

You should post this in the Engine forum you will probably get a better responce there.

What did your machine shop guy say he could probably tell you if there will be a clearance isseu.

Good luck.

[BADGMC]

I don't see that cam being an issue with what you have. I run a comp 274 extreme solid which is actually a lot more aggressive than the 286H and there is plenty of room. I would do the clay check just for the sake of doing it though. There is no such thing as checking clearances too much. Also, if you don't mind could you share some info on your 383 you are building. It bothers me when someone spends lots of money on a "wicked" combination and then they are baffled by it when it only goes a couple of tenths quicker than their old stuff. Many people on here have a lot of real world tips which can help a lot.

[red86chevy]

My 383 specs are as follows

1980 350 4 bolt block
.030 over
sportsman II heads with 2.02 valves and 64cc combustion chambers
Eagle 383 kit (Flat top clamer pistons with -7cc valve reliefs, reconditioned rods with arp bolts, speed pro rings, Clevite bearings, cast steel crank, balancer, and flexplate)

comp 286h cam
edlebrock dual plane performer rpm intake
holley 600 soon to be a 670

Jeremy

[BADGMC]

That should be pretty close. I used an eagle rotating assembly also except mine had dish pistons which put it at about 8.5:1 compression. You should be closer to 10. One thing I would think about is the cam. Big cams in heavy vehicles don't get along and a 286 is pushing it unless you run like 13 to 1 compression to cover it up. Just for an example my truck without the blower ran mid to high 13's with the 274XS comp cam. A friend of mine has a shortbox with an 12 to 1 355 and a comp XE294 and that only runs high 13's. There is also a big drivability difference between the two. Anyways good luck I think it should work out for you.