Originally Posted by chevymastermind
I have a set of Chevy heads with a casting number of 333882, with 1.94 Heads, i am hoping to make 350-375HP with them. the engine is a 350 Steel crank, 4 bolt main, 9.5:1 compression ratio with these heads, comp cams .480/.480 lift with 230/230 Duration at 0.50, 600cfm edelbrock carb, Performer RPM intake, headers with Flowmaster 40 series mufflers dumped befor rear end, and 1.5 ratio roller rockers. i just want to know if these heads will be good for my engine before i pay to have P.E.D. Rebuild the for $450?
also give me your general opinion of these heads.
882s are a SMOG era cross over head. They have a large, open chamber. Early production 74/75 may or may not have hardened seats depending on whether the heads came off a passenger car or a truck. By 76 all were getting induction hardened seats. It only takes trying to shoot the exhaust seats or port in the port to see which. Hardened seats eat stones very fast or cut slowly on a Serdi compared to non-hardened seats, so theyíre easy to identify.
The 882 has some serious short comings with its chamber shape. These are an open chamber of 74-76, or more likely 78, CCs with the sparkplug way off on the far side of the chamber. They are an excellent low NOx emission chamber but not good at much of anything else, except if youíre running a little super charge or some nitrous. Then the extra volume helps get the larger quantities of mixture into the engine. But for running on atmospheric air pressure and gasoline, they are not the best solution. Though you can get 350 to 375 horses naturally aspirated with them but it takes a flat top piston and more cam shaft to do it.
If you figure one of these heads with flat tops having 7ccs of valve relief in the piston, in a zero decked block thatís thirty over with a .041 head gasket, the compression ratio will be about 9.1, which is probably a pretty good CR for these heads. Knowing what little I do, I'd say your 9.5 is optimistic. But to get the power up will take a good cam around the equivalent of 275 to 280 degrees. This dumps the low and mid range DCR making a balky, fuel hungry engine under 3000 RPM. Not as big a problem if you gear up for it, though the engine will stay hungry just for a different reason. But this much cam drives you to a higher stall converter and even more fuel burn. So you just start down a road of issues and problems that Vortec type heads simply solve. Besides by the time you pump the cash into the 882ís you can be looking at new technology Vortecs.
The Vortec ports flow super good out of the box, way ahead of the 882s on their best ported day. Add to that the efficiency of the tight chamber with a centrally located sparkplug it turns getting to 350-375 hp into a no brainer. Plus this can be done with a lot less cam, say a comp 256 or 262. This reduces the low RPM reverse pumping which leads to higher gearing and less of a hole in wallet at the gas pump. A comp 256 or 262 wonít require grinding on the top of the guides or a high stall converter. In addition you donít have to throw over rich mixtures that wash the oil off the cylinder walls shortening engine life. The aftermarket sells vortec type heads that will allow you to use your existing intake so your not limited to GMPP. Just go shopping over at Dart or World, and bunch of others domestic and foreign and see what they have. There is some powerful stuff out there.
So for few dollars more than rebuilding the 882ís you can get a much friendlier engine that has a real back bite if you choose to use it.