I've currently got 64cc size combustion chamber heads on my 350, would I get any benfit by going up to say 882 heads with a 76cc size combustion chamber? I'm just wondering cause I'm blowing major smoke from my PCV valve and figure a rebuild is in order soon.

Thanks

the size of the combustion chamber ultimately changes the compresion ratio the 76 cc will lower the comp. and the 64 cc will raise the comp it just depends on the pistons, head gasket thickness and if the block has been decked or even if the heads have been decked,or if the piston is in the hole or has been zero decked...it all adds up in the end:)

Try to find a set of 58cc chamber heads....could raise your compression about 1/2 point

Originally posted by 1BDYJ
Try to find a set of 58cc chamber heads....could raise your compression about 1/2 point


I'm not too sure what I'm going to do, they're the old double hump heads, which have a great reputation. I was just wondering cause I have a line on some 882, but I might just stick with what I have, and rework them when the time comes. Plus I can't think of any reason to lower my compression ratio.

Keep the double hump heads...good set of heads!!
You need to try to find the source of your blow-by...do a compression test on all cylinders and see what you get.
Smoke out of the tailpipe on initial start up could be valve guide seals...
Smoke out of the tailpipe driving down the road could be rings...
Smoke out of the PCV grommet is normal to some extent..thats why its there..to recirculate crankcase pressures.
Make sure you have the right PCV valve...try an AC DELCO CV774C It should be the correct one for your engine.
Every engine has some amount of blow-by, so unless yours is very excessive, I wouldn't put too much concern to it unless your compression test says otherwise.
Good luck

Originally posted by 1BDYJ
Keep the double hump heads...good set of heads!!
You need to try to find the source of your blow-by...do a compression test on all cylinders and see what you get.
Smoke out of the tailpipe on initial start up could be valve guide seals...
Smoke out of the tailpipe driving down the road could be rings...
Smoke out of the PCV grommet is normal to some extent..thats why its there..to recirculate crankcase pressures.
Make sure you have the right PCV valve...try an AC DELCO CV774C It should be the correct one for your engine.
Every engine has some amount of blow-by, so unless yours is very excessive, I wouldn't put too much concern to it unless your compression test says otherwise.
Good luck

Actually, I had white smoke blowing when I got it, then when I replaced the plugs and wires that went away. But I blow a shit load of oily smoke from the valve cover hole, so I just have that vented into the frame on one side and have the PCV still hooked up on the other. Does it matter which side of the engine has the PCV valve on it, because I tried switching them and it didn't matter? I have a compression tester, I just have used it yet.:D

I run the pcv from the drivers side v/c and get the vacuum source from the back of the carb (middle port--big one)...the other valve cover should get a breather element to allow air into the engine.
You can do like the racers and run two hoses off of the valve covers to a catch can on the frame and periodically drain it!

Originally posted by 1BDYJ
I run the pcv from the drivers side v/c and get the vacuum source from the back of the carb (middle port--big one)...the other valve cover should get a breather element to allow air into the engine.



That's the weird thing, the open side doesn't pull, all it does is blow smoke. Maybe I'll try running to the larger vacuum port, but I think my brakes are on that one.

If you run brand new vortech heads from chevy they are $400 or $500 brand new with I believe 54cc combustion chambers.

Originally posted by Weelr81
If you run brand new vortech heads from chevy they are $400 or $500 brand new with I believe 54cc combustion chambers.

According to MorTech the Vortech L31 heads come with 64cc size combustion chambers. I didn't really want to drop $400 just for heads. Thanks though.:D

DON"T swap to the 882 heads. They are a light weight "smog" casting, that is very prone to cracking around the exhaust ports.

Where do you get the 882 designation? I was just browsing the GM online catalog and I couldn't find that number anywhere in their head reference chart. :confused:

Originally posted by brector
Where do you get the 882 designation? I was just browsing the GM online catalog and I couldn't find that number anywhere in their head reference chart. :confused:

It's the last three numbers in like a 7 or 8 series. So it's something like xxxx882 or xxxx041. Here's a good site for looking up Chevy infoMortec (http://www.mortec.com/)

Originally posted by FattyCBR


According to MorTech the Vortech L31 heads come with 64cc size combustion chambers. I didn't really want to drop $400 just for heads. Thanks though.:D they may not boost your comp ratio but look into these heads, they really are bad ass. They flow really well even with the smaller valves, something to do with the fact GM has millions to spend on R&D