Crankcase evac ????

[cdignition]

Hi all..I am going to install a Moroso Crankcase evac. system to my 500" motor...Tomorrow, I will have the fittings welded to my JUNK Headman headers...I ran this motor some today and sprung a leak...so I guess it needs some vacuum...How much vac do these systems make?...I will run an exhaust system, but venturi effect should still pull some vacuum, even with some backpressure....at the Track I will run open headers. I just need it to stop popping leaks while im on the street(3rd one for the stupid chain cover grrrrr) BTW, the Chrome Chain cover is JUNK...Make sure to grind all the chrome off of the sealing surfaces..it will leak otherwise...mine still is leaking(hope the evac stops it)...Input anyone???

[morrisbrw]

One sure way to stop the blow-by in your engine is to drill gas holes in the top of the pistons. The hemi engine came from the factory with them. Drill the holes around the piston where the pressure will enter and push the top ring out against the cyl wall. Five in the top is enough and about 1-32 in diameter. Be sure to drill all in the same place on all 8 pistons and 5 holes in all 8 pistons or you will mess up balancing. Use good rings. Some of the rings work fine in an engine that will be used for daily use but rev it up and the rings will hydroplane on the oil on the cyl walls.

[HOLESHOT]

this setup is suppose to work well,never used one myself but Id check ring leakage since any good engine should not create this much pressure,are the rocker covers vented?Is the crankcase over full?Keep us posted on your results.

[amoparguy]

morrisbrw says, One sure way to stop the blow-by in your engine is to drill gas holes in the top of the pistons. The hemi engine came from the factory with them.

I don't claim to be an expert but I've never seen or heard of factory Hemi pistons with gas holes. I'd like to know more about it....did they use them on Race Hemis, Street Hemis or both? And what years? I'm always trying to learn more about those legendary Hemis.

[blackcuda]

Hey guy's I thought that gas porting was for race only engines. Did I miss something? It seems I read and/ or was told that gas porting would load the rings against the cylinder walls very hard and that the rings would not last very long. I know that the hemi race engines used 'em but I think they also used a dykes type ring that was designed for this purpose. IMO, unless I missed something they should be used in race-only applications that you tear down often and replace the rings, so probably not a good idea for a bracket racer either..........

If I did miss something, please let me in on this! I'll start tearing my ole 440 down ASAP!

[blk66sat]

Gas ports on a street motor is a waste of time its a race only thing ,Gas ports get filled up with carbon. my2cents