Anyione ever blown a cometic head gasket

sleeperz28
07-20-2005, 02:13 PM
I had a rocker arm come apart on me during a pass. I sent it in for repair, then got everything back together over the weekend and now I have a terrible miss. Its not like a shake here and there its almost like a blown head gasket where the car will not pull anymore because its missing so bad. Here is the strange thing:
1) car doesnt miss daily driving or anything under 10psi.
2) Leak down test reveals all cylinder with in 10% of each other
3) all plugs look good and are new
4) Cap and rotor I scrapped all the carbon off so looks new again

This problem happend right after the rocker arm came apart. #4 is the cylinder were the rocker came apart and that has the highest leak down. Im wondering if a small amount of coolant is entering the cylinder? Doesnt seem to burn water and there is no water in the oil or rad.

What you guys think?

marshall93z
07-20-2005, 02:37 PM
Maybe it's just lifting the head under boost? How much boost do you run?

And what does that thing run with all that power?!!

Z8'S
07-20-2005, 06:10 PM
What heads are you running? I experienced coolant leak only under boost thru a crack in the combustion chamber This was with GM LT4 heads also heard of it happening to another boosted car with same heads. Only indication was one plug would be slightly wet when changed. just a thought ;)

sleeperz28
07-21-2005, 04:08 AM
Im running the AFR220 heads. Its a tough call. i know its not lifting the head I have had this comb 2 long with no problems. Im just not sure if these all steal gaskets can get pushed out enough to leak...When I poped a gasket before it sounded similar, but this time I got no milkshake in the oil. I even tried cranking the cylinder pressure up with the leak down but nothing changed...

sleeperz28
07-21-2005, 07:22 PM
Ok I was wrong when I said all cylinders are 10% from each other. I ment close to 30%. It seems that #1 cylinder has fairly poor leak down and would benefit from a rebuild. Its at about 70% leak down. The best cylinder is at 42%. Now would a difference such as this cause a major miss fire?

sleeperz28
07-22-2005, 02:20 AM
Just an update I found corrosion on a few of the wire tips. Everything rips again and feels stronger then last year :cool:

Turbo6
07-22-2005, 10:09 AM
Quick question for you on your AFR 220's, what type of valvetrain are you running if you don't mind me asking? Rockers, lifters, etc, thanks.

sleeperz28
07-22-2005, 12:56 PM
Crower shaft rockers, crower push rods, crane lifters cam motion cam

Turbo6
07-24-2005, 05:47 AM
offset rockers? How much offset?