Rebuilt Heads
Thread Starter
Heel & Toe
Joined: Sep 2005
Posts: 23
Likes: 0
Rebuilt Heads
So I the heads rebuilt - port n polish...and took it for a test drive the other day. First off, when I would accelerate, at times I would get some chatter still. Is that possible they didn't put the screws on proper pressure 
. Also, at high speeds (70+) and I punch the gas, I get a loud knock...lag...then speed. Any ideas? I haven't taken it back to the shop yet, just thought I would get your opinions first so they won't try to 
me.
Thanks
Daniel
. Also, at high speeds (70+) and I punch the gas, I get a loud knock...lag...then speed. Any ideas? I haven't taken it back to the shop yet, just thought I would get your opinions first so they won't try to me.Thanks
Daniel
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
is this noise only happening under a load situation??? if so i think your timing may be off causing detonation....and detonation is very serious and can destroy an engine very quickly
Thread Starter
Heel & Toe
Joined: Sep 2005
Posts: 23
Likes: 0
Hmm...
Well I suppose it could be detonation. I'm not too sure, since it only happens maybe 1 out of 5 punches of the gas at high speeds. As far as the heads were concerned, I had 3 shops and 2 gearheads look at it before I took it in and they all agreed the chatter that I was receiving before the rebuild was due to the heads. Plus I was getting no combustion in chamber 3 and my oil pressure was complete wack (no its strong as hell). As of right now, the chatter comes and goes (not as bad as before) at speeds between 20 and 50. Usually I don't notice it at high speeds, just the knocking at times. BTW, from research I've done on detonation, apparently you can drive thousands of miles with llttle or no damage. But thats not to say it's worth the risk 
.
Any more ideas would be great,
Thanks,
Daniel
http://www.streetrodstuff.com/Articl...ne/Detonation/
.Any more ideas would be great,
Thanks,
Daniel
http://www.streetrodstuff.com/Articl...ne/Detonation/
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Check your timing and advise what you find. What compression are you running? On my '80 L48, with its lower compression, I run alot of initial timing, around 25 degrees BTDC at idle and the engine loves it. All advance is 'IN' by about 2500rpm with 35-36 degrees BTDC. Higher compression engines will not tolerate as much advance up front. Would be good to know how much advance you are seeing at idle, by 1500rpm and then by 2500rpm. You may be getting full advance too early.
