[blackchevy3de]

i have a 385 gm fast burn roller engine with a fact installed 383 roller cam , what can you tell me about these motors , it runs great but is it normal for these engine to be noicey on start up tell warmed up,sounds like valve noice but valve adjustment was checked and is rite zero lash and a 1/2 turn thanks jim

[65GTO455]

Dumb question.... are you checking it with the engine running and fully warmed up?

[crussell85]

piston slap, cylinder walls are over bored

[sri3850341]

classic result of forged pistons, if theres no blowby present then theres no reason for concern

[American Muscle]

Originally Posted by 65GTO455

Dumb question.... are you checking it with the engine running and fully warmed up?

Only dumb question is the one not asked. In my opinion this is a poor response

[68NovaSS]

Originally Posted by sri3850341

classic result of forged pistons, if theres no blowby present then theres no reason for concern

Why would you say that?? I've never had piston slap or rock with forged pistons in a correctly built motor, and I've had many.

[327NUT]

"classic result of forged pistons" I don't think so, the 385 Fast Burn comes from the factory with hypereutectics with very tigh clearances.

[sri3850341]

Forged pistons are known for more expansion, larger ring gaps are my reasoning for assuming a forged piston had more expansion properties vs other hardening/manufacturing techniques,guess i was wrong. the 385 had hypers?did not know that till now,maybe i should not have been so eager to reply, next time i will make sure before hitting that reply now button..

[American Muscle]

Originally Posted by sri3850341

Forged pistons are known for more expansion, larger ring gaps are my reasoning for assuming a forged piston had more expansion properties vs other hardening/manufacturing techniques,guess i was wrong. the 385 had hypers?did not know that till now,maybe i should not have been so eager to reply, next time i will make sure before hitting that reply now button..

wise choice because these will eat you alive. When posting facts make sure you have evidence to back it up

[sri3850341]

Originally Posted by American Muscle

wise choice because these will eat you alive. When posting facts make sure you have evidence to back it up

Understood.. i dont want to be "eaten alive", i will try to keep my learning silent from now on.. Thanks for the heads up.. You can see by my post count that i am a "newb", so please have pity for now...
To the op, sorry.. Maybe your lifters are bleeding down and ticking, i know you said till warmed up but, approx how long before the noise goes away? And how long does the engine sit when it happens?

[65GTO455]

Originally Posted by American Muscle

Only dumb question is the one not asked. In my opinion this is a poor response

I meant I had the dumb question. His was by no means dumb. Sorry for not clarifying.

[American Muscle]

Your question wasnt dumb either. You ask questions cause you dont know, you ask questions when you wanna find out. When I was in college i raised my hand all the time like I was in grade school. People usually asked me for info cause they knew if i didnt know the answer Id raise my hand and find out for all of us. Never think a question is dumb

One of my college professors use to always say "if you cant learn continuosly the world cant use you"

[327NUT]

To SRI....Hell I don't know all this stuff, Google is your best friend!! Most of the questions asked can be googled for the answer. One of the worst ones is "what does my sbc casting number mean?"

[cobalt327]

Originally Posted by blackchevy3de

i have a 385 gm fast burn roller engine with a fact installed 383 roller cam , what can you tell me about these motors , it runs great but is it normal for these engine to be noicey on start up tell warmed up,sounds like valve noice but valve adjustment was checked and is rite zero lash and a 1/2 turn thanks jim

Diagnosing engine noises can be hard to do even when standing beside the engine, let alone on the 'net.

The cam has a lot of lift w/o a lot of duration, and uses stamped steel rocker arms. This can contribute to some 'extra' noise. This would be heard from the top of the engine, at the valve cover level.

If you're hearing something lower on the engine block, this could be caused by a piston(s) w/the skirt partly collapsed from overheating, or a loose wrist pin, or even excessive bearing clearances.