Hears a question for you guys I fire up the 455 and you can hear a noise which i think is piston slap. I run JE forged pistons, is this common, because as soon as the motor gets heat in it it stops. motor has good oil pressure 60 when cold at idle and when full warmed up holds 20 in gear idleing at 900RPM. is there anything you can do to fix this or is it normal
Bryan, If it is piston slap, theres nothing you can do about it. Forged pistons need to be set up with more piston to wall clearance because they grow more when they heat up. From what I've heard and read, it sounds worse than it is. I know some of the late model LS1's have an issue with this. Find out if your engine builder set the clearance right. If he did, it's something you have to live with. I don't think it's harming anything, its short lived until the pistons heat up, which should happen pretty quickly, right?
yeah as soon as the motor gets to about 140 it stops. maybe i am hearing valvetrain noise. who knows. if a person worries about every little tick on an engine, they would never be happy because engines make noise. thats life. i have checked oil filters often for metal but nothing in there looks good. motor has about 1200 miles on it
along with larger tolerances required for forged pistons, as stated above, most forged pistons come with wrist pins set to exact center. Factory cast pistons were made with a small amount of pin offset to eliminate the very problem you are experiencing. That is why they have marks to denote direction of installation. The clatter doesn't hurt anything and delivers 100% of your explosion to your crank. Rattle on!
