Roush wants my Alum. FE 511 motor

[Spoooky]

That's a good question. How do the rings get stuck? Roush wants the motor to run with very light weight oil, 10w-30wt, conventional only. No synthetic. I thought it might be a heat thing and my motor runs right at about 200 degrees oil and about 210 degrees water. That is right on. I know that the FE/ alumn. big blocks run a little hotter. Mine is right where it is supposed to be. I've been going through a little oil right from the start. Roush does run these wide open before you get them. I don't have the answer. It does run great though. I'll keep everyone up to date as I get the info. Good stuff to know.

[vettestr]

Rings can loose their tension and allow oil or compression to pass by them, overheating is the most common reason. Many racing rings are designed to have a lighter tension and use gas porting to help expand the top rings. Aluminum engines have steel sleeves because the aluminum is just to soft. Sometimes carbon make rings stick in the ring-lands of the piston. The groove accepting the ring on the piston (ring-land) becomes deformed from pinging, heavy detonation or even breaks the rings so they fail. Some rings just never seat or seal against the cylinder walls.

When you think about the speed a piston must travel it is a little amazing. A piston in a 4.0 inch bore at 6000 RPM travels 66.6 feet every second but only gets 4 inches before it has to change direction.

[Spoooky]

Jeff,

You are exactly right. Heat! I'm not sure if they even really seated yet too. Remember only 1000 miles on the motor.