Okay i just put 500miles on my motor, and did a compression check, and the front came out 120psi, and the rear came out 92 psi. When i pulled my spark plugs they did have a little dirt and depris on them. Im havent changed the oil yet but i am very soon. Right after the rebuild both rotors had 88psi.

The parts i used were atkins rotary apex seals, solid corners, all new springs, new oil rings, basically everything brand new, etc. The irons and housings were used and seemed in fair condition.

I just wanted some suggestion on what the problem could be? I didnt really throughly clean my engine rotors that well, and could some dirt and other crap not make my side seals, and apex seals spring up corretly enough?

The car does run great, but has a rough start sometimes when it is at operating temepertures, but it has gotten better over time with the gaining mileage. Overall it drives well.

I let it break in slowly, meaning i tried to keep it under 3000 rpm during those 500miles. Currently the car has about 550miles. Should i drive it up to 1000miles and check it again?

-Thanks

 

Give it a little more time...People are so obsessed with compression numbers. As long as the engine starts, makes good power and runs well, who cares what the compression is?

Now, it could be a number of things. If you are using a normal compression gauge you are only measuring average compression of that rotor. So you may have a worn housing, improperly clearanced seal, etc.

That's a large compression difference that indicates something is up with the bad rotor. It is important to get the rotors clean but as long as the seals move in their grooves, they are clean enough. Beat on it a little and see what happens.

 

I agree with Aaron. Stay out of boost, but start increasing the RPM's to around 4-4.5k.

Are you measuring each pulse on the compression test, or just getting MAX pressure readings? Either way, get that oil changed and put some more miles on it.

 

I don't mean to thread jack, but I have a new rebuild I installed this summer and wonder what kind of break in period I should be using.

Atkins told me 500 miles below 3500rpm's and then add 500 per week till I get to redline. Is this a little excessive or do you think this is a safe route. Its a stage 2 street port if that matters.

 

that is a rather strange schedule to follow, yes. beats the people who tell you to baby the hell out of the motor for 3K+ miles though..

 

Sounds to me like you used a really nice housing up front and a lesser housing in the back. IF that is the issue, the difference will never really be made up. The strong front rotor should always be enough to keep it going pretty well, though, so I wouldnt worry about it unless it gets worse.