I'm interested in buying a 10AE. The owner of the car(member on this board) let me do a compression test on it. According to RotaryRessurection's tech article on how to do a compression test, you're suppose to insert the compression testing on the lower plugs. We didnt do that. We inserted the compression tester into where the top plugs are supposed to go.

The results for the front rotor were 90-90-90 if we held the vent valve down. And 110 if we cranked it for 5 seconds. Same results for the rear rotor.

My question is, are the results going to be different if I did the same thing but used to lower plugs. Thanks

~Dave

 

I think i remember trying it on both leading and trailing spark plus holes, with the same results for both.

 

Are those compression numbers good?

 

Yep

 

Yes, those numbers are fine.

 

between 90 and 110 is good....

 

Sweet, cause the motor(original) has 76k miles on it. How many miles could the motor last if its treated the same it has been. Just out of curiousity. I know this is not a realistic question. But I'd like an estimate.

Also, what does the 90-90-90 mean when I head the valve down and cranked it.

Thanks
~Dave

 

115+ is like new, 100-115 is healthy, 90-100 is getting weak(1 year or less in most cases) below 90 could blow at any moment.

from rotaryresurrection.com

 

but from past expecence a engine will prob run good till about 80 psi compression

 

It means that each rotor face, (3), made 90psi.

 

ok

110psi in top holes is FANTASTIC numbers.

I'd say anything above 90psi is good, 80-90 fair, below 80 is almost gone.

 

Do you have a link to this compression test? Also how does this test differ on ported engines?

 

Another reason why I don't advocate what other people might or might not have experienced. My 90 vert had 74psi in all 6 chambers and still runs, and starts on the first try everytime, with a handfull of mods, and redlined daily.

Been that way for 3 years now, and still going.

 

Whats the difference using the top holes and bottom holes? There must be a difference if RotaryResurection specifies to use the bottom holes, right?

 

i think there could a possible diffrence of a few lbs, if u really wanna get the max compresision take 1 pug outta both housings and put a cranking amp charger on the battrery, then see what it says.. p.s your in mass toooo, ill have to check it out sometime, how much u paying for it it want a 10ae!!!! haha

 

Top or bottom plug hole, doesn't matter. I've done both, always got same results.

 

again, does a ported engine make a difference on compression numbers?