i don't know how to tell what is wrong with my engine. it shakes violently below 1200 rpm but is smooth above that, it feels like i am only running on one rotor. can anybody tell me what might be wrong

 

Check compression and come back with the results. We can't tell you anything without info.

 

do i check the leading or trailing plug for compression

 

How violently? The engine is known to "stutter" in first and reverse in low RPMs.

 

the whole car shakes and rocks, not normaly. very visable from outside of the car

 

I think leading(or the bottom i think thats L) but i believe u have to leave both plugs out to check it.

 

I don't think it doesn't matters what you use leading or trailing since they should both see the same compression, And you need to leave one pulg for each rotor in or else all the air will leak out.
Alrhough I think trailing would be easier to get too.

 

I meant 2 plugs as in both leading plugs....not the trailing and leading...so both bottom plugs on each rotor