pulsating problem!

[460_f100_dude]

anyone elses motor like pulsates durring break in? i can keep it at constant throttle itl rev up but it always pulsates and never one constant rpm anyonr know what could possibly be wrong? could it be that i installed my piston in wrong when i got my new case? i put the u shaped cut out side towards the exhaust is that rigth thanks darren

 

[izitbrokeyet?]

Sounds like you have a piston skirt installed on the exhaust side. :- That would be on the wrong side dude.....and may be your problem