I've had this problem with my 2nd gen before and was never able to fully resolve it, but I figure I'll ask here anyways since I'm now having it with my FB as well.

at high ENGINE rpm it ******* vibrates! no smooooootheeeness like it should be.

any idea as to what's wrong?

this happens witht he car parked, just revving it, and also while I'm driving -so that eliminates anything past the transmission from being the problem.

on my FC I've replaced EVERYTHING and nothing has fixed it - not even changing the engine, transmission, nothing!

about the only thing I can think of is that I've always used the same brand and weight of oil, but I don't think that that's the issue.

Anyways... if anyone has any ideas on my FB, I'd love to hear them.

the only modification to the car (under the hood) is a 2g coil - I never really drove the car much before I put it on- so I can't comment if it is the cause of the problem or not.. could timing be a factor?

 

have you ever thought about changing engine mounts in either or car? also anything carb related could attribute to vibration.

 

I've tried many different types of engine mounts in the 10AE - I've had the vibration in it disappear briefly a few times but never for good.

I haven't changed them out in the FB but they "look" OK and the engine doesn't rock.

 

maybe your cam profile is too aggressive....


in all seriousness: check that crap-*** shutter valve.. that thing was a host of problems for us.
also make sure you're getting enough fuel flow and good ignition, and maybe clean out the engine (carbon deposits could unbalance the rotor assy's)

 

Drive shaft? It's probably a long shot, but you never know. Have you ever hit anything or done anything that could have put it out of whack a little?

 

Transmission mount should be checked also.... basically check everywhere the engine is attached to the car. The only other avenue I could suggest is an electrical break down at higher RPM or under demand.

 

Make sure that no part of the exhaust system is in direct contact with the frame, body, or drive train. Exhaust is supposed to be mounted using rubber insulators to avoid vibration issues. The only solid contact point should be where it mounts to the engine...

 

Miss firing during high rpm possibly from a bad signal source with the 2g coil upgrade. Check your plugs and wires and see what the resistance is on them. It's cause on piston engines but it may occur on a rotary? I really don't know about that but hey it wouldn't hurt to check.

 

Maybe your expectations are too high?

 

lol peejay....

 

Define high rpm. My 12A vibrated pretty bad past 8k.

 

Not "lol"... even electric motors will vibrate. Just because it is a "smooth rotary" doesn't mean it's vibration-free. In actuality, most modern fours and sixes are smoother than rotaries.

That's what needs to be quantified. Are we talking "the car jumps up and down" or is it just buzzy?

 

compared to my friends '87 GXL, it shakes like hell.
compared to my '91 4g63-powered talon, it shakes like hell.
compared to my 10AE when I bought it orgionally and when it works properly, it's buzzy