KA24DE high rpm shake

[kent624]

I have a mostly stock 1995 s14 that around 4600 rpm it starts to shake, harder than a vibration and progressively gets worse as the rpms get higher. It does it in gear and in neutral also my shifter shakes like hell. Ive replaced the motor mounts, cap, rotor, plugs and wires. The car runs perfectly fine otherwise, at idle and while accelerating until then. I try to stay out of the high rpms but its been bugging the crap out of me. I do have a megan racing trans mount which might be the culprit but I think thats unlikely. I noticed some popping on deceleration from the exhaust after i installed an Apexi N1 dual, im guessing that its backfiring? I didnt notice it with my stock exhaust. I've searched and think it could be the timing, i havent checked that yet nor know how to or a misfire? I need some help!!!! I think this is my fist post by the way!!

[JonTheGreek]

Try to get a hold of stock transmission mounts. Borrow one of your friends, i'm sure they wont mind. Next try to get a hold of a timing light and check to see if yours reads 20 +/- 2 BTDC. You will need to have the engine warmed up and disconnect the throttle sensor. To make an accurate read. Also make sure your idle falls between 650rpm +/-50. Let us know, good luck.

[Mikester]

+1 on transmission mount...

It's important to match the motor & trans mount. Stock motor mounts & a hardened tranny mount will tear the tranny mount; which could cause what you are describing. If you used Megan or Nismo motor mounts, your problem is elsewhere. Also, the fact that this does it in neutral tells me that you should prolly look at your crank pulley & other accessories- I'm pretty sure that the crank pulley serves as the balancer for the bottom end.

If I were you, I'd work to find & fix the problem. If it's the crank pulley or anything in your bottom end, you could be wreaking some havoc on the bearings/journals...

I'm not a mechanic or machinist so don't panic lol... But it sounds like you should really look at what's going on instead of just keeping it below 4600 rpm ;)

[JonTheGreek]

I agree with the crank pulley, harmonic balancer. Do go cheap after market! I dont know what you have but either stay stock or go for a well made/balanced harmonic balancer. Mikester is right you will run through your bearings.