Supra Motor Vibrating???
 

Hi so my bf has a 89 supra. The 7mgte motor was completely rebuilt by rebellas, it's a five speed turbo. When his car reaches 4000 rpm the motor starts vibrating(the speed doesn't matter) as long as it's past 4000 rpm it'll vibrate. His clutch is an eBay stage 2 XD or something, im not quite sure which one exactly, and his tranny isn't very good, sometimes second gear pops out. Also he needs to change the wheel bearing in the driveshaft and his rack and pinion is a little messed up. (I'm just giving any info I can so u guys get a good sense of what the problem might be with the vibrating)
any input Is helpful! He's getting his car tuned over in santa rosa this weekend and we need answers asap, so any help is appreciated! <3
Oh and the clutch is supposed to hold 390 HP. ( I don't kno if it can handle the power. The supra is at least 350) if u n?ed any more info let me kno!! Thanks!
oh and also he can shake the right front tire, side to side which is baddd, but i dont think it has anything to do with the vibration because we found out that, like i said, it only vibrates after 4000 rpm, no matter the speed of the car.
Thanks again <3

Sounds like maybe the dampener in the harmonic balancer has shifted. Is he running the stock harmonic balancer? If so, what condition is it in?

Look at the drive line see if the is marks where they separated it. If they didn't put it back together exactly how it was balanced that's ur your problem! I kno ya say speed doesn't matter but at 4000 rpm or should be about where ur gettin boost it is putting a lot of torque on the drive line.

What mods does he have to suspect 350hp?

Get ur ball joints repaired asap also. That doesnt help vibrations

And id be surprised if that clutch will hold 200hp. I've heard nothin but bad things about them! There is a reason why they only sell for bout 200 bucks! A good clutch for higher HP will run you around 400 bucks atleast! Do a quick Google search on eBay clutches!

I guess to help narrow this down, does it vibrate when the car is still and the transmission is in neutral? Does it still do it with the clutch pedal pressed down?

Well his turbo kicks in at 2500 rpm, and full boost at 4000.
I suspect 350 cuz he beat a gto and I think they are around 350 hp. His mods Im pretty sure I turbo I think from driftmotion, but the turbo is stock but sent it to driftmotion an is 57 trim. But he's pushing 14psi, He has exhaust 1000cc injectors, the motor was rebuilt by rebellas. And he's tuned by a guy named Lawrence, he's running on ethanol too.

And yea everyone has been saying the clutch so far, but I'll ask him about the other stuff.
*BTW i asked him about the drive line and how you can tell if its balanced. but can you explain a little more clearly how you can tell if its not balanced correctly?
*He also says that when he is in 1st gear lets say, and he revs it up to 4000 rpm it starts vibrating, and even when he presses in the clutch it still vibrates...

supra motor vibrating
 

Hi!
Did you find the cause of the vibration? - as a thought- release the tension from ALL of the drive belts and check that the harmonic balancer has not come loose , may be the cause, mine really rattled before I fixed it .