Transmission Vibration

[TK3cobra]

We are building a cobra kit with a 427 and the Tremec TKO 600 transmission, along with IRS. We are experiencing a sort of transmission vibration when letting off the gas. While it seems to be worse in 3rd and 4th gear, we think the vibration is being caused by the driveshaft angle? Has anybody had to use transmission mount spacers for similar problems?

[silver_pilate]

Lots of people have had to use spacers to get their pinion angles where they want them. It's easy enough to make your own, or folks like Forte have them in stock usually.

[SJDave]

I went through a similar problem on mine, turned out to be an OUT OF BALANCE PRESSURE PLATE. It was a King Cobra clutch made by Valeo purchased thru Forte. I had to take it to an engine shop to have it dynamically balanced, they added about 1.5 ounces of weld material to the outer housing. What do you know, no more vibration.

[CraigS]

I will go out on a limb a bit and say that, based on many threads here over the years, a 1/2 to 3/4 inch thick trans spacer is the norm.

[GoDadGo]

Here are some oldies but goodies from Spicer that we've been sharing for years regarding Driving Shaft Angles and U-Joint Phasing:

https://youtu.be/Idk3BVDVHq4

https://youtu.be/jaaTyL099RA

Good Luck & Please Keep Us Posted Regarding Your Progress!

[RBachman]

Mike Forte' has a nice spacer kit for the transmission.