[jjgrizz73]

hey everyone. I just got done restoring a 67 camaro. We are having a vibration issue in the drivetrain. We just installed a new M22Z transmission in it as well as a rebuilt 454 with a new Kissler bellhousing (was within specs for register bore) I have a vibration I can feel through the shifter going into and out of the throttle. If you let off quick it will vibrate quickly then stop same if you get on the throttle. If you feather it the vibration lasts longer. Any ideas? There is new U-joints, not sure if the driveshaft is balanced because it came with the car. I dont want to hurt the new transmission because it was hard to get ahold of these Masiero gears.

Thanks in advance!

[parkbrau]

Check your drive shaft angle. Here is a link to assist:

http://www.iedls.com/asp/admin/getFi...&TID=28&FN=PDF

[jjgrizz73]

Ill be the first to admitt Im lost when it comes to checking these angles. I did however drive the car more to see what other problems it was having. Heres the breakdown

in 4th gear @ around 2,000 rpm it will give a vibration when slightly in throttle, this vibration will go away when you let off the gas completely or get on the throttle more heavily.

while coasting (downhill as ex.) if the car gets put into neutral it will make a vibration and a almost clunking/grinding type sound with the clutch engaged and disengaged until you slow down then it disappears.

Thats the only real things ive experienced, it also makes me cringe shifting at higher rpms because when the clutch goes in theres a vibration.

Does any of this sound like anything particular?

[69-Pace]

Wow sounds like maybe a syncro issue? I have no first hand knowledge of a rock crusher version but assume the setup is the same just a different helix cut on the gears. Have you eliminated the unbalanced drive shaft as a cause? Could just disconnect and drop the shaft from the Muncie at the tail, and see if you get the same sounds as coasting in neutral as you shift and put power by throttling up and down in gear, but if the vibration and grinding noises are being caused by the drive load or the rear end you won't hear it.

[jjgrizz73]

The "grinding" sounds isnt a grinding sound like the grinding of gears. Maybe it was a bad description. Its just tough to describe. I dont see it being a tranny issue you at all, I trust Greg @ MuncieRX did a goodjob building it. I didnt eliminate unbalanced driveshaft but I figure if that was the case it would vibrate all the time? Its just only in the circumstances I listed does it vibrate.

[jjgrizz73]

Also was thinking might be possible to run it on my lift with and without the driveshaft to see about eliminating anything, good idea?

[69-Pace]

yeah that or for those poor folks like me without a decent home garage without a lift, jack stands but keep your safety in mind with those.

[jjgrizz73]

I didnt get to testing it yet without the driveshaft but here are a few pictures showing the rear angle. I think its pointed too much downwards...any opinions?



Front:

[Fred Ficarra]

Yep, too low. Mine was about the same as yours since it was new and had similar symptoms as yours. The solution was to wedge the spring pads to raise the pinion six degrees. Problem solved. I'm a believer. Mine had that vibration for 38 years. It's gone now.
You want the imaginary line of the engine/transmission as it's extended rearward to be close to parallel to the imaginary line of your rear pinion. Here;http://www.streetrodderweb.com/tech/...les/index.html

[97Z4C]

i agree on angle causing problem--is the cal tracs adjusted too far-need neg 2 deg. -the rearend should look almost in line with driveshaft but leaning down a hair---got the right engine stands in it small block and big block are different--tranny mount are different between auto and manual==maybe look more toward how tranny and engine is setting than rearend

[jjgrizz73]

The stands are correct, motor sits forward and towards the right and the mount is also correct. The motor and tranny sit at a slight downward angle. But that rear is def angled downward. The CalTracs I never adjusted, I only tightened the bar until there was slight pressure on the leaf springs. I can however tighten them slightly to bring the rear back up, but I think I will still need shims...

Heres where I am as of now. I ripped the tranny back out of the car to replace the dowels with those EZ Offset dowels and will make the register bore perfect. I was kind of worried about the condition of it but it looks fine. There is 4 leafs in the back of my car plus a small leaf sized block under them. Im going to remove the small block and see where that puts the angle. The car sits super high in the back so it cant hurt. I will have to shim it from there:

[MTN10]

Good looking car

[97Z4C]

good luck -looks great right on trck what your gonna do