Normal vibrations??

[Paul Workman]

I notice that between approx 6300 rpm and "cutoff" (approx 7200) a vibration is present - enough to make the dash "buzz". I don't notice it in 1st or 2nd gear, but then the dwell time in that range is very short. I notice it in 3rd gear and above.

Is this "normal" for the Zs, or should I start thinking about pulling it apart at some point to see whatz up?

TIA,

P.

[tccrab]

More than likely your transmission is not aligned correctly under your car.
The top of the c-beam should be 45mm from the bottom of the floorpan and the c-beam should be 28mm from the drivers side.
The buzz you hear at WOT is the transmission riding up under the car and some part, maybe the shifter, maybe the transmission, is touching somewhere and transferring the buzz into the cabin.

I just learned this while talking with Marc Haibec last week. I had asked him a few questions about shifters & boots when I was replacing my transmission. I asked him how important it was to align the transmission and that's when he told me that if it wasn't exactly where it should be that under WOT the car would buzz just like you describe.

If you have stock exhaust there's just enough room to get at the c-beam bolts to loosen them up. Just loosen them and let the transmission hang down on the bolts. Cut two pieces of wooden dowel, one to 45mm the other to 28mm. Use them to measure the top and side of the c-beam to the body of the car. Adjust the transmission by lifting or lowering it on a jack and or prying it from one side to the other.
Then re-tighten the c-beam bolts.
There is no easy way to get a wrench on the nuts on the top of the c-beam. Be prepared to get creative and be prepared to need band-aids and BenGay afterward.

Bring it on by the house, I'll fix it up for you.

TomC

[Paul Workman]

...In fact, I still have my gauges from the time I replaced the ZF in my '95/LT1. I remember Bill B mentioning it was important to be sure the ZF was properly aligned, but he didn't say (or I wasn't paying attention) what would happen if it wasn't aligned. Thanks for that bit of info. I'll check it this w/e. (I gotta check to see that I have a good supply of bandaids and Aleve on hand.)

I'll let y'all know if that does the trick or not. Wish me luck!!

P.

[tomtom72]

Hey Paul, just in case you don't have beam plates, I have the tool that Bill includes in his beam plate package.....it is used in place of a wrench on the stock C-beam bolts' nuts so you don't have to fight getting a wrench up top.

I'll more than be happy to share, just let me know &I'll send it to ya. I think they also are dual use as spacer gauges...go-no go type gauges....not too sure about that so check his web site on that one.


Tom

[Paul Workman]

Originally Posted by tomtom72

Hey Paul, just in case you don't have beam plates, I have the tool that Bill includes in his beam plate package.....it is used in place of a wrench on the stock C-beam bolts' nuts so you don't have to fight getting a wrench up top.

I'll more than be happy to share, just let me know &I'll send it to ya. I think they also are dual use as spacer gauges...go-no go type gauges....not too sure about that so check his web site on that one.


Tom

WooHoo! I'd be happy to take you up on that offer, cuz I remember how much fun I had the first time. I'm pondering contacting Bill B and having him send me some beam plates. Course, until I get underneath, I don't know for sure whether or not there may already be some on the car. Stranger things have happened!

This is going to be such a nice w/e - Sunday especially. Mebby I'll hold off this w/e and perhaps "drop by" in the Z and save ya the postage?

PM me if that works for you and I'll check with the "war department" for timing conflicts.

P.

[GOLDCYLON]

Im running the beam plate package on my car. Damn if I really knew waht they were for before this post besides which Bill had posted beyond flex and tourque.

[95ZR1#418]

Originally Posted by GOLDCYLON

Im running the beam plate package on my car. Damn if I really knew waht they were for before this post besides which Bill had posted beyond flex and tourque.

When I first bought my car it would jump "big time" to either RT or LT after a shift- very scarry, especially on the narrow MT back roads where I let it go. I installed Bills plates as per instructions. I was very exacting in the alignment and used the 3M window weld to "epoxy" the U channel at each end. Torqued per spec etc.

The car lays dead straight now; never the slightest fishtail or angle during acceleration & shifting.

When installing a new ZF-6 one of the bolts strippped(nut turned in its compartment) while removing the forward plate, Bill immediatly fedex'd new bolts & front plate-no charge.

The best thing I ever did to the car; most noticable- upgrade, cheapest, safest, and totally guaranteed for life. I have disassembled these plates twice since I installed them, once for the ZF and another for the gears. Both times just repeated Bills alignment direction and perfect!

[tomtom72]

Paul, PM sent!


Tom