How to: T56 Magnum Quicktime bellhousing dial-in

[Mach1_Ron]

Anyone?

[T_Raven]

I've got a Quicktime bell housing to put a t56 in my 67 Firebird.

Good tips for checking parallelism and concentricity. I'll definitely do both.

I'm curious now how far off my 2 stock bell housings are in my newer TAs. My 69 is getting a 6.0 and t56 so I'll check that stock bell housing when I mate the two.

My 01 TA had a noisy input shaft bearing. I wonder if too much offset in factory parts contributed to that.

[MWFrels]

Remove the plug and the spring and set aside. Note that if you do not remove these first, you will have difficulty taking off the front cover, as the shift rail will be pulled forward as you try to remove the cover.

I have a T56 from a '06 GTO. It does not appear to have the detent mechanism in it as the OP's version.

If there is no detent in the cover am I correct in believing the cover should just slip easily off from input and shift shafts and similar when reinstalling the plate? I just had the tranny completely rebuilt by someone skilled in T56's. I myself am somewhat apprehensive as I have never worked on a manual shift box yet alone one as advanced as this T56 seems to be.

Comments will be appreciated.

Mike

[Oregon]

I attempted to check parallel alignment today on a quicktime bell housing. I attached the block plate to the bell housing then properly torqued the bell housing to the block. The runout seems worse than most people seem to be seeing. Am I doing something wrong?

I made sure to set zero at the largest positive number. Once zero was set I spun the crank 3 times to make sure I hit zero at the set point to verify there was no play.

Here are the measurements:

[andrewb70]

Is there paint on the bell housing where it mates with the block?

Andrew

[Oregon]

There is the black coating that comes on the bell housing. I'm not sure if it's paint or powder. It doesn't seem to have any imperfections that would cause the readings to be that far off.

After looking more carefully, I did notice that the 2 bottom most bolts that hold the block plate to the bell housing were interfering with the rear of my oil pan....

I'm going to pull the 2 bolts and see if they were causing a slight bow out at the bottom of the bell.

[Oregon]

Ok. I removed the bottom 2 bolts and re-measured. The numbers improved quite a bit but I'm still seeing a spot on the left on the floating portion that is pretty far out.




I laid a straight edge across the bell housing face where the floating portion is. This section is clearly not in alignment with the rest of the face.


Should I ignore this section when aligning? Are the rest of my numbers reasonable enough to start shimming?

Thanks.

[andrewb70]

....

Should I ignore this section when aligning? Are the rest of my numbers reasonable enough to start shimming?

Thanks.

Yes, I would ignore it.

Andrew

[JodysTransmissions]

You must remove the front bearing plate of your T56, then mount the plate to your bellhousing. Then you index the input shaft bearing bore of the front plate.

[Oregon]

Jody,

Are you saying to do parallel alignment checks with the T56 bearing plate in-place?

[JodysTransmissions]

Jody,

Are you saying to do parallel alignment checks with the T56 bearing plate in-place?

Yes, both the parallel and concentric alignment checks are done with the front plate installed onto the bellhousing. Your method of measuring is only indexing the bellhousing to the block. There are another set of dowel pins and alignment issues when you locate the T56 to the bellhousing.

User and our friend "mrennie" has started this thread with many pictures, check out page one.

[Oregon]

I saw some of your earlier pictures showing a gauge against the bellhousing face so I made an incorrect assumption.

I'll throw the plate on and try again.

Thanks Jody.

[JodysTransmissions]

Great job Oregon, I like to see guys take the extra steps as you are doing. Your reward will be a smooth shifting T56.

[Oregon]

OK. I bolted on the bearing plate and measured against the top of the bearing race like 72BBSwinger did in post #52. The farthest out I'm seeing is .003". Time to get some shims and dial it in. Thanks again for all the help.

[JodysTransmissions]

I always remove the input shaft bearing race and shim to measure the machined surface of the front plate. Removing the input shaft bearing race and shim should also give you another set of alignment numbers.

[Oregon]

I pulled the race and remeasured the machined surface on the front plate.

Set zero at the highest positive reading and after sweeping around, the largest number I saw was -.0016".

Does this reading nececitate a shim or is anything under the .002" TIR spec good to go?

I suppose I could order up some .001" shim and try to REALLY dial it, but I haven't been able to find slotted shim stock sold piece meal and I'd rather not have to by a whole box of the stuff.

[JodysTransmissions]

You will probably need around .005" shims to get your parallel in spec. Remember, you are measuring very close to the center and adding .001" shim will not change your readings. My tolerance target runout is .0005" TIR for the T56 parallel alignment.

I can supply you with slotted shims as I am the guy that buys each decimal size in the box of 20.

Here is a great tip for you guys, buy a couple cheap feeler gauges from your local auto supply store to mock up the parallel alignment. Then you can buy just the slotted shim sizes you need.

Another tip when adding shims; never change your new zero location that was your most positive reading as you add shims.

Post your new parallel alignment numbers with the race and shim removed, then we'll help walk everyone through this together. Keep up the good work!

[Oregon]

Here are the new measurements. Full disclosure...my gauge only has .001" resolution so anything finer than that is a "best guess".

[JodysTransmissions]

Here are the new measurements. Full disclosure...my gauge only has .001" resolution so anything finer than that is a "best guess".

Your numbers just don't seem right, you have all negative readings except one spot. Please remove your bellhousing and double check the block and bellhousing mating surfaces for paint, dirt, or nicks etc.

I use a countersink bit and chamfer all holes for the bellhousing, scattersheild plate, and anything else a bolt passes through to make sure everything sits flat and true.

[Vin442]

Good Morning All, what an awesome thread! Fortunately, or unfortunately actually, I read this because of multiple issues I have had with my T-56 installation in my 68 Cutlass. We had dialed in the QuickTime Bellhousing to almost 0.001 to the crank centerline (using the "normal way" and figured I was set. However, after only 500 miles, lots of noise, sh$&@;()tity shifting and possibly blowing my motor for the second time (it happened late last night so I can't say for sure what actually occurred) I decided to reinvestigate the alignment issue I think I may have. Looking at the thread, I did NOT align the way it has been posted here. I hope that the trans and engine are not damaged requiring rebuilds. I will post pics of everything once I get the car towed home and take it apart AGAIN. Wish me luck, Vin