[Chiefkey]

Does the 1963 326 Automatic (tempestrorque) use the small reinforcement ring when bolting the flex-plate/ring gear to the crankshaft or not ? I didn't take mine apart so I don't know for sure what was there originally and all of the photo's I've seen only show the flex-plate bolted to the crank...no reinforcement ring. Yet I have several spare flex-plates and rings on the shelf. Seems like it would be a good idea to have the extra reinforcement for the thin metal of the flex-plate, but maybe it would interfere with installing the shaft that bolts to the crank. Can anyone tell me how it came from the factory...with or without ?
Thanks, JK

[GaryK]

What does the Chassis shop manual say?

[Chiefkey]

The manual has a lot of instructions and shows a lot of images for the manual trans flywheel set-up, but nothing helpful on the automatic flex-plate mounting.
JK

[TXSTARFIRE]

The flywheel reinforcement ring was eliminated in mid 68. If you look up the flywheel bolts there is a note that says to use 544844 when the flywheel reinforcement plate is used. The 544844 bolt is 1/2-20 x 3/4. Use 9773742 bolt without flywheel reinforcement plate. 9773742 is 1/2-20 X 5/8. My 11-73 MPC does not even list a P/N for the reinforcement plate. I would guess that Pontiac felt it was not a necessary part being that they quit using it in mid 1968. That being said, the 1963 Tempest 326 with auto trans used the 544844 bolt which I would take to mean it came with the reinforcement ring. You can probably put it together either way, just use the proper bolts.

[TXSTARFIRE]

Sorry for typo in last post. 544844 should read 544884 in all instances.

[Chiefkey]

Thanks for that excellent explanation...very informative and helpful. I'd still like to see a photo of an unmolested "326" with the flex-plate still attached. That and a winning powerball ticket are probably equal in their probability.
Thanks JK

[GaryK]

Originally Posted by Chiefkey

The manual has a lot of instructions and shows a lot of images for the manual trans flywheel set-up, but nothing helpful on the automatic flex-plate mounting.
JK

I only have a 61 & 62 Chassis shop manual, I gave away my 63, that's why I asked.

I have found that if I was looking for a picture of one thing, I had to search something else in the chassis manual to see the part I was looking for.

[Chiefkey]

Just a follow up to the question and the great info I got from TXSTARFIRE. Looking carefully in my 1969 GM Parts book, I found a definite answer on
page 0-47. Under Group# 0.666 Part # 9772675 is listed specifically and only for a 63 T/8 A.T. Plate, Flywheel Reinforcement. I guess that settles it. They may have discontinued it's use in later models, but the 1963 Tempest V-8 w/automatic trans did use a reinforcement plate ! Also as TXSTARFIRE indicated they used Part #
544884 flywheel bolts (1/2" - 20 x 3/4").

[johnta1]

Service Bulletin:





One thing is that your 63 does not use a Turbo Hydra-matic. (I don't think anyway)

[Chiefkey]

Thanks John...those Service Craftsmen News updates are a Great tool. What issue is that one in ? I only have late 62 through 63 issues I use for my Lemans.

[johnta1]

No. 3 July 1968 issue.

They are very nice to have for sure.

[Chiefkey]

John, your comment regarding the transmission type is spot on. The normal automatic transmissions, ST, TH350. and TH400 all used a flexplate mounted torque converter which would place a twisting force on the flexplate under load. The Tempestorque version of the powerglide had the torque converter mounted on a shaft behind the transaxle and was driven by a long shaft or "ropeshaft" as it is commonly referred to, that was bolted directly to the crankshaft. So, with this particular design there was never any twisting force applied to the flexplate (flywheel) except when the started motor was engaged. My guess is that the engineers were worried about metal fatigue in the thin metal flexplate when they switched from the older Jet Away / Slim-Jim design with an actual flywheel to the new Turbo-Hydramatic Transmissions. with only flexplate/ring gear set up for the new block mounted starters.
Thanks, JK