PROJECT W-31 DONE
Part 2: Rearend Rebuild & Restoration
Part 2: Rearend rebuild and restoration
Last month we introduced you to the 1970 Olds Cutlass W-31 that Oldsmobile expert Stephen Minore has owned since 1993 (“Part 1: The Olds That Started it All Finally Gets Its Restoration,” Oct. 2018). In case you weren’t with us, here’s a recap. After buying the W-31, Minore did the “show and cruise-night thing” for a few years, but got bored with the static nature of those activities. He then modified the car into a low-12-second street/strip machine and enjoyed racing until he got that out of his sys-
tem, as well. In the late 1990s he decided to return the car to stock form. But, as we often say in these stories, life happened. The partially disassembled car was moved from garage to garage for the better part of two decades.
In 2017, Minore worked with partners Ken Garner and Allan Steinbock of Garner Customs and Restorations in Bradenton, Florida, on the restoration of a 1972 W-30 that went on to win major awards at the Muscle Car and Corvette Nationals in Chicago. While working on the W-30, the subject of Minore’s W-31 came up. Garner and Steinbock offered to help him realize his dream of restoring the car. We jumped at the chance to follow the process.
For this second installment of the W-31’s rejuvenation, Minore commissioned Florida-area Oldsmobile gurus Bruce Ponti and Rick Bedford to rebuild and restore the car’s original 12-bolt O-type rearend, which is fitted with TO-code 3:91 gears and AntiSpin (Oldsmobile’s version of Positraction).
Ponti has been into Oldsmobiles since his early teen years and throughout his 24 years of active duty in the Air Force.
His experience with Oldsmobile models ranges from A-Body 4-4-2s, G-body 4-4-2s, and Hurst/Olds all the way up to the rare, unrecognized, late-model 1991 W-41 Quad 4-4-2s, of which he currently owns two. His 1969 Cutlass convertible was recently featured on the TV show All Girls Garage for an interior upgrade. By Ponti’s own estimation, he has rebuilt and restored more than a thousand rear axle assemblies and is still counting. He loves the challenge of finding rare Olds parts.
As for Bedford, he started his Olds affair with 1966-1967 models in his mid-teens. He currently owns a 1966 F-85, a 1967 4-4-2, and a cool 1967 station wagon with some punch under the hood: a modified 425 with monster torque, 200-4R transmission, and a 3.91-geared Type O 12-bolt rearend. It’s very fun on the street, and people love it.
The men met through a mutual friend back in 1996 and have been doing Oldsmobile restorations at Bedford’s facilities ever since.
Another reason Minore went to these guys for the rearend resto is that Ponti and
“Bruce Ponti has been into Oldsmobiles since his early teen years”
his business partner, Tory DiBlasi, reproduce the Olds 12-bolt O-type-only clutches. Originally these guys were working on creating a carbon steel clutch pack to replace the organic ones in 2010 Camaros, which had major traction problems with clutches. As they were working on this project, they noticed that the late-model Chevy rear clutches had the same spline pattern and count as the older O-type Oldsmobile clutches, and at that time the supply of N.O.S. Olds clutches was dwindling.
Ponti and DiBlasi partnered about 10 years ago to launch production of steel posi clutches for 12-bolt O-type rearends and all 1971 and up GM 8.5 corporate Sspring posis. They have been supplying the kits to many of the rearend rebuilding companies in the country ever since.
Editor’s note: Garner Customs and Restorations is a sponsor of the W-31 Invitational at this year’s MCACN (November 17-18) and will unveil Minore’s W-31 at the show.
2 The original Olds clutches were broken down, most likely because of poor maintenance, age, heat, and major degradation due to use—and abuse.
1 Our starting point is the W-31’s stock 12-bolt Oldsmobile O-type posi (Anti-Spin) carrier. The 588 casting number denotes a 1967-1970 carrier with 28-spline axles and ratios ranging from 3.42 to 5.00. Notice only 10 bolts hold the ring gear to it. This is unlike the Chevy 12bolt, which actually has 12 bolts holding the ring gear to the carrier.
6 Stagger the new clutches beginning with a tab-style clutch disc, followed by a splined-style disc, and ending with a tab-style disc. Each side should have a total of seven clutch discs, four with tabs and three with splines.
7 The new clutches and shims are installed in the carrier with the axle side gears. Bruce Ponti and Rick Bedford recommend starting with a 0.075 clutch shim in each side.