1963 Gran Sport Steering Box

[Gary R.]

Hi Guys,.... I recently was honored to be asked to work on one of the original '63 Gran Sport steering boxes and figured some of you would be interested in seeing what one looks like. First I want to make clear this is not a solicitation of my services, I think everyone knows I work on vettes anyway. Secondly I will not mention my contact, car information, or location of the car. This would strictly be a review of the boxes that were custom built for these cars and unlike any other corvette box. I was the first person to work on this box since it was built. I worked on the '63 Z06's and those were stock boxes and diff's, these Gran Sports were the special ones. So if there is interest I will post some pictures and information however if there is going to be any controversy about me I won't bother. Let me know your thoughts. Thanks

[Joe R.]

Re: 1963 Gran Sport Steering Box

Hi Gary,

Congratulations, that is quite an honor!!!! I say let's see the pictures!!!

Joe

[Patrick H.]

Re: 1963 Gran Sport Steering Box

Hi Gary,

Congratulations, that is quite an honor!!!! I say let's see the pictures!!!

Joe

Agreed - I would love to see how they were built.

[Jim L.]

Re: 1963 Gran Sport Steering Box

Definitely post pictures!!!!

[Gary R.]

Re: 1963 Gran Sport Steering Box

Ok Fellows, here is the box. First off you probably know it is aluminum, one thing I didn't think to do is weight it to compare to a stock box but it is a few pounds lighter. The cover bolts are safety wired since the box will absorb heat and loosen over time. The lock ring is the same but has the holes drilled in it for the wire.

[Gary R.]

Re: 1963 Gran Sport Steering Box

The end nut is much longer but it uses the same bearings, races and balls as the stock boxes do. The bushings were the same size too but I fit custom bushings to all my boxes and did the same with this one. The end nut does not have the cast in hex the iron nuts do. You need a spanner to adjust the preload.

[Gary R.]

Re: 1963 Gran Sport Steering Box

The box is a faster ratio box then stock. Approx 3 turns compared to 4 in the stock box.

[Gary R.]

Re: 1963 Gran Sport Steering Box

The box has the same spline count and fitment as stock so the pitman arms are probably the same- I didn't get the arm or rag. The end plug is a smaller 7/8" plug that is staked in place. Removing the ball screw end bearing races was a trick since the bores are both blind- unlike a stock box. Real care has to be taken with the fine threads in the aluminum end nut too not to roll them. All in all I am very pleased with the way the box came out with the tighter lash, preload, and shaft fitment. No question in my mind the box is 100% better then it was when I first checked it. Hope you enjoy it- not a part you will see at car show that's for sure.

[Steven B.]

Re: 1963 Gran Sport Steering Box

Thanks Gary. This is great and helps us fill in the blanks on GS's! Steve

[Richard B.]

Re: 1963 Gran Sport Steering Box

Thanks Gary, very interesting

[Jim S.]

Re: 1963 Gran Sport Steering Box

Gary,
I did contact a retired Saginaw engineer that worked on recirculating ball power and manual steering gears back in the 1960's. Unfortunately, he did not recall ever working on a special Corvette Grand Sport aluminum steering gear. Two other names of engineers that could have worked on the project surfaced in our conversation. Unfortunately, those guys are deceased.

I sent the address on this posting to my retired friend. Since he is not a NCRS member, I don't know if he will be able to open it or not. I am hoping that Gary's excellent pics may trigger some of his memories around this special gear box.

BTW, I did note something from Gary's pic #2. The aluminum top cover has the date, 8-20-62 and the part number H-46970 cast on it. "H" numbers were used in the 1960's by the Saginaw Engineering Department for experimental parts in the steering gear area.

Jim

[Gary R.]

Re: 1963 Gran Sport Steering Box

Hi Jim, 8-20-62 I just turned 3 a week earlier. The box has a different date code, 12-1-62 How many of these do you think were actually made? If there were only 5 cars would there be about 10 boxes or if they were gearing up for production possibly there are more? I never saw one before. Maybe on a dusty shelf in Lansing some place???

[Jim S.]

Re: 1963 Gran Sport Steering Box

Gary,
Not on a shelf in Lansing, Michigan but possibly at Nexteer in Saginaw, Michigan (formerly Delphi Saginaw Steering and before that, Saginaw Steering Gear Division, General Motors Corp.)

I am sure that Saginaw would have produced more than the five gear boxes required for the Grand Sports. Several more would have been produced for spares; for durability testing; and for some destructive "ultimate" tests to verify the integrity of the aluminum design. I never heard of any serious approaches to manufacture an aluminum gear box for the C2/C3 Corvette.

Saginaw ceased producing manual steering gears shortly after the 1984 C4 Corvette went into production with rack and pinion steering. All of the drawings, tooling, and other manufacturing equipment was sold. At that point any remaining experimental aluminum gear parts would have been over 20 years old with little likelyhood of any need for an aluminum housing gear box.

On a similar note, Saginaw did attempt to convince Chevrolet Engineering to change from the linkage booster power steering design used on the C2/C3 Vettes to the modern recirculating ball, integral power assisted steering gear used throughout General Motors. Saginaw made a proposal around 1968 to make this change. Saginaw even had new gear housing castings produced that would fit the unique Corvette frame. Saginaw supplied the parts and Chevrolet Engineering made the installation. The installation was evaluated by Chevrolet Engineering. One of the reasons cited in rejecting the proposal was that there was not sufficient road feel with the integral power gear. Also in order to fit the integral gear to the Corvette chassis the front crossmember had to be modified for clearance. Another and probably a more important reason was that the C4 Vette was originally planned for mid to late 1970s production and would likely have a rack and pinion steering system. Overall it probably was deemed too expensive to change for only a couple years of production.

It is interesting that the linkage booster type steering system is often derided for not having sufficient road feel and is considered an "ancient" out of date power steering system. There are integral power steering gears and rack & pinion systems developed to retrofit into C2/C3 Vettes. Yet Chevrolet Engineering decided just the opposite in 1968.

Jim

[Gary R.]

Re: 1963 Gran Sport Steering Box

Jim, ..... this sounds like a job for Indiana Jones, could be the next movie with Harrison Ford looking for the missing Gran Sport parts! Very interesting notes Jim. I knew of the machinery being sold and the subsequent failure of the purchasers to machine quality parts afterwards. That was all told to me by Tom Reina years ago. The one thing I know is there is one box that is built pretty darn well now on the planet.

[Paul Y.]

Re: 1963 Gran Sport Steering Box

Thanks a million Jim Shea and Gary Ramadei for sharing this information. I find this very fascinating and am happy to have an NCRS connection with the likes of you as a sort of family.