When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I learned a fun fact while working on restoring a 1969 rolling chassis this summer that not all 1968 and 1969 Corvettes came with Posi-traction on the car. In fact, in 1968 and 1969, posi-traction was an option. Option was called G81 and it was used for all axle ratios. In 1968 there were 28,566 cars built, 27,008 of them with posi-traction, 1,558 without posi traction or about 5.5% of the cars. You had a 95% chance of getting a posi in 1968.
In 1969 there were 38,762 cars manufactured, of which 36,965 had the G81 positraction option. That means that 1,797 cars, or about 4.6% of all 69's did not have that option. Of note, 1,661 cars in 1969 had the F-41 option which was called the "special front and rear suspension" which we call the Gymkhana today.
We have no way of knowing how many of the original 1968 or 1969 cars are still on the road today but it does make me wonder if there could be more than a few of them out there that have the non-posi units in them, and their owners don't know they are not posi-units.
Would be good to hear from one or more of them to know how the car performs and rides with a non posi unit in it. That car, in my opinion, is more rare than many of the coveted options which make a car rare today including the L-46 engine.
If you have a non posi-traction 1968 of 1969 and wouldn't mind sharing 1) How do you know it is a non-posi unit; 2) When did you discover it was non-posi; 3) What is the gear ratio of your non-posi unit; and 3) how does it perform? I for one would love to know.
By the way, the non-posi unit I have here is a 3.36 ratio non-posi unit and it operates in a fascinating way. I may have it restored as a museum piece because no one would want it in their car today believing it to be inferior to the posi-traction of the 69 Corvette.
True depending on transmission choice. The TH400 required Posi. Some of the 4 speed combinations may have required it.
Thanks Mike. I love doing research and these cars fascinate me with all the variations that were possible. I suspect some owners may have swapped out the non posi for a posi unit on the cars too making it less likely all of them are still in their cars today. I know one is sitting in my garage now so there is one less on the road now.
Here is some paperwork on a 69 that was ordered without a posi rear. Also, if you notice, no 4sp or automatic was ordered so that means it has the dreaded 3sp manual....and no soft-ray tinted glass which is another option almost very car received. Add to that its green and that pretty much probably makes it the least desirable 69 corvette to come out of St. Louis.....the only additional option the buyer ordered was a radio. The head restraints were mandatory.
Here is some paperwork on a 69 that was ordered without a posi rear. Also, if you notice, no 4sp or automatic was ordered so that means it has the dreaded 3sp manual....and no soft-ray tinted glass which is another option almost very car received. Add to that its green and that pretty much probably makes it the least desirable 69 corvette to come out of St. Louis.....the only additional option the buyer ordered was a radio. The head restraints were mandatory.
Wow, good documentation. I wonder how much of it has changed during its life? Fascinating information. Means no a/c too, correct?
Would have value as rare, even if not desired now.
Thanks for sharing.
David
I have run into a few C2 and C3 non-posi Corvettes. Typically these cars have zero options. The '69 I saw was black/black convertible 3-speed. Probably a dealer ordered a no option car so they can advertise; "Corvettes starting at $4,438"
Wow, good documentation. I wonder how much of it has changed during its life? Fascinating information. Means no a/c too, correct?
Would have value as rare, even if not desired now.
Thanks for sharing.
David
I have run into a few C2 and C3 non-posi Corvettes. Typically these cars have zero options. The '69 I saw was black/black convertible 3-speed. Probably a dealer ordered a no option car so they can advertise; "Corvettes starting at $4,438"
That's what I would think also.
However, the green one I posted was actually ordered by a customer. I have the actual dealer wholesale order form from that car with the original owners name along with all kinds of other paperwork connected to the car. Its possible it was used as some type of company car. I have another set of documentation for a low optioned car that was used for that purpose.
However, the green one I posted was actually ordered by a customer. I have the actual dealer wholesale order form from that car with the original owners name along with all kinds of other paperwork connected to the car. Its possible it was used as some type of company car. I have another set of documentation for a low optioned car that was used for that purpose.
In the case of the car I saw, I believe if the dealership did not specify, Corvettes came from the factory black/black.
Thank you for sharing- I love that stuff!
Black/Black, no posi, no air, three speed automatic, no power steering, no radio, now that would be an interesting and (forgive the term) 'rare' car. We typically think of rare as highly sought and desirable, but there are clearly exceptions. Thanks to all for sharing, good information.
David
Black/Black, no posi, no air, three speed automatic, no power steering, no radio, now that would be an interesting and (forgive the term) 'rare' car. We typically think of rare as highly sought and desirable, but there are clearly exceptions. Thanks to all for sharing, good information.
David
As the post below reminds us, rare isn't necessarily desirable but I agree that it's fascinating. I've always been interested in the heavy duty brake option. I know the caliper pitons had some sort of heat barrier and two pins instead of one to hold in the pads, but I really have no idea if it would make any noticeable difference. In most mid 70's cars, they couldn't get out of their own way so posi probably made no difference either.
Originally Posted by Dynra Rockets
Don't confuse rare with valuable. Non-posi cars are not loved. Just like 3-speed cars are rare, they are also worth less.
Totally agree but there are some interesting exceptions like an original radio delete plate. Not useful or desirable on its own but lends credibility to the thousands of L-88's out there. I used to wonder how many fenders were drilled with three holes on fake LT-1's.
My '69 is a non-posi, which surprised me when I verified the casting number on the differential (AK code).
I've only lit up the tires a couple of times, and do notice (or at least believe) that I can feel only the left wheel break free.
Also a minimally optioned coupe: manual brakes and steering, no air, no power windows, and a 350/300 original engine with a factory 4-speed (thank goodness for that!)
Don't know that I'd ever find myself in a situation where I'd wish I had posi in this car. Unless I was stuck in the mud in Alabama, where everybody knows: one tire just spins, and the other does nuthin'!
Did you say "Yutes"?
My '69 is a non-posi, which surprised me when I verified the casting number on the differential (AK code).
I've only lit up the tires a couple of times, and do notice (or at least believe) that I can feel only the left wheel break free.
Also a minimally optioned coupe: manual brakes and steering, no air, no power windows, and a 350/300 original engine with a factory 4-speed (thank goodness for that!)
Don't know that I'd ever find myself in a situation where I'd wish I had posi in this car. Unless I was stuck in the mud in Alabama, where everybody knows: one tire just spins, and the other does nuthin'!
Did you say "Yutes"?
Best movie ever. Does the defenses case hold water? Are you sure?
My 69' L-46 Coupe came from the factory with the M-21 Close Ratio 4-Speed and a 3.70 open end diff.
I figured it out when I crawled underneath to check the numbers on the drive train. The tank sticker also confirmed it.
Even though someone put a posi tag on the filler plug, the number was for a non-posi.
Spinning the rear wheels while they were off the ground confirmed 100% it was an open end.
Driving the car, you really can't tell the difference unless you lose traction on the one wheel or try to pull a holeshot and you only get one stripe ;-)
I've since had the diff rebuilt and had a posi carrier installed with the original 3.70 gears.
I did keep the original open carrier-
The guy rebuilding the diff said the open rear is probably what kept the original gears in such good shape. Not as much stress as with a posi I guess.
I have an open rear end, at least that is what the guy's restoring the car said. I have not had enough time to look into this or work on my 69 this year due to the house addition which is almost complete but for some reason the wife keeps adding things to the todo list. Why the powder room on the opposite side of the house now needs to be re-done is a mystery to me one that I am not going to try to figure out.
The Rear end is about the only original component for the drive train left.
09-29-2017, 06:58 AM
1968 - 1969 Owners, Are You Posi-Tive?
