Manual or automatic... What would you do?

[Jim P.]

I recently purchased a 67 427/400 coupe. The car is a 4-speed manual. I knew when I purchased it that the transmission was not original to the car. It is from an early 70's corvette. Later, while trouble shooting why the back-up lights were not working, I found cut wires under the dash indicative of the neutral safe switch from an automatic. I also remember my carb guy commenting that he thought that the carbs looked like they were set up for automatic at one time. I know that the primary carb has a unique part number and I will check that when I can get to the car (currently in storage).

While I would prefer a manual, research indicates that a powerglide/tri-power combination is quite unusual. It looks like of the 5600 tri-powers built in 1967 (including the all manual 435's) only about 200 were automatic. I was planning on replacing the clutch, flywheel, bellhousing, etc. with the correct parts for a 67 but now I'm having second thoughts.

Now I'm wondering if I should just put a powerglide back in. Although perhaps less desirable, it would bring the car back to its unique configuration. The build sheet is still on the tank. That will, hopefully, tell me for sure what I have. I will pull the tank this spring.

In the meantime, any opinions? What would you do?

BTW, I currently have no plans to do a full restoration or get the car judged.

Thanks, Jim

[Tom H.]

Re: Manual or automatic... What would you do?

For driving and owning, I'd prefer the manual but.................. The die hard original guy in me says restore it as it was built. I bet you'll feel better about the car. Get the tank sheet first and confirm your thoughts. Good luck with this unusual car.

[Robert E.]

Re: Manual or automatic... What would you do?

Jim, wouldn't it be easy to tell by looking at the cross member to see if was an automatic originally? I understand that automatics all had removable cross members, while manuals where welded.

Robert
41801

[Greg L.]

Re: Manual or automatic... What would you do?

Personaly I'd try and put it back to the way it was(auto or manual). Either way it will still an awesome car that anyone would be proud of to own and drive.

Won't the engine suffix tell you if the car was originaly an auto or manual? If not then do as Robert says and see if the transmission crossmember is welded to the frame(manual) or bolted(auto).

[Rich P.]

Re: Manual or automatic... What would you do?

Removable crossmembers started w/C 3's. I wish the midyears had them that would have made my life alot easier on quite a few occasions.

Rich

[Mark L.]

Re: Manual or automatic... What would you do?

Easy decision on my part. Return it to original as possible.

[Patrick H.]

Re: Manual or automatic... What would you do?

If nothing else, acquire all the parts for the conversion and have them available. Store them in a cool, dry place and if the day comes when you're ready to make it a PG car again you've got all you need.

If you're not about to sell it now, just drive it with a 4 speed if you like it that way. Why change now if you don't "have" to and you currently prefer the 4 speed?

Patrick

[Brian M.]

Re: Manual or automatic... What would you do?

I would do just what Patrick wrote.

If nothing else, acquire all the parts for the conversion and have them available. Store them in a cool, dry place and if the day comes when you're ready to make it a PG car again you've got all you need.

If you're not about to sell it now, just drive it with a 4 speed if you like it that way. Why change now if you don't "have" to and you currently prefer the 4 speed?

Patrick

[Kirk M.]

Re: Manual or automatic... What would you do?

Love my powerglide. I know that is not a popular sentiment, but I do. Nothing easier to drive. Return it to powerglide is my vote.

[John H.]

Re: Manual or automatic... What would you do?

The engine pad suffix (and the trim tag ECL code, if it's a St. Louis body and doesn't have a black interior) will tell you if it was originally a Powerglide, as will the front face of the radiator support where the Powerglide cooler was attached with Riv-nuts.

[Dennis C.]

Re: Manual or automatic... What would you do?

The engine pad suffix (and the trim tag ECL code, if it's a St. Louis body and doesn't have a black interior) will tell you if it was originally a Powerglide, as will the front face of the radiator support where the Powerglide cooler was attached with Riv-nuts.

John,

What difference would a black interior make?

Regards,

Dennis

[Joe L.]

Re: Manual or automatic... What would you do?

I recently purchased a 67 427/400 coupe. The car is a 4-speed manual. I knew when I purchased it that the transmission was not original to the car. It is from an early 70's corvette. Later, while trouble shooting why the back-up lights were not working, I found cut wires under the dash indicative of the neutral safe switch from an automatic. I also remember my carb guy commenting that he thought that the carbs looked like they were set up for automatic at one time. I know that the primary carb has a unique part number and I will check that when I can get to the car (currently in storage).

While I would prefer a manual, research indicates that a powerglide/tri-power combination is quite unusual. It looks like of the 5600 tri-powers built in 1967 (including the all manual 435's) only about 200 were automatic. I was planning on replacing the clutch, flywheel, bellhousing, etc. with the correct parts for a 67 but now I'm having second thoughts.

Now I'm wondering if I should just put a powerglide back in. Although perhaps less desirable, it would bring the car back to its unique configuration. The build sheet is still on the tank. That will, hopefully, tell me for sure what I have. I will pull the tank this spring.

In the meantime, any opinions? What would you do?

BTW, I currently have no plans to do a full restoration or get the car judged.

Thanks, Jim

Jim-----

I think the Powerglide restoration would be nice. In fact, you might find it more enjoyable to drive than you think. However, there is a problem here. The Powerglide transmission used for 1967 L-36 and L-68 Corvette applications was not the same as that used for the 300 hp small block. The torque converter was also different. The torque converter, GM #3905861, was once available in SERVICE but was discontinued in May, 1979. The transmission, GM #3895728, was NEVER available in SERVICE and was a Corvette-only piece.

There is an option here, though. You could probably use a 65-67 small block Corvette Powerglide which has been modified to "HD" standard. There are shops out there that specialize in Powerglide transmissions (primarily for racing applications and, yes, they still use them for that) and they could probably suitably modify a more easily obtained transmission for you.

[Chris E.]

Re: Manual or automatic... What would you do?

Jim,
If it were my car, I'd get all the parts together like someone else suggested and then leave it a 4 speed. That way, when you go to sell, you're appealing to BOTH groups of vette buyers (manual and auto tranny folks).
Chris

[Jim R.]

Re: Manual or automatic... What would you do?

That thought of collecting the original auto parts for the future and having it now with the 4spd sounds good to me , this also sounds like it would make you happy, thats the main thing ,whatever makes you enjoy it the most.! either way you cant go wrong.

[John H.]

Re: Manual or automatic... What would you do?

John,

What difference would a black interior make?

Regards,

Dennis

Dennis -

Black interior trim codes didn't carry an ECL code.