[MOJO Catalina]

OK guys, I know I'm the 10,000th person to ask this, but what type/year trans is the best and easist conversion for a '63 Grand Prix?

I just bought a running project car, fixed the emergency brake and drove it down the block. The trans is slipperier than a nighcrawler covered in worm sh*t..

I fear that "Old Jim" may have Alzheimers and is forgetting when to shift.

This car hasn't seen full time action since 1987 but there are receipts for other maintenance that indicate the previuos owner took pretty good care of the car.

Might be that the slipping trans caused him to give it up but who knows??

Any chance this trans might "heal" itself with some use? (LOLOLOLOL!!)

I'm working on fixing the drum brakes this week and plan to take it to the highway ASAP to check the trans.

Should I change the fluid first? It looks OK now...

I'm predicting the worst so trans swap will probably have to happen and I want to keep the console and not have to carve up the floor.

[Stuart]

Originally Posted by MOJO Catalina

OK guys, I know I'm the 10,000th person to ask this, but what type/year trans is the best and easist conversion for a '63 Grand Prix?

And of course there are 10,000 previous discussions on this topic that you can find if you do a search.

The simplest thing would be to get your existing transmission rebuilt, but that will be expensive, there aren't that many people around who know how to work on them, and it will still be a slim jim.

The biggest problem is your car has the starter bolted to the transmission, while later cars had the starter bolted to the engine block. As a result if you swap in a later transmission there's no place to fasten the starter to unless you buy an adapter plate from Bendtsen's or Wilcap.

Once that is sorted out, then you have to get the transmission to fit under the car. Assuming you use a TH400, you'll at least have to massage the transmission tunnel with a hammer to get it to fit.

[Keith Seymore]

Just did a TH400 swap a year ago (with a Bendsten's adapter plate) and I'm pretty happy with it.

In hindsight, an overdrive would be a nice feature and I hear a 200R4 (?) fits in the tunnel without beating it up.

K

[Deadhead]

For about 2 grand to 2500, I converted my '63 Slim Jim car to a 4 speed. (Bought the majority of the stuff all in one batch for $1200, then $300 for a driveshaft, $350 for clutch, another $300 in Misc. like the B/U switch stuff. It will cost a little more to do yours since you will need the console, but I really think for what it costs to do any conversion this is the way to go. Huge bang for the buck comparison.

[MOJO Catalina]

OK, but the research thing is so impersonal and sometimes people have new, fresh ideas... What's this 700-something trans and how do I get one?

I'd love to convert it to a 4 speed and have been looking for a 4 door Catalina with a 3 on the tree as a parts car but those are just as rare as a decent Wagon.

Attached is a photo of what an $850 '63 grand prix looks like.
The engine runs great, floors are solid except the trunk (plywood now) seats are in great shape, but that pesky pot metal has more blisters and burrs than crab legs...

[BigAquaBonney]

Check this guy out. Extremely knowledgable. Can set the whole exchange up. He likes 700R4's

http://www.transmissionadapters.com/

[poison heart]

The GP looks good to me! Nice find

Can't you do an early hydramatic conversion? Like the Bonnevilles and Star Chiefs had?

You could do the 4 speed swap, that's what I would do...

You could do the transmission adapter and run a 700R4 and it probably wouldn't be that hard or cost too much

[MOJO Catalina]

http://www.transmissionadapters.com/

That's a great link. I'll file that one as a possibility.

I don't think the 4 speed Super Hydramatic from the 'Chief and Bonny fit under the tunnel without a hack job.
I do have a '63 Bonneville parts car that I could torch the floor out of.
Has anyone done this? Does the shifter and console still mate OK to the SH? I'd imagine there would be some carving down of the console porch to accomodate the relandscaping of the floor.. I have the SH in my '60 Catalina and '63 Bonnevertible and am fine with those. It would be great to be able to use what I alerady have...

Would the drive shaft from the GP or Bonne be reused or would I have to have one made? Are the SH and RH trans's the same length?

[poison heart]

Oh, screw that!

4 speed it then

[Deadhead]

64CATDROPTOP had some posts about this and the floor shifter configuration. There are differences there.

The other conversion I considered most seriously was the SH. Since you already have that that would be the way to go. There are other posts about this conversion as well. I don't think it is necessary to redo the entire floor. It is just the rear section of the Trans that may need some floor messaging to accommodate. You will also likely need to have a driveshaft made and will have to fiddle with the linkage, but if you have a decent trans already in a car with all those parts on it... That sounds like a good project to me.

That is a great looking car for $850. That guy in the Pic thinks so too huh?

[BigAquaBonney]

The linkages for a console 4 sp Super Hydromatic/Jet-Away are extremely difficult to find. The linkage is completely different than the linkage in the Roto-Hydromatic Catalina's and GP's.There were only so many console car Bonnevilles and Start Chiefs (?) with the big tranny. My '64 Bonneville Convert is a factory bucket/console car. It took about two years to find the linkage when I put the original rebuilt drivetrain back in in. (I bought the car with a 400/400 in it, and the original engine rebuilt on a stand, and the not rebuilt tranny in the trunk)

[poison heart]

Good point, I have never seen a 63/64 Bonnie or Star Chief console car.

[MOJO Catalina]

(Besides propping up Old Jim) Anyone know if there's a trans choice that will not involve cutting a drive shaft or any linkage modification?

I know some of y'all are bored with the subject but I do appreciate you fellas taking the time to lend opinions and tech support.

Below are a few more photos of what the car looks like today.
I've rerouted the output of the center AC duct so I can mount the accessory Oil and Temp gauges and changed the snarled front bumper to a straighter one, but it's the way I got it otherwise.

[poison heart]

63 Cat? 60 cat? 58 buick? and now a 63 GP? You lucky bastard!

That GP is a steal!

What about a TH350/400 or 700r4 swap? I don't think any trans is the same size or the same linkage as the slim jim so you're probably going to have to modify something. I still say 4 speed it...

[MOJO Catalina]

Sorry to dissappoint you, but it's a Caddy.

[MOJO Catalina]

Yeah, your probably right about the 4 speed conversion. It's probably the only car I have that I'll consider doing that to since it has bucket seats already. I did a 4 speed conversion to my '62 Impala convertible 25 years ago but parts were alot easier to come by for that car back then. I suppose I can somehow box out the console to encompass the shifter using pieces of another console... Should be interesting... Oh, and that's a Bonneville in the garage..

[MOJO Catalina]

Photo taken Thanksgiving day.

[Engine-Ear]

Love the Caddy! ...and the lady in the Caddy is easy on the eyes, too!

But back to the topic question-you may want to PM SteveP about parts (pan gasket/filter kit, seals, etc.) for that Slim-Jim.

As for the shift point improvements, I was able to get a couple of my SJ-equipped '62s to shift much better by experimenting with the TV (throttle valve) rod that connects to the carb linkage.

If interested, I have a rebuilt, never-installed SJ trans that I won't be using.

[poison heart]

Hey the photos barely showed any, I was close!

[Scott M]

What is the original color on the GP?