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Pancho
09-30-2012, 11:48 AM
The automatic transmission on my 53 hardtop won't go into third. It needs work but I'm more inclined to put in a GM one. I know this has been hashed out here on the forum many times and have read many of the discussions. There are two things I want to ask about. Do I need to modify the firewall to accommodate the 700 r4? Do I need to change the gearing in the rear end, stock gearing but unsure exactly what it is, to work better with the transmission?

PackardV8
09-30-2012, 01:09 PM
No and No.

And yes, it will transform the car for the better; all you need to do is come up with the $2500 to do it correctly. This figure was some years back, so your costs may vary.

And yes sometimes the CASO way can save money; sometimes it's just more work. All the discussion to which you referred has some adherents of just putting in a Pik'n Pull special. One such adventure with which I've had correspondence hasn't gone well.

The CASO went to several Pik'n Pulls to find a non-electric 700R4, wrestled it out, took it home and got it installed. The tranny didn't work at all. The new fluid having gone through the bad tranny looked dark and gritty. Drained the now contaminated tranny fluid, pulling everything apart and took it back to the yard, pulled the pans from several transmissions to find one which didn't look completely filled with tar, then doing a second install. This one was from a higher-revving engine and required a change of governors to get the shift points close.

Then, even with the help of a competent GM shadetree, they couldn't fab a TV cable bracket on the Stromberg carb which would have the correct geometry. Despite the fact I had warned/recommended they pay BowTieOverdrives the big bucks for their kit, I became an enabler, took pity and loaned them my bracket to copy and my instructions and gauge to do the setup properly.

Your results may vary.

jack vines

studegary
09-30-2012, 01:29 PM
Maybe a basic question, but are you sure that it is not going into third? For 1953 ATs, in drive the transmission starts in second and then shifts to third. Then the torque convertor locks up (no change in gearing). For the later 250M, the transmission starts in first and then shifts to second and then third before torque convertor lock up.

Have you tried the most basic things, like changing the fluid in the transmission and torque convertor and made sure that it is at the proper level? To check, run the transmission through the gears with the fluid warmed up, check with the engine running and transmission in "L". It takes more than eight quarts. Be sure that it is full, but do not overfill.

You probably have a 3.54:1 ratio, but you would have to check to be sure. If it is in that range, I would not change it for an OD transmission.

Pancho
09-30-2012, 06:09 PM
Thanks Gary and Jack. I'm not a CASO but I'm also not rich. I try to be practical and spend money on things that make sense. I know a guy who builds great transmissions and he's built a couple for me before. I'll have him make the modifications to the 700r4. I did forget to mention the transmission in my car is an upgraded one from a 55. It might need some minor work to get it going but I'd rather put my money in a better setup.
Good to know it will hook up without mods to the body and rear end. I plan on fabricating a new center section to add rigidity and incorporate a Trans mount into it.
Thanks again for the answers and help!
Frank

Pancho
09-30-2012, 07:33 PM
Hey Jack,
Just looked up the kit for the Rochester two barrel carb and it's $170. Doesn't seem outrageous to get the car on the road and its all there. Don't need to make anything just put it on. I wonder if it'll work if I change my carb set up to 2x2 or 2x3? I'll have to contact them when it comes time.
Thanks again!
Frank

junior
09-30-2012, 08:18 PM
ok, I may be wrong on this one, but as I recall, the 200r4 is a smaller trans. than the 700r4, is plenty strong for the Stude, and doesn`t require a tv cable...maybe check into thisÉ (sorry, that funny symbol is supposed to be a question mark, by my keyboard is stuck in French-mode and can`t get it to go back to English mode.) Regards, Junior.

41 Frank
09-30-2012, 10:08 PM
While it is true the 200 4R is a smaller trans than a 700 R-4 they both do use a TV cable. I have a 200 4-R in my 41 Champion behind an R-2. I do also manufacture and sell the adapter to convert to a GM trans. Shameless plug!

ok, I may be wrong on this one, but as I recall, the 200r4 is a smaller trans. than the 700r4, is plenty strong for the Stude, and doesn`t require a tv cable...maybe check into thisÉ (sorry, that funny symbol is supposed to be a question mark, by my keyboard is stuck in French-mode and can`t get it to go back to English mode.) Regards, Junior.

Pancho
09-30-2012, 10:27 PM
While it is true the 200 4R is a smaller trans than a 700 R-4 they both do use a TV cable. I have a 200 4-R in my 41 Champion behind an R-2. I do also manufacture and sell the adapter to convert to a GM trans. Shameless plug!
Do you also sell the bracket to hook up the TV cable to a Rochester setup? I know Bowtie makes it but I'd rather do business with the Stude world.
No offense to the 200, I just have more faith in its big brother. It's a familiar transmission I have torn down and rebuilt.
I do like to hear your opinions all the same!
Thanks guys.
Frank

41 Frank
10-01-2012, 09:35 AM
No we don't sell the TV cable bracket Frank, sorry. Best to purchase it from Bowtie or one of the other suppliers. I have a Bowtie setup on my car and also use their converter lockup control.

Do you also sell the bracket to hook up the TV cable to a Rochester setup? I know Bowtie makes it but I'd rather do business with the Stude world.
No offense to the 200, I just have more faith in its big brother. It's a familiar transmission I have torn down and rebuilt.
I do like to hear your opinions all the same!
Thanks guys.
Frank

PackardV8
10-01-2012, 11:10 AM
Pancho, you keep mentioning "Rochester" carburetor. Has your Studebaker been converted? AFAIK, most '53s would have a Stromberg.

jack vines

wittsend
10-02-2012, 01:44 PM
I'm one of those CASO, "Pick A Part" people (and no offense taken). I looked for well over a year for a desirable transmission. Eventually I found a '92, 700R4 (later the better before going electronic) at the Sun Valley, CA. Pick A Part. It was $70 including the convertor at their 50% off sale. I sent back a Ford C-4 from my Turbo Pinto project as a core (otherwise add $18). Patience is a real virtue. This transmission was exceptionally clean compared to the engine with a silver painted case indicating it was likely recently rebuilt. Pulling the pan I found bright red fluid and very minimal material in the pan.

I installed mine in a '64 Daytona (4 dr.) w/350 Chevy engine. I don't know how that floorpan differs from yours. I thought clearance might be an issue along the backbone of the transmission. With hammer in hand I followed the transmission form down the center of the transmission tunnel. In retrospect it was unnecessary but not wanting to constantly hoist the transmission I wanted to be "safe and not sorry." The "batwing" needed about half its rearward metal notched out in the center. The crossmember only needed slot elongation. Note that there are three tailshaft housings for a 700R4. Get the one that has a mount similar to the Studebaker. You will need to deal with the driveshaft. The Daytona had a one piece and I found a correct sized replacement from a '76 Buick Skylark (4 dr.). A method of hooking up the shifter must be found. I simply went to a floor mount from a '95 Camaro. And, yes, there is the dreaded TV Cable. A trans cooler is recommended. You also need to control the overdrive lockup. I did mine with a few relays for about $5.

I have 1 st, 2nd, and reverse for sure. A cracked windshield keeps the car off the road so full testing has not been completed. But I'm hopeful that 3rd and 4th are also functional. I have all of $150 in the fully installed conversion and a boatload of hours (the CASO - way). If your a financial "tweener" you might buy a core cheaply and do all the fabrication - then send it out for a rebuild.

Lastly, as to ratios, the 700R4 has a rather low 3.06 1st gear and a substantial gap between 1st and 2nd. Depending on your existing ratios the 700R4 might seem too low in 1st. On the other end the .70 overdrive becomes a factor. My calculations with my 3.07 rear gears has me turning about 1,700 RPM at 65 MPH. Just as a reference that factors out to 2.15 gears with a standard 1:1 ratio of the typical top gear in a non-overdrive transmission. Factored in are the 225-60-16 tires I'm using.

Tom