AOD to flathead

[Ol' Ron]

I stan corrected then. I did run a stock flathead in front of a C4 and it seemed to operat wuite well. I ran a Merc o matic in my truck for several years with a 3.30 rear. that worked great. guess I'll have to add that to my stupid factor.

[Ardun]

3:55 is debatable as a good ratio for and AOD without a kit. Check ratio before running. Putting in a kit afterwards is so messy, I know!

[40 Deluxe]

Originally Posted by Ol' Ron

I stan corrected then. I did run a stock flathead in front of a C4 and it seemed to operat wuite well. I ran a Merc o matic in my truck for several years with a 3.30 rear. that worked great. guess I'll have to add that to my stupid factor.

Don't sell yourself short, Ron! I've read your book and did not see any evidence of any stupid factor!
Interesting thought on your MercOMatic: The planetary gearset design is known as the "Ravigneaux" design (designed by a Frenchman, as you can guess by the name!). The AOD uses the exact same design so any power loss would be the same as your MercOMatic/FordOMatic.

[Ol' Ron]

Thanks, proof that you can learn sumpin every day. It just requires an open mind. AS for the stuip factor, everybody has one. Mine runs in the 2-3 range, but every once in a while hits the big 10. I'm often reminded of this by ny daughter,
Gramps

[flatford8]

Originally Posted by Ol' Ron

Thanks, proof that you can learn sumpin every day. It just requires an open mind. AS for the stuip factor, everybody has one. Mine runs in the 2-3 range, but every once in a while hits the big 10. I'm often reminded of this by ny daughter,
Gramps

When my boys were teenagers they thought they were smarter than me, now that ther’re in their early 30’s...... they prove it everyday!!!!.... Mark

[Rocket455]

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Thanks for all the input, guys. I'll be sure to get professional help before driving the car. The thing is in now. I'm trying to figure out what to use for a crossmember. I'll get the rear end done and I think I need to check the angle of the driveshaft. And then also get a driveshaft.


I'll update you guys as I go. Bare with me though. This car has been sitting for 50 years. Front end just about done, engine and trans are in, still need most of the engine accessories, need to go through rearend, rear brakes, fuel system, all related lines and linkages need to be replaced. Took out the old brittle falling apart wiring and need to replace all of it. I'm in the Army and have had a lot of down time lately so made a lot of progress. But it's starting to ramp back up. Hopefully, I can keep the momentum going. I'm starting realize how much work keeps me from doing all the fun stuff I want to do.

[1948F-1Pickup]

If you use a "constant pressure" valve body in the AOD you will eliminate the chance of messing up the transmission from an improperly adjusted or failed TV cable setup.
Here's but one place that sells just such an item....

http://www.silverfoxtrans.com/valveBodies.html

[JSeery]

But keep in mind:

"*Please note this valve body does not eliminate the use of the TV cable. The cable MUST STILL BE USED and functioning properly so the valve body can receive feedback from throttle position to maintain shift points. No one can make the claim it will eliminate the cable and still shift full-auto."

[Marvin/TN]

I am putting an automatic in my 46 coupe, Kinda hard to drive a str shift with one leg.

[rotorwrench]

Folks that have had a TV cable break would likely want the constant pressure valve body modification. Cable breakage can happen so it pays to get as well made a set up as possible. Having the extra pressure all the time makes the transmission run warmer if the car sets and idles very long. It can also lead to problems with governor function so folks have to start changing governor valves.

This link touches on the subject. https://www.stangfix.com/threads/tci...opinions.5455/

The throttle valve position tells the transmission that the engine is at idle for base line. It still has to have pressure modulation to get the shift points correctly. The governor also helps with the shift points. I imagine that the CP valve body is going to control more from the governor but that makes it hard to change or fine tune the shift characteristics. The cable also has to be there for kick down. I'd much rather have just the cable myself. The OD lockout feature on some of the valve body mods might be handy if a person puts one in a pickup and starts pulling trailers with it. This would stop the constant shifting from OD to 3rd every time you encounter a hill.

The one thing an AOD transmission should have is a transmission fluid temperature gauge. This would tell a person if something was wrong with a TV cable while driving long distance. It would be that or a pressure gauge.

[Ardun]

Agree on constant pressure valve body.

[Ol' Ron]

Can you put a 700R4 behind a flathead>>

[Rocket455]

Originally Posted by Ol' Ron

Can you put a 700R4 behind a flathead>>

When I was looking at what trans to use I saw this adapter. It's a bit pricey.


https://transmissionadapters.com/pro...hevy-automatic


It doesn't specify which chevy trans. But I think any TH350, TH400, 700r4 or 200r4 would work the same. Maybe even a powerglide...not sure about that one though.
I've always been an Oldsmobile guy before I inherited this shoebox from my grandfather. I know that the BOP trans bolt pattern transmissions are the exact same as chevy bolt pattern transmissions save for the bolt patterns. And in my experience the 700r4 is basically a TH400 with an overdrive. The TH400/700r4 is longer than the TH350/200r4 but bolts up the same.