Automatic ****** in a Model A Ford

[CarlG]

If I didn't already have about 1.5 million invested in my Model A (lol), I'd have an automatic transmission installed. I'm only in my "early" 80's.

 

[Gene F]

If I didn't already have about 1.5 million invested in my Model A (lol), I'd have an automatic transmission installed. I'm only in my "early" 80's.

Ok, I had to giggle. I have a spreadsheet at one time on my A. Every part, nut, and bolt on it. I quit editing it some years back. I am sure I am upside down on my car too. My streetrod has a big spreadsheet, I know that!

Ya know, there may come a time for some of us older guys when a Model-A streetrod may extend our driving experience a few years more. And no I am not suggesting someone cuts up an existing good A.

 

[Dodge]

I've used the GM TH0200 behind several Dodge/Plymouth flathead 6 engines and it
makes a very drivable car with the overdrive.
Mild performance cam, 2 bl. carb and shaved head to 7-1

 

[katy]

I don't think I've ever heard of a Model A w/a "Dodge/Plymouth flathead 6 engine" in it. Got any pictures to share?

 

[40 Deluxe]

Any automatic trans. hooked to a 40 HP stock model A is going to be a significant loss of power. The engine can be souped up to increase HP but then there is always the weakest link in the frame or drivetrain that people experience. I don't know what change in mileage would occur. The advantage of having an automatic and ease of driving might outweigh the power loss for many people. Here's a list of power loss on popular transmissions published by a Car Craft article.

Powerglide - 18 hp
TH-350 - 36 hp
TH-400 - 44 hp
Ford C-6 - 55-60 hp
Ford C-4 - 28 hp
Ford FMX - 25 hp
Chrysler A904 - 25 hp
Chrysler 727 - 45 hp

So just where does the lost horsepower go? Were these numbers obtained on a dyno, or out of some magazine writer's behind?
Do these numbers apply when cruising at a steady speed on the highway or only at full throttle? At what RPM? Does the torque multiplication effect of the torque converter make up for any of the alleged horsepower loss?
An automatic trans front pump runs at about the same pressure as the engine oil pump so would require about the same power (not anywhere near what's listed here).
I say these numbers are a myth!

 

[stickshift]

The valve body takes a lot of hydraulic pressure to run and switch the clutches. That's why the powerglide uses the least HP. It only shifts once from low to high. There's also power losses due to friction and heat turning the clutch packs and planetary etc. This is why they need an external oil cooler. Losses in the torque converter slippage too. A manual transmission has power losses (gear mesh, thicker oil), just not as much as an automatic. Plenty of info on this subject on Google.