Thread: '32 street rod Ford trans swap advice needed

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I have a '32 Vicky with Ford 302 and 5speed trans. I'm too old for all that shifting and want to swap trans to Automatic. It's an after market chassis w/Heidts front end. I don't know which trans to use...C-4/C-5/AOD. Concerned about the weight and the space, this is my 1st Ford experience ever. Anyone been thru this? I'm new to this site. thanks

weight won't be a very big factor but space within the confines of a custom chassis with brake cylinders and exhaust mounting olus possible floor conflick will all effect the job------luckily for you , most aftermarket frames all pretty much have had all those issues and have designs altered/modified to adapt---------I would suggest one with od but will get bulky ---------

Welcome to CHR, Dan. If it were me I would look for an AOD, or AOD-e with an aftermarket controller, given the choices. You can get one that's built for some extra HP/torque output if that's an issue, but even stock they're pretty stout. I think you'll be happiest with an overdrive unit.

I agree with Roger, get a transmission with overdrive. After driving my car 1200 miles this year, I know that I would have hated it, with a 3 speed auto and no overdrive.

Without an overdrive, the other alternative that used to be popular was to use a taller rear end ratio, like 3.0, instead of the 3.5 ratio that I chose for my car. Even that only gives you a 17% taller gear, while an overdrive is typically 30%. I set my car up to run 2100 rpm at 80 mph.

New cars have both a tall rear end ratio and overdrive, but the transmission has a lower 1st gear to produce the same overall 1st gear ratio as I have with a very tall top gear, with the overdrive 6th. Cruising rpm at 80 might be as low as 1600-1800 rpm.

the 32 ford isn't very aerodynamic and won't be at 80mph very much of the time so you'll be operating in a lower rpm range at normally attainable crz speeds which would drop that referenced 16-1800 down to 1120 rpm---------think you can crz there????????

Originally Posted by jerry clayton

the 32 ford isn't very aerodynamic and won't be at 80mph very much of the time so you'll be operating in a lower rpm range at normally attainable crz speeds which would drop that referenced 16-1800 down to 1120 rpm---------think you can crz there????????

It'll need a real short cam.

.

Before you start worrying you need to look at your rear tire diameter, rear gears and the final drive ratios of the tranny's you're considering. The AOD OD ratio is 0.67, so with a 31" tall and 3.55's you'll be turning 1805 at 70mph which should be good. What's your rear tire diameter and gear ratio?

The group of 32's we sometimes ride with seem to think their speedometers start at 80 mph. Especially on the way home from an event. Those guys rock!

Originally Posted by Scooting

The group of 32's we sometimes ride with seem to think their speedometers start at 80 mph. Especially on the way home from an event. Those guys rock!

Your not talkin bout me and sum of the gang are ya Ray ?

80 mph highway speed in a street rod!!! That doesn't give the average interstate driver much time to look at the street rod caravans as they go by. LOL! Dan Spec, you should figure what rpm you want to run the 302 at and what rear gear ratio and tire size you now have and make your trans selection from those. I would think you will need an overdrive, but you may find that you are geared for a non overdrive trans. As Tech mentioned, camshaft will influence this selection too. A 9" Ford rear sure comes in handy for these situations.

Originally Posted by Deuce4dad

80 mph highway speed in a street rod!!! That doesn't give the average interstate driver much time to look at the street rod caravans as they go by. LOL! Dan Spec, you should figure what rpm you want to run the 302 at and what rear gear ratio and tire size you now have and make your trans selection from those. I would think you will need an overdrive, but you may find that you are geared for a non overdrive trans. As Tech mentioned, camshaft will influence this selection too. A 9" Ford rear sure comes in handy for these situations.

They usually get outta yer way when they look in the rearview mirror and see this.

If you drive on I-25 in Colorado, you better be going close to 80 in the left lane, otherwise you get passed on the right. The speed limit is 75 and you'll never get a ticket for going 80. If I cruise at 70, then my rpm drops from 2100 to 1840. That's no problem at all for my 430 hp LS3, since the cam is quite mild.

1120 rpm would only be 43 mph in my car, but it will cruise at that rpm in overdrive, unless you drop it into 3rd manually, or come to a hill that puts some load on the engine. Then it would kick down automatically. I tend to put my transmission in drive, not OD, if I'm just cruising around town, but bump to OD, if I'm cruising over 50 mph. I get over 20 mpg in the city. I've never had to opportunity to drive the car on a road trip to check the highway mileage, but it should be even better.

327, turbo 350 9" rear with 3:00 and 32 1/2 tall tire = avg 21 1/2 mpg last year on a trip out to LARS and back. (with side trips 3400 miles) cruisin @ 80 -85 on the interstates in the left lane 4 sure

If the car had a 5 speed already, he'll probably be alright with another AUTO trans with an overdrive as the 5 speed was an overdrive trans as well. I'd use the AOD for simplicity and durability.

I'm very happy with the B&M converter lock up control on my 700R4.

I'd recommend including it for a 700R4, if you pick it.