Which OD Trans

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WRB426

WRB426

Insane 4 Mopars
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I was wondering which "Mopar" auto OD transmission is the easiest to use? This will be for a mild 318 build. Mostly a cruiser not a racer so not looking for a beast of a transmission. Which one doesn't require a lot of electronics to run? Not worried about modding the tunnel either.
 
WRB426 said:
I was wondering which "Mopar" auto OD transmission is the easiest to use? This will be for a mild 318 build. Mostly a cruiser not a racer so not looking for a beast of a transmission. Which one doesn't require a lot of electronics to run? Not worried about modding the tunnel either.
Click to expand...
I sure like my A500 swap I did.
 
You actually don't have many choices UNLESS you don't mind chopping up the floor/ crossmember I'm referring to the upper part where the T bars mount. There's threads on about any of these

There's a thread on here about adapting the GM 200R4 or 2004R

You can put an A500/42R_ but you still need some crossmember mods

The larger 727 based A518/ R46 series needs floor mods

Then there's aftermarket like Gearvendors, I don't know who else
 
67Dart273 said:
You actually don't have many choices UNLESS you don't mind chopping up the floor/ crossmember I'm referring to the upper part where the T bars mount. There's threads on about any of these

There's a thread on here about adapting the GM 200R4 or 2004R

You can put an A500/42R_ but you still need some crossmember mods

The larger 727 based A518/ R46 series needs floor mods

Then there's aftermarket like Gearvendors, I don't know who else
Click to expand...
I'm leaning on the A500/42R. I don't mind crossmember mods.
 
The GM 200 transmission is a great choice. Close gear ratios will help a small block stay in its power band.
 
No floor chopping with the GM 2004R!! I put one in my Barracuda and I'm so happy!! 3:90 gears and runs 2200 RPM at 60 MPH>

Treblig
 
WRB426 said:
How does the OD engage? Do you have to use a switch? And what do you do about downshifting?
Click to expand...
Yes a switch in my console controls OD and lock up, I prefer this manual way but there are ways to make it switch automatic. If you need more info I would be glad to help and there are pics how I did in my build thread.
Keep it all MOPAR
 
WRB426 said:
I was wondering which "Mopar" auto OD transmission is the easiest to use? This will be for a mild 318 build. Mostly a cruiser not a racer so not looking for a beast of a transmission. Which one doesn't require a lot of electronics to run? Not worried about modding the tunnel either.
Click to expand...

So, I'm just wondering, but, would it not be easier ,cheaper and just as effective to run hiway gears and install a slightly looser TC or an A998/999 with a 2.74 low gear. IMO, for your stated use,it would be a natural.

I agree that 2200@65 is really nice.
With 275/60-15s (28s) tires, this is 2.82s@zero-slip. The closest could be either 2.94s or, 2.76s which you might already have.
(With 225/70-14s these are 26.4 tall so 2.76s are the go-to.)
The 2.74 lowgear with 11.8% more TM,will help get you going , seeming like the next size bigger rear gear.
But the clincher, to get back some take-off power,would be a 2400 or a 2800 TC, and then a good tune in the engine to take advantage if that newly released extra torque.This might add 20 or probably 30 ftlbs off the line, seeming again like 1 or 2 sizes bigger rear gear.
I'm just thinking about what you said. At zeroslip (loc-up TC);
65=2284 with 2.76/25.5s, and,
65=2293 with 2.94/28s, and
65=2153 with 2.76/28s.
I ran that combo; A999 with a 2800 and 2.76s and 27" tires for a couple of winters in my 68 Barracuda. It was a great cruiser. I also installed a semi-manual shift kit in that tranny so I could shift up/down at any speed or rpm. And headers were already in the car. And I installed a small-port intake, a small TQ and 5500rpm valve-springs. You might be thinking, that's not what you want. But check this out;
I used to floor it from a stop and get her into 3rd as quick as possible,then let the TQ moan all the way to 65mph. If you've never heard a TQ-moan for like 17 seconds, you'll be in for a treat,lol. Well ok 17 is an exaggeration.
Those 1.5" TQ primaries are great for mileage,and 2233rpm@65 (zero-slip) with 27s was great.
The A998/999 requires no extra work to install.And they are cheap to buy/cheap to build. The TC,if you choose to purchase one, will be your major expense.My 2800 did not slip all that much at 65. Until I slammed the pedal down,lol. Then the tranny kicked down and the TC buzzed up and the Rs climbed to over 3400 and I could pass anything.
BTW, the A500 has these same ratios; 2.74-1.54-1.00, but includes the .69OD.

But I get the attraction,The A500 will allow 3.91s to get nearly the same cruise rpm as 2.76s yet have 58% more first gear TM! That's a lot. I ran my 318 with 4.30s for one winter. That was plus 74% compared to 2.45x2.76. And it was awesome with that 2800.Too much for a winter motor.That was 11.78 starter gear;crazy in winter. Pretty much useless.I never ran that 4.30 behind her again,lol.Actually I did. The previous winter I ran those 4.30s with an A833O/D and a GVOD behind it but that's another story,lol
 
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I think the A500 is a pretty good choice but here are some of the details some don't realize.
1. Obviously the cross member.
2. 3/8 cooler lines from the A500 instead of 5 1/16 (best to use new 3/8 lines and change fittings at the radiator)
3. Longer speedo cable (the 80 inch works well)
4. Need to run relays for the OD and LU
5. Trans needs fused ignition 12v for the solenoids.
6. Driveline will need shortened about 3.5 inches.
7. Trans angle for the driveline angle will likely require some messing with after.
8. Being the A500 in commonly a truck trans it already has the low first gear.

My A500 uses adjustable pressure switches plumbed with cooler line to the governor port for OD and lockup so it shifts fully automatic if the switches on the shifter are both on. (OD at 50mph and lockup at 70) and of course it comes out of those two at those speeds because of the adjustable pressure switches.
With both off it won't use OD or lockup at all, and an adjustable vacuum switch for kicking it out of lockup, OD or both when intake vacuum gets low enough to trigger the adjustable vac switch.
It's all in how you wire it and what parts you use, but in the end it's worth every bit of what it takes to do it.
 
AJ/FormS said:
So, I'm just wondering, but, would it not be easier ,cheaper and just as effective to run hiway gears and install a slightly looser TC or an A998/999 with a 2.74 low gear. IMO, for your stated use,it would be a natural.

I agree that 2200@65 is really nice.
With 275/60-15s (28s) tires, this is 2.82s@zero-slip. The closest could be either 2.94s or, 2.76s which you might already have.
(With 225/70-14s these are 26.4 tall so 2.76s are the go-to.)
The 2.74 lowgear with 11.8% more TM,will help get you going , seeming like the next size bigger rear gear.
But the clincher, to get back some take-off power,would be a 2400 or a 2800 TC, and then a good tune in the engine to take advantage if that newly released extra torque.This might add 20 or probably 30 ftlbs off the line, seeming again like 1 or 2 sizes bigger rear gear.
I'm just thinking about what you said. At zeroslip (loc-up TC);
65=2284 with 2.76/25.5s, and,
65=2293 with 2.94/28s, and
65=2153 with 2.76/28s.
I ran that combo; A999 with a 2800 and 2.76s and 27" tires for a couple of winters in my 68 Barracuda. It was a great cruiser. I also installed a semi-manual shift kit in that tranny so I could shift up/down at any speed or rpm. And headers were already in the car. And I installed a small-port intake, a small TQ and 5500rpm valve-springs. You might be thinking, that's not what you want. But check this out;
I used to floor it from a stop and get her into 3rd as quick as possible,then let the TQ moan all the way to 65mph. If you've never heard a TQ-moan for like 17 seconds, you'll be in for a treat,lol. Well ok 17 is an exaggeration.
Those 1.5" TQ primaries are great for mileage,and 2233rpm@65 (zero-slip) with 27s was great.
The A998/999 requires no extra work to install.And they are cheap to buy/cheap to build. The TC,if you choose to purchase one, will be your major expense.My 2800 did not slip all that much at 65. Until I slammed the pedal down,lol. Then the tranny kicked down and the TC buzzed up and the Rs climbed to over 3400 and I could pass anything.
BTW, the A500 has these same ratios; 2.74-1.54-1.00, but includes the .69OD.

But I get the attraction,The A500 will allow 3.91s to get nearly the same cruise rpm as 2.76s yet have 58% more first gear TM! That's a lot. I ran my 318 with 4.30s for one winter. That was plus 74% compared to 2.45x2.76. And it was awesome with that 2800.Too much for a winter motor.That was 11.78 starter gear;crazy in winter. Pretty much useless.I never ran that 4.30 behind her again,lol.Actually I did. The previous winter I ran those 4.30s with an A833O/D and a GVOD behind it but that's another story,lol
Click to expand...
This is something to think about. A 904 with a low gear set and 2.76 rear gear might be a good set up. A speed analyzer puts me 72 mph at 2500 rpm with a 27" tire. I could deal with that on the highway. And it would cheaper and easier to do. Plus I might be able to afford A/C. I forgot to mention that this is a 64 Dart. A little tighter body to work with over the 67-newer a bodies. Thanks for the info.
 
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