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68 Coronet, slow project in Napa, CA
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Yeah, I wonder. I never liked red either, then I saw yours, another one on FB, and the little bits that keep poking through on mine, and decided I do like this particular shade of red, combined with points for being the factory color. Need to figure out best place to buy paint now as the local place switched management and suppliers, and then generally went to crap.Cool car... I wonder who's it is...
Finally got enough gunk off the transmission to get some numbers.
From a quick search it looks like this is a nothing special unit from 1971. If anyone can get more out of these numbers, I am all ears.
While I was down there with the wire brush I uncovered some numbers off the third member. Again, if they mean anything, I would like to know. Third member looks scrawnier than I remember from back when my friend would change his out every Wednesday afternoon.
From a quick search it looks like this is a nothing special unit from 1971. If anyone can get more out of these numbers, I am all ears.
While I was down there with the wire brush I uncovered some numbers off the third member. Again, if they mean anything, I would like to know. Third member looks scrawnier than I remember from back when my friend would change his out every Wednesday afternoon.
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742 = the large stem pinion... 
451Mopar
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Which Dakota Digital? The RTX non-rallye or the Charger type Rallye dash?
Those look nice, but are pricy.
Good to know. Thanks.742 = the large stem pinion...
451Mopar
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Looks like the correct axle for the car.
Not the trans, but the '71 up with the wide bushing front drum are nice because the billet drums are designed for that pump/stator support.
Not the trans, but the '71 up with the wide bushing front drum are nice because the billet drums are designed for that pump/stator support.
Funny you should ask...unless my wife reads this, then it won't be funny at all.
I started by buying the VHX-68D-STD with the black background.
1968- 70 Mopar B-Body: Coronet, Belvedere, Satellite and Road Runner
I really wanted the RTX-68D-STD-X, but it was way more money and not available at the time that I bought the VHX. One day about four weeks ago, for no good reason, I emailed Dakota Digital and asked about the RTX availability. I was told to expect about a 29 week backorder. I figured that was long enough to figure out how to justify spending that much on a dash I didn't need, so I ordered it from Summit. After a week or so they sent me an email saying that the delivery date was going to be a long way off, in case I wanted to cancel. Two weeks later they sent an email saying it was shipped and it showed up a couple of days later. It looks really nice.
1968- 70 Mopar B-Body: Coronet, Belvedere, Satellite and Road Runner
Worst thing is I am not sure I can return the VHX since it has been unpackaged and been here for several weeks. I still need to call Summit about that.
To be honest, automatic transmissions are not something I have much knowledge about. My other option is the transmission I pulled from the Winnebago (a 1976) that has the GV overdrive. One of them is likely being sent to a shop. Here are the numbers off that one:
As long as you have the real deal R/T I would be happy.
I thought all numbers matching was important to me years ago. Then I realized it doesn't mean a whole lot when I rebuilt my GTX to be the car I wanted, not how it came from the factory. I guess I was lucky to have the fender tag with my car and the serialized radiator support and trunk gutter. I know what it came with even though I didn't put it back to original.
Engine is from a 69 Charger RT and transmission is from a mid 70's truck. It's a mutt but it is my mutt. And it is a GTX, which is all I really care about.
Build it how you want it and enjoy.
Overdrive would be nice. Probably the one upgrade I should have done.
That requires a modified floor pan and trans tunnel, correct?
Not according to what I have read about Gear Vendors OD. Might have to put a dimple in the floor at worst. Also, drive shaft has to get shortened. I haven't figured out what gear ratio I want to run yet.
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Gear Vendors ratio is .78... Not a big jump... Unless your a serious racer I'd forget about 4.10 or numerically higher ratios..
4.10 x .78 = 3.19
3.91 x .78 = 3.04
3.73 x .78 = 2.90
3.55 x .78 = 2.77
3.23 v .78 = 2.51
Personally I like the 3.73, unfortunately US Gear, my preferred supplier no longer makes them...
4.10 x .78 = 3.19
3.91 x .78 = 3.04
3.73 x .78 = 2.90
3.55 x .78 = 2.77
3.23 v .78 = 2.51
Personally I like the 3.73, unfortunately US Gear, my preferred supplier no longer makes them...
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Darter6
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Did 4 cars with OD transmissions and 3.73 was my favorite.
The Chevelle I traded for this car had 3.73's with an Art Carr 200 4r and I was happy with that setup. I would actually like to go lower than 3.73's but since the GV has less of an overdrive I think I had better not. I would still like to be able to take highway trips. I would hate to think that 3.55 gears are my only real option. Back in the day those were considered practically freeway gears.
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Yup, 3.55 were considered freeway gears... But cars have have overdrive for so long that now people think their engine can't take spinning 3.200 RPM's for hours on end....
Back in the 70's I drove from Modesto to San Diego in a Challenger with 4.10's...
FWIW the 3.91 is a good gear & in O/D it becomes a 3.04 which is pretty good...
A little more info...
3.04 gear 28" tall tire (275/60-15) 75 MPH = 2750 RPM's
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Pop Quiz for extra credit, With the GV O.D, 3.91 gears, 28" diameter rear tires, what would my RPM be at say 65 mph?
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See Above, I edited my post while you were typing the one I'm responding to......
But 65 MPH = 2375 RPM's
I type slow. I think I could live with the 3.91's. Thanks for doing the math.
451Mopar
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Overdrive is nice. Axle ratio depends on several factors, mainly type of use (street or racing), the Overdrive ratio, and the tire size.
I have a LGT-700 5-speed manual OD (0.68 OD ratio) in the Convertible, and a 3.54:1 Dana 60 axle which is a nice ratio for a street car with 27" tall tires.
In Overdrive, 50 MPH is only about 1,500 RPM. The 505" stroked 440 with a mild cam has plenty of low end torque.
The 518 automatic has a 0.69 OD ratio, and I'm working to put one in another car with a 3.55:1 8-3/4 rear axle.
I have a LGT-700 5-speed manual OD (0.68 OD ratio) in the Convertible, and a 3.54:1 Dana 60 axle which is a nice ratio for a street car with 27" tall tires.
In Overdrive, 50 MPH is only about 1,500 RPM. The 505" stroked 440 with a mild cam has plenty of low end torque.
The 518 automatic has a 0.69 OD ratio, and I'm working to put one in another car with a 3.55:1 8-3/4 rear axle.
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