Overdrive Options

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LJS30

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Well guys I took my car out on the highway for a forty mile round trip excursion and man it ran smooth. It was amazing how much torque a mild 318 build will add to a fun highway driving experience. However I do wish this ride had an overdrive. The low RPM's and increased mileage must be awesome. For you guys with OD's what are my options?
 
Just 200R4 where to buy it??? How dose it bolt up to a small block; that is a chevy trans right.....
 
You must consider the rear gear you are currently running?

Ex: 3.21 with the 200R4's .67 od gives you a 2.15 in 4th. Might be a little lazy even at highway speeds.

With the above ^^^^^^^^^and a 26" tire, you'd be about 1700 @ 60mph.
 
Just 200R4 where to buy it??? How dose it bolt up to a small block; that is a chevy trans right.....

Yes it's a GM trans (it has both the BOP and Chevy bolt pattern) and was used as the only transmission from the Buick Grand National.
 
iam thinking of what it would cost to find a 200r4 core, have it built up to take some abuse, new convertor, brackets and linkage for the cable, new shifter because your original floor shifter wont work, then any floor mods that maybe required, and a custom built crossmember. oh, i forgot the adapter kit. hmmm. gearvendors is starting to look pretty good. no cutting, just bolt it in and wire it up. i would mention shortening the drive shaft but you have to do that anyways. jmo.
 
I did see somewhere that the GV does not need any cutting. Also seen someone mention that there is a small spot on the floor that needs a bit of hammering to get it to fit. Think like anything else every ones car is going to be a bit different. You will also get some benefit if a lock up convertor were used.....especially in cases where your stall is up there a bit. There is a member here that sells GV units that no doubt will be along some time soon to argue with anybody that has anything negative to say about it so......
 
I have a gv unit in a non mopar for the last ten plus years never had a problem with it. The only issue I had was they tod me minor floor modification.

If you consider raising about a four inch section of the tunnel up two inches. Then yes it was minor.

Mine is behind a 4spd.
 
iam thinking of what it would cost to find a 200r4 core, have it built up to take some abuse, new convertor, brackets and linkage for the cable, new shifter because your original floor shifter wont work, then any floor mods that maybe required, and a custom built crossmember. oh, i forgot the adapter kit. hmmm. gearvendors is starting to look pretty good. no cutting, just bolt it in and wire it up. i would mention shortening the drive shaft but you have to do that anyways. jmo.

Thread to install a 200R4 in an A-body. You can easily find a 200R4 in mid 80s GM G-Body (Grand Prix, Buick Regal, Olds Cutlass, Monte Carlo). You can also pull the shifter, tv cable and linkage from said parts car. If you get it from a pick n pull you can get all the parts need for pretty cheap. 200R4 can be built to withstand a crap load of HP.
 
I have a gear vendor in my ol' silver Duster....I like it. It probably can be done without major modification.....but the motor/trans angle is gonna be steep. I opted to modify the floor pan/tunnel just behind the transmission crossbrace/mount.....very simple and the carpet hides the modification well. By keeping the motor/trans at the stock angle, there is no need to re-do the pinion angle on the rear.

I have appx 29.75 tall rear tire. 4:30 gear, and can cruise around 70-75mph @2200-2400rpm.....the sweet spot.
 
Say i find one of the so called 200R4. What mods does the trans need to have to withstand more HP??? Do i need to find a performance trans shop or is this something i can do myself; Is there floor pan surgery to do with the 200R4???

Thanks.............................. PETE ..............................................
 
Say i find one of the so called 200R4. What mods does the trans need to have to withstand more HP??? Do i need to find a performance trans shop or is this something i can do myself; Is there floor pan surgery to do with the 200R4???

Thanks.............................. PETE ..............................................

You can build it yourself with ordering the correct parts or you can have a trusted tranny shop do it. There is not floor cutting, just on cut on the brace under the car.
 
Ever consider a 4l60-e? Don't know what is entailed as far as surgery. But you can unbolt the bell housing and get a QuickTime sfi one to adapt it to a Mopar. It is an electronic unit, so a controller can be used which will allow you to adjust the shift pattern to your liking. Will no doubt cost more $$ than a 200 but it is a more modern trans........
 
My only problem with the GV option is the ratio. .78 is too high IMO. I wish they'd come out with a .65-.70ish version. Then it would be perfect for these old cars. Run high gears in the rear ends, but still pick up that mileage on the highway.
 
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