I'm not sure which way to go. I want to put overdrive in my stock 72 Cutlass S with original 350 motor/TH350
I bought a new 3.73 ring and pinion and a limited slip differential from Yukon. I bought the car about a year and a half ago, and was told that the miles showing on the car are actual.
Right now I'm showing 53,431 miles. I'm not looking at making it a drag car, I just want a nice cruiser with some get up and go. Eventually I'd like to get it to around 300HP. I'm getting ready to have the top end rebuilt and add cam and intake. Originally I was thinking of swapping trans for the 200-4R, but just recently I was wondering what would work better. Adding
the Gearvendor overdrive, or going with the 200-4R. Any thoughts are appreciated

 

A 200R4 with the right cheap upgrades will be good for a mild 350. For more powerful engines, go 4L80.

I have a gear vendor in my car, if I had to do it over today I’d go 4L80 without a doubt. The cost of 4l89 stuff is much cheaper than when I bought the gear vender, The lockup converter would be nice, not to mention being able to program shift points.

 

The 2004R is such an easy swap, just move the crossmember back and swap emergency brake cables. The .68 OD ratio and lock up converter will work great with a 3.73 gear. A basically rebuild with minor hard part upgrades and boosting line pressure should be enough to live long term.

 

I have a 2004R behind a 455, and I have absolutely zero regrets! Granted, I had the 2004R beefed up following a guide by Art Carr Transmissions. I drove my Cutlass over 2000 miles on a Christmas road trip and it got 17 mpg running a pretty consistent 85-90 mph. I have a .60 over 455 with Sniper EFI and a 3:42 rear gear for the particulars. Ultimately I had around $2500 in the 2004R by the time it was done and installed.

 

Appreciate all the advice. I'm not going to be doing the work myself. I don't have the tools, facility or the knowledge to get the work done with the best results.
If I do go the way of the Gearvendor OD, I will make sure my TH350 is in good shape. Looking at cost wise, I thought it might be cheaper to go with Gearvendor.

 

Wow. I have'nt checked locally but I did'nt think I could find a good 200-4R for $2500
The Gearvendor goes for $2795 for my application

 

Trust me, they aren't easy to find. But, the total bill was $2500, tranny, build, and labor for install. First time i ever did something like that so I don't have any idea on pricing over all. I had it done about a year ago.

 

If you have zero plans for more power, swap in a 200R4. Get the CK performance valve body, servo, and govonor package, and have those parts installed in either a good used trans or a rebuilt one. I would think you could easily do the swap much cheaper than a gear vendor.

A 200R4 in good condition with some cheap valve body upgrades will easily handle a mild 350.

If a 455 swap, or serious engine upgrades are planned, then a 4L80 is the way to go. While you can upgrade a 200R4 to handle serious power, it get expensive really fast.

 

I have ruled out the Gearvendor OD and will be going with a 200-4R. Like I mentioned before I will not be doing the swap myself. Not something I want to do
with the car on jackstands. Trying to find a good local shop to do the swap as well as my top end rebuild.

 

What trans is in the car currently? Unless it's a TH400 you will need to change the front and intermediate e-brake cables. If it is a TH400 you will need a new driveshaft.

 

If you've got an update, fill us in!

 

There are dozens of rear gear RPM calculators out on the web. Study those before deciding on the rear gear.

I installed a TKX in my 70 vert. It is a direct bolt in. You just need to be specific about the type of shifter and lever you currently have. In my case the console mattered a lot. Plus my Muncie had a comp plus shifter already, that had a different offset configuration for my console.

My car has 3.42's and a mediumish cam. I have to be 55 plus mph to use OD otherwise the motor is a bit unhappy. Cruises great and shifts like butter. like an old school T-5,.