Hello,

I am contemplating converting my 1966 442 4 speed car to a 2ooR4 automatic. My question is about the existing 4 speed shifter hole: will anything have to be cut out of the floor to accommodate a shifter for the automatic. The car does not have a console so that will not be an issue. Thanks in advance for all your help. Larry

PS: Yes, I am keeping all the original stuff in case I want to change back.

 

I would think all you need to.do if fab up a plate.to cover the hole that the shifter fit thru, and bolt your new shifter to the plate. Im not real familiar with the floor of a 66. Im guessing the answer.to your question depends on what kind of shifter you want.to use.

 

I got rid of my 300 junkaway tranny, and replaced it with a built up 200 4r. I'm not sure what the hole differences may be, but it may depend on the type of shifter you put in. I can't think that there would be a whole lot of cutting. I had 4:56 gears, when I switched trannies. 70 mph was top, but fun. I screwed up and put the original 2:73 rear end back in. Speedometer is correct, but watch the rear end ratio. On paper, the car should do over 150 mph. I can get 23 mph on a flat surface at 80, but any change in flatness keeps the tranny shifting up and down. Check the RR ratio, before making the switch. I'd like to have 3:23's or even 3:45's. I have a BM wratchet 4 speed shifter. I guess I could measure the hole in the floor, from the heater outlet, if that would help you.

 

I would not go below 3.42 gears if you are swapping gears. I run at 1850 rpm at 60 mph with short 25.6" tires and 3.42 gears. Is it the ease of shifting you are looking for with the 2004R? For a similar amount for a built up 2004R, get the new McCloud 5 SPD that doesn't require cutting up your floor and gain OD that way.

 

There were hundreds of thousands of cars built with the 200-4R and rear ends in the 2.41-2.73 range. These cars all had V6 motors or anemic 260/301/305/307 motors. The run fine on the freeway. Yeah, the trans downshifts out of OD when you try to accelerate - that's what it's SUPPOSED to do.

I agree that I'd personally go with a steeper rear gear with the OD trans - 3.42 would be the minimium; I'd go higher (numerically) myself. Why bother with the OD if you can't take advantage of it?

 

I have the 700R4 in mine and run a 4.10 rear gear. Around 2200rmp at 70 mph. Very acceptable to me.
Tim

 

I agree GM did put OD with stupid tall gears. I did say IF he is swapping gears and my car came with awesome 2.56 gears and OD from the factory. Those gears are fine for a daily driver or if you live where there is an 80 mph speed limit. I have ran both and the 3.42 gears are better in every way but mileage.

 

I have a highly modified 200-R4 in the 64 F-85 build, had a column shift. Has a B@M Bandit pro shifter. See pics

 

Thanks. You have given me a lot of ideas. I am thinking of the auto because of ease of driving. I will turn 70 this year and my joints nor reflexes are what they used to be. LOL. One related question: What do I do for a cross member? Does anyone make a bolt in for this swap?kl Thanks again for all your help. It is much appreciated. Larry

 

Yeah, GM did.

Just use your original crossmember. There is no need for a different one. Slide it back to the new position (which will be the same as the TH400 crossmember position on the 1967 cars) and drill new holes in the lower frame flange as required.

 

Joe, Thanks for the crossmember info. Just to be clear, I can use my 1966 442 4 speed crossmember to accommodate a 200R4 by relocating it further back and drilling new holes in the frame to mount it. Is this correct or am I missing something? Please bear with me. I am a bit slow when it comes to this stuff. LOL. Thanks, Larry

 

I'm pretty sure that's what I said in my last post.

To clarify, the 1980s cars that came from the factory with the 200-4R DID use different crossmembers. That's because of how the frame was designed on those cars, NOT because of the trans. The crossmember on those newer cars runs at an angle and you can't just slide it back.

On any 1964-1977 A-body, the original crossmember works fine. And yes, there are vendors who supposedly sell a "200-4R" crossmember for the A-body cars. I have no idea why, other than to profit from the lack of knowledge of buyers.

 

You say the car does not have a console now, but if plans are to install the correct 66 auto console with the shifter that is when the shifter cable hole is critical and will have to be to the right and aft of your hole. If you use an aftermarket shifter without console you should be able to center it in the existing 4-speed shifter hole.

 

Thanks for the clarification and shifter tips. No console is planned.

 

I have a couple thoughts. Are you going with a custom floor shifter automatic or going to a column shift? There were no non-console floor shift automatics that year, to the best of my knowledge. Not that that's a condemnation of your plan, but only a comment it will be custom.

You will need a wider brake pedal, and to remove the clutch pedal. If I were to do such a thing, I'd just remove the pedal arm and leave the mount, just in case.

For rear ends, I am of the opinion that one should be able to moderately accelerate from interstate cruise without it downshifting, and be able to downshift at WOT via the kickdown. I have, in my other car, a non-torquey Chevy 350 with 2.73 rear end and a th-350, and it sits at 2500 at 70mph, but it will not downshift to 2nd ever upon acceleration unless the kickdown WOT function is used. The reason I mention a Chevrolet here is that, if it can handle 2500 rpm and return decent acceleration without downshifting, than an E block Olds 400 should absolutely be able to accelerate well down to 2000 rpm without downshifting.

With the 200r4 0.67 OD ratio, and, assuming with your desire at this point in life to cruise comfortably, normal sized tires of say 225x70x14, which is a 27.4 inch OD, if I wanted a 2000 rpm 70 mph cruise, I'd do what Joe says and run a 3.42 or higher.

I ran the numbers with that overdrive and that tire OD, and I get a 71.4 mph cruise at 2000 rpm in that overdrive with a 3.42 rear end.

I have two last questions. First, have you considered a TH400? It's bolt in, and the car would drive the same as it does now. The only advantage an OD transmission has for our old cars is low end acceleration with the extra gear, and maybe a bit more fuel economy on the top end. No rear end swap, no speedo error.

Also, have you considered simply buying a 66 442 automatic? You would actually make money via selling the stick car for a higher price, and you would not have to monkey with the swap, nor bother the car. More so if you went for a Cutlass over a 442. I don't know your thoughts, so I may be in error on your priorities.

 

Larry, I know you've had the 1966 for a long time so selling it may be out of the question. But If you were to consider that I know of a 1967 442 factory automatic car


John

 

Hey John,

I'm going to finish this thing if its the last thing I do. LOL. I think I may have seen that 67 you mentioned somewhere before Larry

 

I’m in the process of converting my 66 442 from an automatic to a four speed . As I read through this old thread, it appears that I can use the original crossmember, repositioning it to fit the four speed , and re- drill new holes in the frame (it’s not a boxed frame).
There are currently 8 holes drilled in the frame, one forward of the existing crossmember and 4 holes aft. I would assume since it appears the 4 speed is shorter, I would have to move the crossmember forward toward the front to make it work. I know that this will also affect the e-brake cable and driveshaft length, things that are easily remedied.
Am I on the right track here?

Tom

 

Assuming your automatic is the original two speed Jetaway, a Muncie is exactly the same length. The crossmember does not need to move and the e-brake cables do not need to change. I'm sure you are aware of the pilot bearing problem with an AT crank.

 

Joe, thanks for the crossmember info. That’s great!
I was aware of the A/T crank bushing issue. Had the machine shop bore it to specs and install a brass pilot bushing for the M20 4 speed.
Appreciate the help!
Tom

 

My next thought/question……the driveline. Would that be the same as well or a new one, shortened/lengthened?

Tom

 

From above:

That means that the driveshaft is also the same length. Of course, MT cars used a solid driveshaft vs the rubber damped concentric ones used on AT cars. The AT shaft will fit and work, but you may eventually want to get a solid one made.