th350 to 200-4r swap

[chevy4life]

Hey guys, I'm planning out a 200-4r swap to replace the th350 in my 72 chevelle for this winter. I'm pretty set on what i need except I have a question about cooling. Do i need a separate transmission cooler? or can i put new fittings on and use the cooler for the th350? the car will be street driven, no race. thanks, anthony

[spacepirate]

Why go with a 200r? Why not a 4l60 or 80?

[1966longroof]

200-4r has a good OD of less than .70. For a daily driver a good all around choice. Some companies are building them to handle over 600hp. To answer your question..... yes you should be fine. Just make sure that since you are going thru the endeavor to use new fittings for a clean/leak free seal. Which lock-up controller you going with??

[chevy4life]

Thanks guys for the help! I am keeping my 350sbc and want to avoid all of the wiring that comes with a 4l60 or 80. Also, the 200 avoids having to shorten the drive shaft which saves a whole lot of headache. I like the B&M controller, it seems to have good reviews. If i have to get a new converter, is a lock-up really that beneficial?

[MarkB]

The 200-4R is a good choice for this type of application. As you know the drive shaft will remain the same. If you can track down a factory 400 crossmember it will work great as well. I recommend installing an external transmission cooler. I would also highly recommend a plate design cooler, this is the most efficient design. If you go with a 25,000 - 30,000 GVW rating cooler you will be good. As far as the lock-up converter. I would highly recommend using a lock-up style. There is no benefit to run a non-lockup. With the quality converter options and the options to control the lockup it is the best way to go, plus you will run about 300 RPM lower and will help reduce heat. You may check out our lock-up module as well. We operate just as OE originally intended, electronic lock-up, no vacuum, only locks up in 4th gear and will unlock when it down shifts or if you tap the brake. Don't forget about the cable system as well. This is the life of the transmission, the cable controls the line pressure, so you don't want to mess around. We know that there are other options, but our Tru-shift is the only self adjusting OE style system on the market. We would appreciate if you would review our products for your application.

Good luck with the project. Should be a good combination.

[Thephranc]

I ran a small cooler (7 x 10) on the TH350 and the 2004r and it cooled the 2004r just fine. Just remember the top line is out.

[jakespeeds]

I did it in my 73 Nova SS years ago. I still have the cross-member if you're interested. I had the OD hooked up to my lighter and used it as the ground. Push in the lighter and OD kicked in. No one ever knew.

Jake

[obengston]

I converted over from the T350 to a 2004r as well (had it built by Extreme Automatics). It came with a 2yr warranty to handle 1000hp with a trans brake. I ran mine through a external cooler, and have had no problems. I have a trans temp gauge. I use a non lock up converter 3500 stall. I also put a sensor on the pressure port thats connected to my Dakota Dash, so I monitor my pressure at all times. Like was mentioned already the biggest killer to these transmission is the line pressure. I figured if I can monitor my temp, and pressure I should be able to see any problems. Can't beat that 2 year warrant..lol Love the OD, plus the ability of this transmission to handle the power.

[camaro427-69]

just make sure if you get a built one that you get a good input drum. i had a non-lockup 700HP built one but broke the cryo whatever hardened input shaft on the first burnout i did when it shifted into 3rd gear. replaced it later with a CK-transmission direct input drum and never a problem again but that piece was another 500$ if i remember right but those hardened stock pieces are just crap. but if you want to overdrive why not going manual on a street car? i did later and i´ll never swap back to automatic again. just a thought.

[BayouSS]

I would listen to Mark's advice, he's always willing to help even if its not his product.

[chevy4life]

This is all great information guys. It really has given me so clearer views of doing a swap. I have stayed clear of the manuals because im using the car for manly cruising around and i dont want to have to deal with shifting. just want it to be the easiest drive possible. I have heard some bad things about having the manual lock-up. is that true about destroying everything if you were to forget about it? I wanted to make this swap as simple and affordable as possible. I cannot stand the 350 on the highway revving so dang high!

[camaro427-69]

btw. i had a non lockup version and was glad not to deal with the electronics but now it is no big deal. the only thing i got rid really fast was from that 3500 stall converter cause it just sucked for just street driving if you have to drive a lot uphill. i live in the austrian alps so you could probably imagine. if you live flat and race a lot ok. got an 2000stall later and never had any temp or else problems again and i hauled a lot at constant speeds of 100mph+ on austrian/german autobahn with just a regular sized cooler. just make sure about the line pressure like some guys mentioned. you gonna love the difference of that overdrive gear.

[chevy4life]

wow, i can't even begin to imagine how amazing it must be to be able to drive a car like yours in those kinds of places. must be breathtaking!! I will not race this at all, strictly street so i will go with a lower stall speed. Do you think if im staying with a 350sb without going over the 400hp mark i need a fully built performance transmission? I wanted to do this on as much of a budget as i could without sacrificing reliability.

[camaro427-69]

wow, i can't even begin to imagine how amazing it must be to be able to drive a car like yours in those kinds of places. must be breathtaking!! I will not race this at all, strictly street so i will go with a lower stall speed. Do you think if im staying with a 350sb without going over the 400hp mark i need a fully built performance transmission? I wanted to do this on as much of a budget as i could without sacrificing reliability.

i think this question is best answered by mark

[cutlassmann]

Been reading this and I got a question I have a 1972 cutlass with a built 350 olds 520/523 lift cam Today I was riding in my car and when I get it up to 60 mph I would press the gas and it feels like it won't switch gears it's a 350 turbo when I'm riding around 60-65 I'm at 3000 rpm I have a 3.42 gear 22-2600 stall any idea on what's going on are what I need to do help!!! I been thinking about going with a 200r are a 4l60E what should I do should I change my gear etc thanks