AndyG123

Hello, I was wondering if anyone could give me info on a good trans for my setup. I currently have a 450 HP and 600ft lb engine, it's in an 86 custom cruiser, with a the 2004-r, and It slips really bad going into second gear. Is there anything I could have put in to eliminate this? Or is it cheaper and easier to go to a bigger trans like a th350 or th400 or even a 700r4. If you guys have any input or experience it would be great. Thanks

69455

Since your electronic think about a 4L80E

AndyG123

what do you mean by this? The tranny has a TV kickdown, the only thing that's electronic is the lockup on the torque converter

Olds64

You will find that many on our site suggest sticking with the 200 4R. The 700R4 has bolt pattern issues, you would need an adapter. For the 200 4R to live behind a 455 it definitely needs to be upgraded.

AndyG123

any ideas on how I should upgrade?

csouth

With the weight of that vehicle and the torque of your motor, you definitely need a proper transmission. Neither the 700r4 nor 2004r were made to stand that kind of power in stock form. If you're looking for a cheap high horsepower solution for either one of these transmissions, I don't know if there is one. If you really want to keep the 2004r, I would definitely snoop on the Turbo Buick forum for feedback.

AndyG123

well Im open for options. Would a stock turbo 400 be okay? I know I would have to change the yoke, or what about a turbo 350?

Vistabrat72

The main problem with the 200-4R is the way too little 2nd gear band in conjunction with too low line pressure. Add to that the 2nd gear servo that has a very small apply area, meaning very little hydraulic surface area to give clamping and 'holding' strength, this leads to a short life behind an engine with large amounts of torque. You can read up on Grand National servos, etc, much is written about this. I went one further on mine with hardened parts upgrade, and a wider then stock red Alto band as they are called. I also went with a Sonnex (spelling?) servo that has a much larger apply area on the piston for the hydraulics to work with. Also done was a valve body reprogramming kit from Trans-Go to clean up the shifts, they get progressively harder the more I step on the accelerator. The kit includes a larger diameter pressure regulator valve to do wonders to hydraulic pressures. Included is a movie from my You Tube channel about another little trick involving the 1-2 accumulator. The channel has quite a few movie clips about overhaul and modifying the Turbo 200-4R. Links to follow below.

Vistabrat72

Two movie clips, there are many more dealing with 200-4R's. It was a learning curve, but if it helps others, it has been worth it!

AndyG123

thanks so much man! This is exactly what I was looking for as far as advice. Thanks man

Vistabrat72

You are so welcome Andy! I really hope they help! You will have literally hours of clips to watch.

AndyG123

cant wait! Also, you have a pretty sweet wagon!
​​​​​​

Vistabrat72

Thank you!

Fun71

I thought the TH200-4Rs had weak input shafts, with some versions being much weaker than others. This would be a big concern with a 600 ft-lb BBO in front of it.

steverw

CK Performance sells makes and sells the billit pieces for 200R4 transmissions, as well as turn key trans at several performance levels. I talked to him alot several years ago, but i went with my turbo 400 and a Gear Vendors over drive. Theres a guy in Texas who builds the 200r4 and claimes he has them behind his 700ish hp Buick 455 GSX

Vistabrat72

As mentioned by steverw, there are many hardened and upgraded parts for the 200-4R. Mine has the hardened stator support shaft and the later model hardened sun gear shell. It also has the later model low sprag torrington bearing versus the plastic one I had in place at first not knowing it did not like hard shifts. It let me know in a spectacular manner! One of my movie clips shows thin. A learning curve! My stock input shaft has done alright behind the mild 1972 350, but if I do ever go to a 455 or 425, the input shaft will be upgraded. The 200-4R is a very good unit in power flow and design, and with these few, albeit a little expensive upgrades, they live good lives.

Vistabrat72

Andy, Turbo 400's are a very robust transmission, needing little in upgrades to make them work well behind strong engines. I have always loved the units for their decent shifts in many applications I have driven, and their 'step' design of up and down shifting makes them great for stop and go driving with little wear and overlap/tying up of clutch elements. They are very simple units and have a lot of clutch capacity and surface area in even stock form. Turbo 350's are a lighter unit, and I have seen them work decently behind big blocks as well with a few more upgrades, notably in 2nd gear sprags, etc. They don't eat up as much power (the 200-4R eats even less!) as the THM400. But the caveat with the THM350 and THM400 is final drive gear selection. We have been so spoiled by overdrive transmissions, that driving a vehicle with even 3.42's on it with a 3-speed has us holding breath awaiting that 4th gear overdrive shift! 3.73's and up make a long distance ride almost annoying to the ears, especially with a big block. It most cases at 60 MPH you are doing roughly 3000 RPM with a THM 350/400. Now add on a 200-4R with it's .67 overdrive, we take 3.73 X .67 and we have a 2.49 overall final drive! Delightful on the open road! I enjoy this on our '72 Vista Cruiser very much.