Filou

Hi Everybody


First to know, i'm a german.
Second to know, I'm rebuilding a 1989 Caprice.


I'm rebuilding a 1989 Caprice. I had luck and found a nearlly rust free 1989 Caprice with the 305 TBI engine. But the paint was bad and the interior had seen better days and the transmission was/is broken.


I have done some modifications/improofments to the car. 4 Wheel Disc brakes and some additional HP to the engine. New velour interior and better wood applications are estimated.
But i don't know which transmission i should choose. The engine should have ~250-300HP and ~270-310lb-ft, haven't it tested on a dyno yet. Could be more or less.
The big question is, which transmission i should build in. TH 700R4, 4L60 or TH 200R4.
Will i need a new rearaxle diff?


The additional problem is, that i can only use parts, which came to the market between 1989 and 1999, to get the registration for historical eminent vehicles.


Greets


Filou

ReekyMarko

I don't know if this is gonna be any use to you, since it's been such a long time, you probably already made up your mind ;D but here's my take

From what I've heard, the 700R4 and early 4L60 are pretty much the same thing. The 200R4 is much smaller (if that matters to you somehow), but also weaker than 700R4/4L60. The 700R4 is said to be very strong in stock condition and is much more upgradable than the 200R4. I've heard that the 700R4 can handle up to 350 hp in stock condition, mildly upgraded 400-500hp and fully built up to 700 hp. So I would go with the 700R4

But be sure to use the time to find a low mileage one, these transmissions are all over 20 years old now and many of them have seen better days

And for the rear diff, it all depends what ratios are you running now, and what kind of transmission is/was already installed. I would go about installing the transmission and testing if the gear ratios suit your needs and go from there.

Filou

Thanks, but i already found a enforced TH200R4 that should be good until 400HP.
Actual i'm searching for a way to improve the transmissionoil cooling. It goes a little bit to hot when drive a bit harder.

WyrTwister

Try a transmission fluid cooler , in front of the radiator , as used by people that use the car to tow a trailer .

I would use rubber hose rated for transmission fluid for the " plumbing " . I suggest you disconnect the transmission line coming from the transmission to the cooler in the radiator .

Attach the hose to that line and attach the other end to the new cooler . The second hose connects to the second line of the new cooler and returns transmission fluid to the cooler in the radiator .

So , this would put the new cooler in series with the cooler in the radiator . By allowing the transmission fluid to return through the cooler in the radiator , the engine coolant in the radiator will more quickly allow the transmission fluid to warm to operating temperature , in cold weather .

I hear Germany gets cold in the winter .

If you live in a climate that is hot most of the time , it might be better to plumb the new cooler , in series with the old cooler , on the line that returns transmission fluid to the transmission ?

God bless
Wyr