1966Oldsmobile

Hi guys! The ´66 F85 is my first classic car and I´m not sure if the set up is correct. I drive a ´66 F85 330 cui (320 HP) 2 speed (jetaway) automatic. Those cars are very rare where I live and now I´ve seen a TH200 4R on ebay Germany (happen once a year) Is it worth it?
I don´t want to race or go on the track, just good accelaration and good highway quality. I´ve started a frame of restauration a few weeks ago and this will be my set up: 330 cui (320HP) - TH200 4R - 3,55 rear end.
Please, what do you think/know about the Transmission and the whole set up, the choise to buy this transmission and is a 3,55 rear end good or a 3,90 better..... Is the motor strong enough for that transmission and rear end.

Thank you very much....Daniel

442scotty

Welcome aboard! You should be quite happy with the 2004R transmission and the 355 gears. You should get decent gas mileage in overdrive. I wouldn't go for the 390 gears personally. Not for what you intend to do with the car.

joe_padavano

The 200-4R has a 2.74:1 first gear, the Jetaway has a 1.7:1 first gear. Off the line acceleration will be noticeably improved. Similarly, the 200-4R has a 0.68 OD, as compared to the 1:1 top gear in the Jetaway. Your 3:55 drops to an effective 2.41 final drive in OD. I'll also point out that if you choose to go with the 3.90 gears, the OD drops that to an effective 2.65. Personally, I'd go with the 3.90s and that trans, but that's just me (actually, for a non-daily driver, I'd go with 4.33 gears and an effective 2.94 in OD). Gas is still nowhere near as expensive here in the US as it is in Europe, however.

The 200-4R swap has been well covered in this fourm - use the search function for more info. Briefly, get a trans that's been beefed up. In stock form they are marginal behind a 307. Your trans crossmember will need to move back. If you have a hardtop with the open channel frame that just means drilling new bolt holes in the lower frame rail flange. If you have a convertible or boxed frame, you'll need to weld extensions to the tabs that mount the crossmember. Your old driveshaft can be used, but you'll need the front and intermediate emergency brake cables from a 1967 442 with the TH400 trans. These are readily available from RockAuto. If you have a factory floor shift, Shiftworks sells a kit to convert your shifter for the four speed trans. If you have a column shift you're out of luck. Be sure to use an aftermarket trans cooler. Converter lockup methodology can vary from a simple toggle switch to sophisticated electronic units from the aftermarket. Good luck.