This is for our wagon project:

Which tranny would you guys use for this sled?

It's a '68 Tempest Wagon with a nice lil 350 SBC (probably about 320HP or so) going in it with a Chevy 12 bolt runnin 3.73 gears.
This car is going to be a business promotional vehicle for my wifes business so she will be driving it pretty often and sometimes up to 100 miles in a trip. The car is also going to be used as a wedding Limo and must be completely dependable. However, I guess either one would be as dependable as the other.

I'm at a point where I can get either the TH350 with a fresh rebuild and Transgo kit - 0 miles.
Or a 700R4 from a 84xxx mile 90 Iroc-Z for the same price. The 7004R4 is suppose to be in excellent shape, but I would probably have it checked out anyway and proably put a trans-go kit in it.

Not quite sure if the 700r4 can handle 320, but I think it can. If so it would be nice to have the OD for any long drives.

The th350 is also a great choice. The only real problems with the 700r4 is that is has a huge drop between first and second, but it has overdrive.

will the ratio drop from 1st to 2nd gear be that noticable behind a mild small block with the 3.73 gears if I go with the 700R4?

I would use the 700. How often is your wife going to beat on the car?

The drop is not as bad as people make it out to be.

Put a transgo kit in it.

My dad rebuilt a 700 for me and so far its been going well. Gotta love overdrive.

Why not a tweaked 200-4R ? Built right they can easily handle 320 HP (at the rear wheels), are an easier swap than the 700 and have a better gear spread. They are the same length as the TH350, use the same driveshaft and the rear mount is in the same position as a TH400. My buddy runs a tranny shop and they build quite a few for street machines and rods. They built one for a '67 Olds Vista Cruiser running an Olds 455 that dips into the high 12's. JMHO

Gear Vendor Overdrive unit on the back of the TH350? There just happens to be a group purchase forming up. See the Gear Vendor Post. You can keep what you like about the TH350 - only trade off I see is the 700R4 has more overdrive .70 where the GV unit is only .78.

I would go with a 700 or 200, make sure its in good shape and you'll love it w/ the 3.73's.

Otherwise, my current driver wagon project is getting 3.08's because I'm not using the OD.

Thanks for the replys fellows,

Well, its a done deal. I picked up the 700r4 last night and am taking it to the tranny shop this morning for a check-up.

The guy I bought if from also included the shifter and linkage from the Iroc, so maybe I can make some of it work in the Wagon.

He also gave me a "new" torque convertor that he bought for it that he never installed. But, I can shake it and hear a clunk in it. Is that normal for a dry TC?

Thanks

Dwayne

Hey,...

I went through this 100 times when I was deciding what combination to go with on my Chevelle. The bottom line on your car seems like its going to be dependability and drivability. It may need or may not need to be fast in order to be a promotional, but overall, you have to be taking into account that your wife is going to be driving the car, and you said its going to be used on long trips, and to shuttle customers. Theres nothing more important in this case then what I stated above. Everyone has there own opinions on this particular topic because theres just so many transmissions to choose from. The Th-350 is a good transmission for daily driving and local driving and an even better one for drag racing. Its very strong but not as strong as the TH-400. The 700R4 is weaker then the two but can easily be made just as strong if not stronger. The first gear is very short and very quick to give you a good launch,... but whats so great about this transmission is that It has OVERDRIVE for highway use. I believe its .70,... thats a pretty good overdrive. On a 320 horsepower car if shes not beating it every two seconds and lighting the tires she should be ok. The 200R4 is very similar to the 700R4 but some feel its a little stronger. The gear ratio is also slightly different. I cant remember exactly how. These days, I also see people installing 4L60's and 4L80's used on newer cars like the late 90's - today corvettes and camaros. They are much stronger and much more common these days. They are also a little pricier. I think overall that its important to have an Overdrive for the highway, to bring both the RPM's, Noise, and Gas used Down. I love to drive my 71 Chevelle SS 396 and unline my buddies drive it I do. I take 200 mile trips in it on a regular basis during the summer months. But I really struggle on long trips with Flowmasters, 3.73 gears, and a TH-350 doing 75MPH@3200 RPM, Good luck,

Dan