What tranny should i use???

[vikingfan]

My turbo 350 just went in my 69 shortbed stepside and i'm wondering if anybody has input on what tranny i should go with next. I would like an overdrive and i have about 400 hp in my engine. Also, with any other kind of tranny, like a 700r4, would i need to do any modifications? Lastly, any input on stall?? Thanks everyone!

[71chevylowrider]

Alot of guys go right to the 700R4, make sure you get a good one, not just a used one from a junkyard, they need to be built up a little to handle the abuse, I know a guy fairly local (longview) that builds them if you want to talk to him let me know.

[SactoJim]

If you want the benefit of better acceleration (due to tranny gearing) and better gas mileage, go with either a 200R4 or 700R4. Either one should be strengthened to deal with your 400hp. The 200 is the same length as the 350 with a 6" tailshaft, but the 700 is longer and will require the shortening of your drive shaft. Both will require the relocation of your crossmember which is easy and only requires drilling some new holes. They will both require some minor electrical to operate the lockup torque converter.

As far as stall....usually you should pick a converter that's rated stall RPM is just below your typical cruising RPM.

There is tons of info all over the web regarding these trannys and on this site as well.

[Orange]

Man, I can't say enough about my new tranny.
It is a Godfather 700R4 from Maddog Transmissions.
www.maddogtransmissions.com

I absoultely love it.

DLB

[GREASEMONKEY72]

are the 200r4's and 700r4's geared the same? but the 200 just bolts right in? which ones better?

[Orange]

Originally Posted by GREASEMONKEY72

are the 200r4's and 700r4's geared the same? but the 200 just bolts right in? which ones better?

http://www.oldengine.org/unfaq/leadfoot/trans.htm
That's the ratio comparison between any tranny you might even consider.

The 700R4 isn't a bad install. In fact - the "worst" part is the TV cable, and that is really simple with the TV Made EZ from Bowtie Overdrives. And, you have to do that with the 200 or the 700, so, take your pick. The 700R is a lot more common, and it can handle more power.

From the BTO website:
"Installing a TH-2004R transmission into a vehicle that already has a TH-350 or Aluminum Powerglide is normally very simple because the Th-2004R is only slightly over 3" longer than either the short tail housing Th-350 or the long tail housing aluminum PowerGlide and is the same length as a long tail housing Th-350."

"Installing a TH-700R4 transmission into a vehicle that already has a TH-350 or Aluminum Powerglide is normally very simple because the Th-7004R is only slightly over 3" longer than either the short tail housing Th-350 or the long tail housing aluminum PowerGlide and is the same length as a long tail housing Th-350."

Doesn't make any difference there.

DLB

[GREASEMONKEY72]

thanks Orange - so the 700 and the 200 just bolt in with no DS mods? just the crossmember?

[SactoJim]

1st gear in the 700 is deeper than the 200 (something like 3.06 to 2.76).

The 700 will allow you to accelerate a little quicker than the 200, but the RPM drop between 1st & 2nd in a 700 is more substantial than the 200. If your truck makes good torque it will be fine. Alot of people prefer the 200 because of the closer 1st to 2nd gear ratios.