El Camino Central Forum banner

700R Swap

3K views 13 replies 9 participants last post by  awest 
#1 ·
I'm thinking about putting a 700R in my Elk. The tranny doesn't come with a dipstick. What do I need to do about that? Also, I've seen some stuff about using a cooler. Anyone know anything? And then shortening the driveshaft and moving the crossmember. I could really use some help in all of this. Thanks.
 
#3 ·
Why exactly do you want a 700-r4? If you're just looking to get it for the fact that it has overdrive, you could always go with a 200-4r. It's not as strong or famous as the 700, but it is a 4-speed auto overdrive tranny and I've seen some performance ones that do handle quite a bit of power. Mine handles 450. And it's just about the same size as a TH350, so if your car is equipped with one which I'm assuming you do, the whole project will be a lot cheaper, as you wont have to modify your drive shaft to fit it. It's an easier alternative , but it may not be what you want but I thought I'd throw it out there for consideration. Also, you can get a transmission fluid cooler pretty much anywhere, it's an easy project so don't worry too much about it. Just a matter of hooking up and routing some lines to where ever you mount the cooler.
 
#4 ·
Put a 700R4 and lock-up converter in my 83.
Yes, you have to shorten the drive shaft and re-work the cross-member.
While you have the shaft out, would be a good idea to put new u-joints in as well.
Trans. cooler sure will NOT hurt anything.
Worth while investment while you are at it.
 
#6 ·
I swapped out my 3 speed and went with the 200 4R on my '85. Found a local shop to do the work. Very pleased with the four speed.

Robby
 
#7 ·
Yeah, go with the 200-4R. Should mostly plug right in the drive train. You will need a switch for the clutch/lockup converter and hook up a TV cable to the carburetor.
Lots of good information here.

http://bowtieoverdrives.com/index.shtml

Doug
 
#8 ·
the whole package not inculding tranny would be like 400 bucks for everything you need..that seems like a really good deal for somthing thats stouter than the 200r either way you would have to do mods for monting drive lines and what not so why not go with a better tranny? stay the 700r4 route :p
 
#11 ·
while the th2004r is the same overall demension as the th350 the mounting pad is about 6 1/2 inches rearward so the crossmember has to be modified and anything using it as an attachment point--(emergency brake cable, exhaust hanger etc) also needs to be reworked---the th700r4 is about 3 1/2 inches longer overall, the mounting point is within 3/4 of an inch of the th350 so just elongating the hole will get it mounted then its a matter of shortening the driveshaft 3.5 inches and all is good...both require a little fabrication to get them in and both are more than adequate for the job---the th700r4 has a wider gear ratio and so it might be a little better for towing (3.06 1st, 1.62 2nd, 1.00 3rd and .70 4th) but the th2004r has a closer ratio and "might" be better for cruising and racing (2.68 1st, 1.58 2nd, 1.00 3rd, and.68 4th).................Dan
 
#13 ·
Hm. I suppose what you say is true oldcoot,I had forgotten about that because all I really had to do was slide the crossmember back a few inches to different bolt holes on the frame and use this little attachment to get it to bolt up to stock mount points:


Like 69tremec said though, it all comes down to preference.
 
#14 ·
• 700R4 and 4L60 use the same yoke as the TH350 (smaller than the TH400).

•Driveshaft needs to be shortened (measure from the back of the tailshaft, or flat transmission rear seal surface, to the flat of your pinion flange at, or as close to ride height as possible).

•Transmission cooler lines fit with minor realignment.

• Speedometer cable requires no modification. Hooks right up.

•Transmission case is slightly larger on 4L60 (no clearance problems on this El Camino, could be tight in other applications).


•Transmission crossmember needs to be moved forward from TH400location (rearward from TH350 or Powerglide).

•If using a single-pattern flexplate, be sure it matches the bolt pattern on your converter before installing the transmission. Dual-pattern flexplates should not be a problem, though you may consider using one that's SFI approved.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top