700R4 Conversion - Driveshaft Installation Q.

[Kritter]

I am in the process of converting a 73 to a 700R4 tranny. I had the driveshaft shortened and new ujoints installed. The front slip yoke is not a bolt up, and I cannot get the driveshaft past the differential in order to gain the room needed to slide the yoke into the tranny.

Is there an easier way to get the needed room to slide the yoke into the tranny other than lifting the engine with tranny attached?


Kritter

 

[mmvette80]

When I installed the 700R4 in my car I had bought the yoke from the company. First I installed the yolk then lifted the driveshaft up and bolted the U joints to the yolk and the differential. There is supposed to be about a inch of play between the yolk and the tranny. Put the differential U joints on first then lift the front of the driveshaft and bring the yolk to the u joint. I think this is the question you were asking. Hope it helps

 

[Kritter]

Thanks for the thread. I had the driveshaft shortened and the shop installed the 700R4 Slip Yoke (non-boltup front yoke). When I got it home it seem virtually impossible to get the rear end past the differential in order to gain the room needed to slip into the tranny. Well, after carefully wedging it in every direction I found one that worked. Then it was easy to drop the tranny tailshaft down to meet the yoke. I did have to remove the needle bearing caps to get it to clear the rear differential.

It is possible to install a non boltup front slip yoke without pulling the differential or raising the engine. Not fun, no room to work, but possible.

On to the next conversion....linkage.....

 

[mmvette80]

What linkage conversion are you referring to? Is this tranny from a donor car? The stock linkage worked for me.

 

[Kritter]

Unfortunately the tranny is not from a donor car so I don't have any linkage except the original from the 350 turbo. I am planning on making a trip to the salvage yard to see if I can locate one. If I can't find one, I will have to go to 700R4.com for their kit. Thanks for the pic....

 

[mmvette80]

You will not regret doing the swap. Its amazing. I find I cruise at 75mph all the time. Off the line it takes off like a date rape. I got the 2200 stall converter.

 

[Kritter]

I am really looking forward to driving it. I have had the 73 for about a year spending most of my time rewiring. The nut that owned it previously put aluminum foil in the fuse box. Burnt most inside wiring. Converted the distributor to an HEI, installed headers, made new fuel line and made tranny lines. Getting close, I think I can see light at the end of the tunnel (hopefully not a train).

 

[mmvette80]

Good Luck with the tranny. Who did you buy it from? How is your engne, whats the hp/torque? What rear?

 

[Scott81]

Kritter-

If you are doing the install yourself let me say that TV cable setup is VERY important, it must be lined up correctly and then adjusted correctly. If you need any help let me know, I also have a pressure guage with a 6' hose that will help with getting it adjusted so if you don't have one let me know and I'll send it to you. I still have the directions for setup at home, I can send you a copy as well. 700r4.com has instructions on their site too I believe. Line pressure in P-N-OD should be around 150psi and 1-2-R should be near 300.

 

[Kritter]

Scott, Thanks for the information and the offer. I will take you up on that. Just contact me at Mark.Kritser@mail.sprint.com.

 

[mmvette80]

I just took a nice cruise with the new 140mph speedo. The tranny shifted into OD @ 120mph. 105mph comes in @ 3000rpms. What a difference from the T400. :L

 

[Kritter]

Wow, great performance. I made some good progress this weekend getting all trottle, TV (not adjusted), and shift mounting brackets from a local Corvette Challenge drag race event at KCIR.

Still waiting for the PS Control Valve. Should be ready to adjust TV cable next weekend, baring no major leaks.

Thanks for all the help.

Kritter

 

[400hp_76]

torque conv. lockup

I am also installing a 700R4 in my 76....I have the new shifter so linkage is not a problem.. I know the drive shaft will have to be shortened and the crossmember altered(or just buy the crossmember that was pre-fab. by 700r4.com) My question is about the wiring. I know i have to have the Tv cable and a lockup wiring harness. i know b&m makes a good lockup kit and painless does also. which is the best.

 

[topless82vette]

MMvette

how did you make your 700r4 stay in overdrive at 120mph mine always kicks out of overdrive around 90 and will never go back into overdrive after that, my 700 is out of a 90 vette as the original 700 ground itself into small metal shavings as did most other 82 700's, so whatever you put in your 700 should be available for this 90 700r4

 

[mmvette80]

When I was looking to get the 700R4 I asked the question that I had read in the Vette magazine a hundred times. I dont want it to shift in and out of OD constantly. I had two options. I went with the 75% throte valve. This means that if im cruising and I want to pass someone I have to press the gas pedal three quarters of the way down in order to kick out of OD. The other option was wide open throtle valve. This is for Corvettes and can be ordered through Chevrolet. When you hold the gad pedal to the floor it will shift out of OD like as if it was 4 forward speeds. I have a "updated" 700R4 and all the bugs are out of it. I guess thats why I shifted into OD at 120mph. Look up www.700R4.com

 

[mmvette80]

I took it out today to make sure it would hold in OD @ 90 mph. I was in OD @ 60mph and gradually went up to 110mph. It never came out of OD. My RPM's were a little over 3000.

 

[400hp_76]

4.11s

Installed my 4.11 gears last nite. I have had the tranny ready for about a week(excluding the tv cable and T.C. lockkup harness). the 4.11s and the lower gear ratios in the 700 should make a little better use of my 400 horses. how much did it cost to get the driveshaft shortened.

 

[mmvette80]

I think I paid $40 to have the driveshaft shortened. Ask the company who is doing the driveshaft what to measure.

 

[Kritter]

It cost me $65 for shortening, $15 for the new rear u-joint, and $30 for the new front U-joint.

Just make sure you call the shop where you will be taking the shaft to and confirm their measurement needs.

I had a interesting time installing the driveshaft (ie. getting the rear past the differential in order to be able to slide the yoke into the tranny). Finally pulled the caps off the new rear u-joint (gives just enough clearance to get past differential), removed the distributor (too close to the firewall), and tilted the rear of the tranny about 4-5 inches.

 

[400hp_76]

i am taking my vette to a shop near me and having them shorten the driveshaft. they warranty any defects and replace the driveshaft if it breaks. They only do this if they measure the driveshaft .. they dont warranty if you do the measurements. sound like a good deal to me.