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89 700r valve body question for lockup

6K views 22 replies 7 participants last post by  user151 
#1 ·
700R4 Transmission

I have a 700R4 I want to use with a carbureted engine....there are many kits to aid with the lock-up, but i am looking for the simplest yet most effective way for this function. I purchased one kit that stated it worked with both 2004R and 700R4 which was not true. Any suggestions on this is greatly appreciated.....
 
#3 ·
The simplest way is a Toggle switch.
It's best to use a newer style 4-Pin Brake light switch from a car/truck that came with Cruise or OD Trans, with which ever kit you choose. Run the 12V+ through the Brake switch to Pin-A on the Trans plug, this will disengage TCC lockup when the Pedal is depressed.
4-Pin Trans plug Diagram> http://www.hughesperformance.com/pdfs/HP700-R4.pdf
Lots of Wiring diagrams> http://www.rowand.net/Shop/Tech/LockupTCCWiring.htm

Cheap & Simple Kit:
http://cgi.ebay.com/ebaymotors/_W0Q...emZ250782490188QQsspagenameZSTRKQ3aMEWAXQ3aIT
This uses a TH400 1-Pin Trans plug and a Pr. switch for 4th gear. Adding a inline Toggle switch is easy. This will allow you to turn off the Lockup around town which helps prevent Engine lugging.
 
#4 ·
I have my 77 shortwide that I put a 700r in I got the b n m 70248 lockup kit, it runs off of the electric vss (vehicle speed sensor), I was told from summit tech help that its all external wiring that u,a have to do to work properly , well the instructions on the kit say on some applications you have to go into the valve body and remove a spring from a cylinder that controls clutch lockup. Does anyone know about this, cause now the tranny is in truck and full of fresh fluid it drives and goes thru all gears but never locks up at any speed any help is greatly appreciated...
 
#6 ·
i merged all your same questions / threads on the same problem to one thread here....

a 1989 valve body from a 700r4 will not have a lock up valve assembly in it. That was in the early design valve body. GM installed aluminum plugs in the bore of the valve body and at later date the bore was not even machined out
 
#8 ·
you posted in another thread the electronic speed-O was not working.

Is the speed-O working or not?

Is the VSS installed? Is the metal reluctor ring on the out put shaft?

in the photo here... do you have these two parts installed on the transmission? Or just the VSS installed, not the metal reluctor ring?



 
#9 ·
Yes I got the speedo workin, the speedo wires were spliced with the red and black wire from the bnm lockup box I cut the wires from the lockup box so I could at least get the speedometer working I did that and the speedo worked then I hooked back the lock up box and never worked
 
#11 ·
just leave unhooked i build transmisssion for a living done many 700r4s have a very good sucess rate with them i convert them to non lock up main reason im located in west virginia it a up and down hills so the converter constantly locks and unlocks tbi full size trucks and 2.8 s10 are the worse ive un pluged many of them and had really happy customers if im doing a rebuild i use a nonlockup converter and a transgo non lock up kit in all of them mainly the converter weighs less and the tgo kit adds more fluid but un hookn it will not hurt it in hilly country if u live in the mid west were there no hills that would be diffrent it would run cooler locked and lower engine rpms if u do use a lock up have it wired up to only work in 4th gear and another note as was posted earlier the 86 or 87 was the last to use a lockup valve they sell a kit to make it mechanical but i never care how they act in a low hp or heavy vehical
 
#14 ·
From PATC's site:
If you have a 1982-83-84 car or truck never drive it with the wires on the side of the transmission unplugged. This will overheat the transmission on a long trip. On a 1985 or later it is O K to have the wires unplugged, because of a design change made in late 1984.
 
#17 ·
The way the bnm kit works off your vss once you set the speed (45 mph example) it doesn't disengage unless brakes are applied or vehicle drops below 45 mph weather I floored it or not I thought a had tv cable hook properly all shifts seemed at right time, but the when I was cruising on highwAy and floored it it only bogged down never went into a lower gear someone told me that I burned up 3 4 clutch pack, I drive it around for almost 250 miles in few weeks everything ran fine except no downshift then yesterday I drove to nearby town 30 miles away I stopped at stoplight when I went to take off 1 2 shifts were normal but when 2 3 shift happened it just slipped really bad likein neutral.. Now I'm going crazy trying to figure, out what to do
 
#23 ·
SSedan64 said:
From PATC's site:
If you have a 1982-83-84 car or truck never drive it with the wires on the side of the transmission unplugged. This will overheat the transmission on a long trip. On a 1985 or later it is O K to have the wires unplugged, because of a design change made in late 1984.
This is correct according to all knowledgable websites on the 700R4. I have a 1992 in my rod and do not have the plug wired. No problems. (Though I do plan to wire it in the future only for more efficient operation...).
 
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