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........................................................... -- Cable Suggestions --
The following is a post by Wayne Petty: >got a 1986 Chevy K-10 with a 350,
all kinds of little goodies on it. the tranny is the factory TH700-R4. My manual explains how to adjust the cable,
but it doesn't seem like its describing too good cause I can't follow it at all. so, if anyone can help me out,
I would appreciate it. the cable is the stock one that came with the truck. the trans is not vacuum modulated,
controlled by the cable attached to carb. the cable is hooked up, but due to a different carb, the resting position
is pulling on the cable, so at WOT, the cable stops the throttle from opening all the way. terrible situation here.
so, please HELP
go to your trans parts shop and get a 39" replacement throttle valve cable from fits all 1800 527 2544 it has a long center cable with an adjustable screw stop which will compensate for the difference in the tbi unit you took off and the 4 bbl that you installed .(I know what you are doing) measure the centerline of the throttle shaft to the center of the t/v stud (usually 30 mm) and make sure that the replacement carb has the same dimension . if your carb has a ball you will need to change it and install a walker # 72-1350 carb lever stud available through you local carb shop .
as I recall the throttle cable needs to be maxed out at WOT for proper adjustment if the 30 mm centerlines are not adhered to you may torch the trans as the pressure curve will be wrong
best of luck
wayne fixer of most things broken
-- Idea using no lockup kit --
The following is from Tony on RRT on 10-21-99: Actually all the parts you need for the Lockup convertor to work is already in the 700 unit. A single wire case connector from a T 400 and BOOM you are flying. I have never seen the need for a brake light switch from a late model vehicle to cancel lock up of the converter.
Also from Tony: Sumner, non computer shifted 700's have pressure switches and a wiring harness in them that can be modified for 4th gear lock only. And you can use the square OEM case connector too. The single wire case connector looks cleaner and some ppl cannot figure out the proper hole to put 12 volts into on the OEM 700 case connector.
Only need to hook up 12 volts to the case connector for the convertor lock
up. With my system you do not have separate switch for convertor control like some kits provide.
I have found the best shift to 4th and convertor lock up "feel" comes from using a 2 wire lock up (late style) solenoid. You wire 12 volts to the solenoid and run the ground wire from the solenoid to the correct pressure port on the valve body. The switch to use on the VB is a single wire terminal type, normally open grounding type.
I say this offers the best "feel" since there is a few split seconds before the pressure builds after the shift to 4th to close the switch and engage the convertor.
A single wire solenoid can be used just as easily. Just wire the 12 volts through the pressure switch to the self grounding solenoid. The switch must be a normally open type, closes with pressure.
Also no electric is needed for convertor l/up. Installing a 1/4" check ball ( same size as used in the 700) into the hole on the end of the solenoid will l/up the convertor in 2, 3 and 4th. It down shifts very harshly though since the convertor is locked. A 5/16" check ball is OK also.
I have found the brake light switch cancel feature un necessary for 90% of cars. Also you speak of the convertor un locking on down hill coasting and saving some gas as the rpm drops. What is happening inside the trans is a one way sprag is "over running" and can over heat if you have a long coast. The sprag is designed to over run, but not for a long period. At low rpm the cooler/lube flow is reduced.
-- Another Idea using no lockup kit --
The following is an e-mail conversation from Jeff Fennema on 10-22-99: Saw your 700 page. Thanks for collecting the info. You can do what the TCI kit is doing for you cheaper by cannibalizing any GM vehicle with a lockup converter. Just get the vacuum switch and the brake cutout, wire the same 'cept run the wire (12v.) from the vacuum through the brake switch before heading down to the trans. TCI's diagram even looks like the GM switch. I then replied: Jeff, Thanks for the info, except I got a question. The TCI kit gives you a pressure switch which you use in the valve body (a port that only has pressure in 4th), so the converter only locks up in 4th gear. Wiring it the way you stated wouldn't the converter lock up in all gears except 1st and maybe 2nd? and he replied: Indeed it would. Just as the factory designed the trucks. I don't necessarily see any problem, as even in third, you'd be going at a good clip when the vacuum switch allowed a lockup.
Going from 'signal generator to speedo cable
Question from Darren on RRT (11-06-99)....I have a G20 van '85 year model I bought used it has a turbo 350 trans in it and I bought a 700r4 trans to put in it but the speedo sending unit has two wire plug and my van has a cable. Can the sending unit be changed or does the tail shaft assembly have to be changed?
Tony Says... The output shaft has a "signal generator " on it for electronic speedos. It's a metal disc with thin square edged teeth on it. Pull it off and there should be a hole in the out put shaft where a regular metal retaining clip for a plastic speedo gear will install.
Tony has a lot more on this subject on his 700R4 pages ( converting to cable )
Also from Tony: Look here for a speedo cable inline signal generator for ECM's.
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