The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1960 - 1966 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-27-2014, 02:56 PM   #1
Trump
Registered User
 
Join Date: Dec 2009
Location: Columbus, OH
Posts: 75
Sorting out 700R4, could use some professional or semi-professional input

Just getting my truck back on the road after a swap to a GM 350 crate engine and 700R4 transmission. I could use some input about the trans and its performance. During the 1980s and early 1990's I was driving a manual and never got to experience the 700R4 so don't know what it is supposed to feel like. This is a street truck, I am not racing it. I chose the combo for drive-ability and economy so I am not that worried about WOT shift points.

First here's some info about my trans and setup:
-1986 700R4 (supposed to have come out of a van and said to have been recently rebuilt....we all know how that goes) Looked ok when I opened it.
-stock torque converter
-TCI lock-up kit (new and installed by me)
-Edelbrock carb with Edelbrock geometry corrector #8026
-Edelbrock TV cable bracket #8036
-Universal TV cable (adjustable housing)
-Rearend ratio is 4.10:1
-Tires size: 235/75R15

For awhile I tried the "just set the TV cable to be tight at WOT" method. Why this is said, I don't know, I suppose it may work with another style of cable, but didn't work with mine. I did mine with a pressure gauge according the Bowtie Overdrives website for a universal cable, supplemented by tips from other sources.

So I went to the pressure gauge method and that seems to be working way better, at least in comparison. I used this chart to check my pressures at 1000rpm once I set the TV cable:


My readings at 1000rpm were:
P 75-80psi
R 110psi
N 75-80psi
OD 75-80psi
D 75-80psi
2 125-130psi (seems low)
1 125-130psi (seems low)

When I am just running the truck at idle and pull the tv cable all the way out, The highest reading I get is 125-135psi and the needle flutters between the two rapidly. This is a concern because I have read that I should see pressures in the 190-230psi range when doing this.

I double and triple check my fluid levels. It is exactly at the top hash mark when hot, just as it should be.

It also feels a bit weird. At part throttle my 1-2 shift comes in about 1200rpm, my 2-3 shift comes in about 1200rpm as well. I can not feel any shifting from 3-4, but despite that I only get up to 2200-2400 at 65mph, which would make me think that the OD is working.

I installed a manual switch with my TCI kit to turn the OD off for when I want to tow. At 65mph, I would expect the rpms to raise when I flick the switch off, but they don't change at all. It's like the switch does nothing.

So in summary, I am wondering about the pressure when I pull the TV cable all the way out. I am wondering about the 3-4 shift, and I am wondering about the functionality of the TCI OD switch. The drive-ability doesn't seem to suffer, but like I said, I don't really know what to expect, maybe I am missing out on some super vast improvement.... if so, I'd like to find it.

So if there are any 700R4 experts out there that have some input, please let me know what you think.
Trump is offline   Reply With Quote
Old 06-27-2014, 08:12 PM   #2
Trump
Registered User
 
Join Date: Dec 2009
Location: Columbus, OH
Posts: 75
Re: Sorting out 700R4, could use some professional or semi-professional input

New development. Went back out and have been messing with it some more. It seems that my TV linkage (part that links the plunger and cable) is catching on something. I jerked on it a bit and it came past whatever it is catching on and I can now get about 177psi at idle when I put the cable all the way. So that puts me in range and I feel better about the deal. Bitter sweet I guess, seems ok, but I think I will have to drop the pan to deal with whatever the linkage is catching on. Won't know for sure till tomorrow when I get the seat back in for a test drive. Installing the vinyl floor mat simultaneously and had to take out the seat. Will report back tomorrow.......
Trump is offline   Reply With Quote
Old 06-28-2014, 12:35 AM   #3
NEWFISHER
Registered User
 
NEWFISHER's Avatar
 
Join Date: Sep 2012
Location: Oregon
Posts: 3,303
Re: Sorting out 700R4, could use some professional or semi-professional input

Once you get it to push smoothly and back together, take it out and manually pull it down into first. With a higher rpm range manually shift it into 2nd. Same goes for third and then 4th. This way you can verify positive shifting of the gears. The lock up will drop the rpm by roughly 200 i cant remember which pin but you can run a light off the lock up side of the pin connector to see if its working while driving
__________________
GOD BLESS AMERICA!
NEWFISHER is offline   Reply With Quote
Old 06-28-2014, 08:15 AM   #4
Trump
Registered User
 
Join Date: Dec 2009
Location: Columbus, OH
Posts: 75
Re: Sorting out 700R4, could use some professional or semi-professional input

Quote:
Originally Posted by NEWFISHER View Post
Once you get it to push smoothly and back together, take it out and manually pull it down into first. With a higher rpm range manually shift it into 2nd. Same goes for third and then 4th. This way you can verify positive shifting of the gears. The lock up will drop the rpm by roughly 200 i cant remember which pin but you can run a light off the lock up side of the pin connector to see if its working while driving
Great idea. Thanks.
Trump is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 06:58 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com