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zfuel 03-24-2012 03:30 PM

700R4 Shift problem?
Ive read tons of 700R articles and none seem to quite fit my scenario. I have a 85 Gmc Sierra classic swb 2wd. It has a factory 700R4. It had a 305 in it, and the last week I've spent swapping in a 350. Trans worked fine (by my standards) before engine swap. Shifts seemed a little slow and soft after it got heated up, but didn't seem like a big deal to me. Today, finished installing my new motor, broke it in, and started trying to tune the tv cable. Fluid level is good, and I spent 4 hours trying to work out the tv cable so that it would shift right. Never has. Always slams into gears, super-late, no matter where the cable is. I have a Holley 4160 carburetor, but I have the throttle bracket & nessecary geometry corrector for tv cable. I'm at a loss. The only thing I can come up with is something inside the transmission, and that I'm going to need a rebuild. I read the bowtie-overdrives article and that has lead me to believe that it has what they call the short spring syndrome. Advice?

Prof. T. Soggmeyer 03-24-2012 05:20 PM

tranny trouble...
Are you sure the geometry is correct on the tv cable? at idle the cable should be ALL the way in with no slack, and at w.o.t. it should be ALL the way out.

zfuel 03-24-2012 05:23 PM

I set it according to instructions, it is fully out at WOT. It does however, have around 1/4" slack beyond the teardrop at idle. Not sure how I would go about fixing this?

Prof. T. Soggmeyer 03-24-2012 05:34 PM

You need to change the geometry of where it attaches to to carb. I simply made an arm and positioned it so it traveled the correct distance. The farther from the pivot you go with the cable hook-up,the more it will pull the cable. I will post a pic of mine if you'd like.

zfuel 03-24-2012 06:21 PM

Please do. I'm not exactly sure how id do it

Prof. T. Soggmeyer 03-24-2012 08:03 PM

pic of tv hookup
1 Attachment(s)
Hi zfuel, in my picture you can see the red arm that I made from flat bar to extend the geometry on the tv cable. :thumbup:It'a crappy picture but it's cloudy here so not much light. I have an edelbrock carb.

SSedan64 03-24-2012 08:03 PM

The TV Plunger should be even with the Valvebody when the TV Cable is fully pulled.
You shouldn't have 'any' TV cable slack at Idle.
What TV cable Bracket and Geometry corrector are you using?

Disconnect the TV cable, Engine idling, pull the TV cable out a dozen or so times & let it snap back. May clear any trash, sticking/binding TV or TV plunger.
Now try to readjust the TV cable.
Scroll down to where the 'Red' writing starts. Paragraphs 1-9, there're 3 Pics between 5-6:

zfuel 03-25-2012 05:55 AM

That is the bracket I'm using. And geometry corrector p/n 20-121. I think maybe my throttle attachment may be a slight bit too high? I had to engineer a spot for it, I'm headed out to fix it now and see if it works then

zfuel 03-25-2012 06:32 AM

Alright, moving throttle didnt fix it. Here is what I an dealing with.

SSedan64 03-28-2012 09:15 AM

Looking at Holley's instructions, the Throttle cable should be connected higher up on the Carbs' Linkage, not on the TV corrector.

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