which 700r4?

[TexasRed]

event, did you get the custom spring for the valve body for that bowtieoverdrive kit?

[eventhorizon66]

Yes, the BTO kit came with a spring and I used it when I tried that kit.  After I removed the TV made ez kit, I went to the Sonnax spring because the original stock spring had relaxed was too soft, and the BTO spring was too stiff.

[Grim 82]

Well I installed the BTO kit (TV spring, under-the-carb mounted TV bracket, throttle cable bracket, and the geometry bracket on the side of the carb). With the throttle and TV cables on the same bracket there was quite a bit of deflection, so I modified the chrome Mr. Gasket throttle bracket that mounts on 1 carb bolt that I was using before the swap. By having the throttle cable and the TV cable isolated from each other and on seperate brackets there is no longer any deflection. I have full WOT travel without the TV cable hooked up. As soon as I hook up the TV cable no matter how I adjust it or the cam on the geometry bracket I can not pull WOT. It seems as if I am fighting that spring in the valve body. So far this setup is not working.
I have taken a couple short test drives, and so far it seems like it holds 1st too long, and when I do a medium to aggressive acceleration it doesn't downshift. It bogs like a manual in too high of a gear. If you punch it from a stop or do a light power brake it kills the motor.

[eventhorizon66]

Did you hook up a pressure gauge, as they recommend, and confirm proper line pressures?  Did you have a helper push the throttle (with TV cable hooked up) while you watched the TV plunger assembly for proper movement (under truck, pan off)?

Yes that spring they provide is very stiff (and also longer than the stock or sonnax spring), but the only way it could prevent WOT is if there is too much deflection of the throttle bracket or the TV cable is not self-adjusting properly (clicking to the "MAX TV" position) or both.  In any case you shouldn't drive the truck until this is corrected.

Try out BTO's tech support.  But it sounds very similar to the issues I was having and was not able to correct until I removed the system.

Be careful and take your time here, you can fry your 700 real fast if the TV cable is way off.

[Grim 82]

 :-\I didn't use a pressure gauge, and I didn't check for travel at the valve with the pan off.

I just spoke with BTO's tech support and explained what I have going on. He told me that I need to shorten up my accelerator cable to compensate for the added resistance of the TV system. Like I said, I have full WOT travel without the TV hooked up, but I don't with it hooked up. By using 2 seperate brackets for the throttle and the TV cables, there is no measurable deflection in the brackets. Should I try to shorten up the accelerator cable, or start shopping for different parts? What would be the best way to take up slack in the cable? The truck is definitely parked until I can get WOT with the cable hooked up.
Thanks for your help.

[Grim 82]

I bent the rod at the back of the pedal and gained some more pull on the throttle cable. Now I can get full WOT with the TV cable attached.

When setting the TV cable with the gas pedal it still runs 1 click shy of WOT. Meaning if I set it with my foot and then go to the carb and push to WOT the adjuster clicks one more position. After manually pushing the carb to get that 1 extra click I can then reach full WOT with the pedal every time. Is this a proper setting or does it need to be set with the pedal only. Like I said, once you nudge it to get that one extra click it will open up fully with just the pedal every time.

[eventhorizon66]

I have no idea why they would suggest shortening the throttle cable as the solution.  Bending the pedal rod, as you did, or moving the throttle cable bracket farther away from the carb (closer to firewall) would correct a problem of limited pedal travel.  When you get WOT with the pedal are you pushing hard into the carpet or is there still a little room between the pedal and the floor board?  If you've got a little room, I would think getting that "one extra click" by pulling WOT at the carb would be OK.  Have you driven it since making this modification?

The test I've aways heard was the proper way to tell if you've got the TV cable setup right is to fully warm the engine, put it in drive, coast up to the lowest speed where the trans automatically shifts into 2nd, then wack the throttle wide open.  It should immediately downshift back into 1st.  If it doesn't return to your garage.

[Grim 82]

I actually removed the carpet for now because the pedal was making a large depression into it, possibly limiting travel. Bending the pedal rod gave me the travel that I need to achieve WOT with the pedal, but I may need to bend it even more to allow room for the carpet and insulation that I plan to put in the cab. The tech at BTO said that 60% of the vehicles that they work on are incapable of reaching WOT without adjustment of the vehicle's throttle cable.

I think that I am getting closer to where I want to be with it. I drove it tonight and it behaved closer to how I think/guess that it should. It holds each gear for a little longer than I like, and upshifts when you let off a bit, which I know is not optimal. When you accelerate aggressively it doesn't seem to like to downshift like you would want it to do when pulling out to pass on a two-lane, but it seems to get better each time I test it. So far I have taken 5 test drives of about 2 miles each since installing it, with the first 1.5 miles just taking it easy and the last 1/2 being a little more aggressive. By the book, the TV cable setting that I am looking for is either what I have now, or one click less. From what I have read here in the archives, it is better to err on the side of a tighter cable rather than loose. If BTO's brackets have the correct geometry I should be in the ballpark. I have heard alot of horror stories, and I guess that I am wondering if I am worrying too much about screwing it up, or if I should just run with it for a while and see how it goes. It's the unseen / no drastic symptoms kind of damage that I am worried about.
Thanks

[Grim 82]

Well I took the pickup to the transmission builder yesterday to have him drive it and sign off on it for the warranty, and got the tv cable set where it needs to be. It's awesome. It's the most well behaved automatic trans vehicle I have ever owned. The shifts are firm and there is no slippage. My ZR2 blazer (which I assume has a 4L60 ? or similar OD trans) shifts all over the place at highway speeds, but the truck locks up anywhere after about 40 mph and it just glides. Then if you stomp it, it downshifts to 2nd pretty much instantly. So far the hydraulic lockup seems to be working perfectly. I was going to put the old 465 in a 76 K5 but after running this trans just a bit I think that blazer might need a 700r4 too.

Thanks guys for all your help on this project. I really appreciate it.

[eventhorizon66]

Awesome, I'm glad you got it all sorted out.

[Grim 82]

I have been having some shifting issues that my trans builder thinks it TV adjustment related, and he's not real impressed by the BTO stuff, so I switched to the Holley bracket p/n 20-121. I also put the stock spring back in. At WOT the part throttle detent valve still sticks out about 1/8". I put a vice-grip on the end of the cable at the carb to shorten it about an 1/8", and then it fully seats the valve. Does this valve need to be fully seated at WOT?
Putting the vice-grip on it to shorten it didn't affect the clicking cable adjustment. Should I make a spacer of some kind to shortne up the cable? Thanks

[Grim 82]

I am still using the BTO plate that goes under the carb to hold the tv cable, and a cheap chrome bracket to hold the throttle cable that attaches with one carb bolt.

[VileZambonie]

How much farther can you pull the tv cable when it's at WOT? What exactly is the trans doing?

[Grim 82]

Holding the linkage at WOT, and then pulling on the end of the cable with a pliers, I can pull the cable that additional 1/8", and then the valve in the trans is bottomed out.

It worked fine for a while and then it started to not want to downshift, like when you come out of a corner and then start accelerating again it wouldn't downshift so it kind of bogged, like a manual in too high of a gear. Then I drove about 45 miles to a friend's place, going 65 on 2-lane, and then it started chugging like an engine miss while going up a hill. I was only a mile or so from where I was going so I kept on until I got there, and then looked underneath and the truck was washed with ATF. I ran a small piece of vacuum hose from the vent on the top of the trans down to the side close to where the tv cable mounts  before I installed the trans. It looked like all of the fluid came out of that vent hose. I checked the fluid and it still read right up where it's supposed to be. At this time reverse did not want to work, and you would have to rev it high to get it to lurch backwards. I let the truck sit most of the day while I sighted in my deer rifle, etc. and then I drove it home again and it was fine. Still not wanting to downshift all the time, etc. but no more overflow problems. It did seem to slip at takeoff a few times. I spoke with the builder and he said that he's never used the BTO kits and every one that he has done with a holley he has used the same part that I just put on, and that I should do the same. So, here I am.....
Does that valve need to be fully pushed in? I think it would be easy enough to take that 1/8" out the cable, but I might be missing something. Thanks for the help

[VileZambonie]

Tighten that adjustment as much as you can but it sounds like you've got an internal leak. How well do you know this builder and what are his credentials?