3x2 to 700r4 TV hook up

I have done the search, and have seen the 1-800 hot rod sources for this, Bow tie overdrives..ect..
I dont care for them., and they are a bit pricey, and have heard some of them just dont plug and play well with out a lot of work....
so whats the point of spending 270 bucks to have to go and modify your shit anyways?
I would like to see how others have cured this situation. Im aware of the ratio and degrees on the belcrank and all and why, but would like to see your own cure for the "just buy it" crowd.,please explain it well enough to do the job, I hear these 700r4's are touchy and dont like to be adjusted incorrectly or have their TV cable pulled wrong.

Im running rochester 2g's and would like to see how to modify the bellcrank to accomidate the TV set up.
Thanks all

 

I ran a 383sbc with trips hooked to a 700R4. My tranny guy made a crescent-shaped piece (he has a pattern for it) with the correct radius/arc to operate the finicky TV on the trans. Apparently he's done so many of these that his kid sat down and designed this bracket that bolts to the center carb lever. Car has been sold, so I cannot provide a photo.

dj

 

The key to getting the 700-R4/200-4R to operate as it should with a carburetor it was not designed to operate with, is the proper throttle shaft to Throttle Valve (TV Cable) cable ratio...or turning radius. With out the proper turning radius at this hook-up point, the transmision will never operate properly. You will need this http://bowtieoverdrives.com/Instructions.htm (click on Rochester tri-power small base or large base) and you will need to follow these instructions http://www.chevyasylum.com/tech/tvcable.html ...ESPECIALLY the last paragraph.
I chased info on how to set up my TV cable adjustment for WEEKS, and nothing did the trick...until I read the last paragraph on the Chevy Asylum Site. Took me faster than it takes to type this, to do the cable adjustment. The transmission shifted perfectly, and I haven't touched the adjustment since...

 

I just ordered a bracket from Jeg's that is made for the Edelbrock 650 carb. It was $25 and looks like it can be easily adapted to most setups. I also had to buy longer studs and a 1" spacer to get the carb higher for the bracket to line up. Both TCI and Bowler wanted big bucks for their kits.

 

I need more than this..
I am looking for the information and pictures on how someone modified their Bell crank on the center carb to accept the cable in the correct arc. not with a Kit.I have seen and read the bow tie overdrive stuff and their kit is too expensive for just a dam TV cable set up..it cant be this hard.

adjusting the cable will probably be the easy part, its all the brackets and the correct placement of the TV cable pull pin on the carb butterfly bell crank that i would like to see other peoples ideas and what they have done

 

any pictures?

 

http://www.transmissioncenter.com/700r4_Throttle_Valve_Cable_Adjustment_Instructions.htm

reading up on this..it gives some dimensions that could be a guide

 

Plenty of early 80s vehicles still used 2 barrel Rochesters...I would think that you could find a mid 80s Firebird or Camaro with a V6, or a mid 80s truck, and rob the brackets and linkages off of it. The later carbs are feedback style, but the linkages should be similar.

 

nothing earlier than 90's live in these parts..at least not many older vehicles
due to the cash for clunkers and the past administrations boondoggles for the same out come has really diminished the 70's and 80's vehicles in our bone yards up here. its really hit or mis..and lately more mis than hit.

still a good idea, i will keep looking out for them

 

I'll check around here...we still have plenty of older stuff in the yards. It will be next weekend before I have time though.

 

Thats cool,
hey thanks a lot
Im in no big hurry..next week is cool.

Im looking to find something before i tackle this part of things, let me know what you find.

I'll see what i come up with

 

I did mine different.... how I hooked up my 700R4 to inline Dellortos: I calculated out the cable pull ratio at the pedal, drilled an extra hole, ran the cable snap fitting into the square hole I routed out in the firewall with a Dremel and connected it to my throttle pedal. Still has the adjustment where it ratchets like factory. Shifts great, 1800 miles on it so far.

 

Pictures?

 

Try page 13 of the attached PDF, it has the arc angles and dimensions required.

 

Thank you ..Thats what i was looking for.
a ton of good info.

anyone out there retro fit their 2g's? for this set up?
there has to be someone.

 

I used 3 small base rochesters ordered kit from vintage speed (speedway motors also carries) for 3x2 conversion . this comes with a longer shaft for centre carb . the shaft is machined to bolt on a throttle bracket . on mid 80s Q jet (with tv cable) the bracket is installed on shaft and the end is peened (hamered) over . grind off peened metal . the bracket will come off and bolt on the shaft in this kit . I had to weld on a tap and drill hole for accelerator pump arm also just as important modify bracket for cable to mount on intake . I needed 4 inches from mount bracket to tab for cable to clip on . some cables are different with different measurements . I also had to cut bracket off OE rochester throttle bracket for idle speed and weld on Q jet bracket . after some tedious work it was worth the effort . car runs great

 

Wow..that seems like a lot to go thru just to hook a TV cable to a bellcrank.

got any pictures

with Algoma56 information i may be able to make changes to the existing belcrank and add the stud where its needed.
just need to make a full scale drawing of it and place it on my center carbs arm and go from there..add or drill where necessary.

 

I will be needing to do this soon. Here is some info I have found.
http://www.purplesagetradingpost.com/sumner/techinfo/700R4p1.html

 

Thanks Cretin,
the more info the better.

anyone running a 700r4 want to show us how you did it?

 

Just find an early Astro van w/700r.They have nice intake manifold brackets and you can cut the bracket off the carb and use it also.I was unable to just bolt on with my application.The internal cable must have a preload of about 1/8" then you can do the final adjustments with the outer cable.This is how I did my 250 inline and have 3000 miles on it with no problem.

 

I built the linkage on this 348 Chevy using three Autolite 2100 carbs. I had to leave provisions for a 700-R4 tranny. I bought the 700-R4 "foot" that bolts to a Holley carb and duplicated the geometry on the Autolite carb using the throttle shaft centerline as a reference. It works awesome.

 

now i might be able to come across an astro van, Thanks for that suggestion..i'll keep my eyes open, any ideas of the year i should look for?

 

any more of us out there?
more ideas and pictures?

 

Here are some shots of how we hooked up a 700R-4 with three Stromberg 97's. In one of their discussions, Bowtie Overdrive indicates that the key is to make sure that at WOT the TV cable is extended fully. The only real way to do that, I think, is to have the trans pan off and see if it is fully extended when the throttle pedal is floored. Here is how the finished design worked out for us. So far no problems. Jim M

 

Von Rigg Fink, you're right, its not that hard.
I made an adapter gizmo I bolted on, using the purplesagetraingpost diagram and instructions. They'll work for any carb, or series of carbs. once the linkage is right, buy a universal replacement cable, because they don't have a set length from the stud to the bracket.. Set it for full pull on the cable is full throttle on the carb. Then, the part most folks miss. With a pressure guage in the pressure port in the trans (drivers side a few inches above the shift mechanism), and the cable disconnected, car idling, find your "idling pressure". Mine was 80 psi. Now hook the cable back up, with the adjuster out towards the carb. Push the adjuster in, lengthening the "sheath" of the cable, until the pressure rises 2 or3 pounds. You're done. You can go a click or two on the adjuster either way from here, but no more. The "start point" of the cable pull is just as important as the "full pull" point.

I'm not a trans guy, but I managed to figure it out. You can too.
Ralph

 

I seem to remember reading that the geometry of nearly all Rochester carb bell cranks were the same and correct for what is needed with a 700r4. I'd guess that if that is true all one would need to do is figure out which hole to install the correct stud in and mount the cable housing. I guess it kinda figures GM would design the trans tv cable pull geometry to work with the carbs they already had. No first hand experience mind you, but it does kinda make sense.

 

Thanks Hyperfe, Ralph & CayoRV
I think im going to make up a template out of thin stock and mark out the pull angles and radius for the pin. and see how well and where it lines up with my original belcrank..I agree Cayo , its probably allready there, or just needs a hole drilled in that certain spot.

keep the pictures coming guys..the more ideas the better.
I will be doing the final adjustments with the pressure gauge

 

There may be some ifo in this link?

http://purplesagetradingpost.com/sumner/techinfo/700R4p1.html

 

409Deuce, you're a bit late to the party. That site's been referred to twice in this thread already! Good info though. It worked for me.
Ralph

 

Here you go Von Rigg Fink, here's my homemade BowTie copy. I put the car on jack stands and did the whole pressure guage test through the gears. A LOT OF MONKEY MOTION! I hope the really low first and overdrive will be worth it. Good luck on yours. Troy