I am getting ready to put a Chevy 700R4 trans onto an old motor and I was told that the 700R4 requires electronics is this true? Is ther an off the shelf item for this? Can someone please explain! Thanks
Did you search? This topic comes up fairly regular, they need a switch for the kickdown and you have to be sure the TV cable geometry is right, it's hooked up and adjusted properly, or you'll roast the trans in short order.
you only need an on/off switch to engage the lock-up torque convertor that's it,many companies sell the switch ...TCI,PATC i think even PAINLESS makes one too..Summit sells em they're like 135.00.You need a computer if you have a newer 4L60E trans since all the shift solenoids are controlled by a computer but GM sells a stand alone computer for those as well for carb controlled engines they can get pricey if they have a programmable PROM chip though plus the software to tweak
A 700r4 only "requires" electronics if you use a lockup converter. My '33 doesn't. Mine has a 2800 stall converter and works fine without the lockup. The builder built both the converter and transmission so he knew what was needed and also knew the combination used in the car. If you do use a lockup converter, you will gain some mpg when out on the road but won't see much difference around town. There are several sources for a simple wiring setup on the web that uses your brake light switch in the circuit if you want lockup in high. Just be sure to use a LOT of cooler and have the throttle cable adjusted correctly. Depending on what you want to spend, TCI makes a valve body that maintains a constant pressure that eliminates the "issues" with the cable adjustment. The 4L60E is the same transmission except it uses a computer for control (both lockup and shifting).
No electronics needed for the 700R4. Just needed to wire the connector on the left side of the transmission to 12V power and the other to ground using the brake switch as an interrupt. Google bowtie overdrives they have tech faqs etc.
Call up these guys, they will let you know what you need. http://www.bowtieoverdrives.com/index.shtml
the lock up unlocks once you go below 35 so i never bother with rigging it to a switch, works good for me
it's a Throttle Valve switch,not a kickdown like in the TH350.it regulates line pressure to the valve body and yes make sure it's adjusted correctly or you'll lose 1st and 3rd real quick!.Most TV valves are adjusted improperly causing failures in the 700R4,due to low line pressure. Summit sells a TV cable geometry bracket that ensures adequate enough line pressure thoughout acceleration and highly recommended and easy to install,also make sure you get a 700R4 convertor they cost a little more,and if your running 350+ HP i recommend a "BEAST" reaction sun shell,one of the major weak points in the 700R4 and additional clutches in the 3-4 clutch pack,preferrable RED ALTO i was an ASE/GM factory trained technician for 7 years,and******* guy for 5
I used a toggle switch on mine so I could turn the lock-up off for around town. It was sweet on the hwy. 70mph at 2 on the tach. There is a company on ebay that sells an inexpensive kit with the plug harness and a new cylenoid( I can't spell) for cheap. I cant remember the name of the company, I put mine in a couple of years ago, but Ill see if I cant dig up a reciept. Or you can just do a search for 700r4 lockup kits and they should come up. They sell alot of other stuff as well to beef up that 700.
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