nurkvinny Posted December 20, 2003 Report Share Posted December 20, 2003 Ok, I have owned about a half dozen vehicles with 700r4 transmissions, 2 4x4s and the rest 2 wheel drive trucks or cars. I currently have a 88 Formula that also has a 700r4. My question is this - why does it shift into 2nd on its own even when the shifter is still in 1st? Not sure if this is a mechanical problem, or if that era Formula shifted this way. I had an 87 GTA that would hold 1st as long as I wanted it to. Is there a secret GM part to correct this? smile.gif Thanks! Quote Link to comment Share on other sites More sharing options...
desperado Posted December 20, 2003 Report Share Posted December 20, 2003 The R4 is programmed to at a specific pressure, regardless of gear position to shift. If you put a shift kit in it this little issue is typically resolved. In fact I believe that B&M sells a kit that specifically states that it will lock out automatic shifting unless the selector is in that gear. It will also allow you to downshift into any gear regardless of speed. You of course realize that most autos will no go into 1st above a certain speed, that kit changes that as well and I think it's marketed as a standard shift kit. Now this isn't a manual valve body either. If you put it in drive, it will auto shift, at the rate that you program into it with the kit. Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted December 20, 2003 Author Report Share Posted December 20, 2003 Thanks... It has an aggressive shift kit installed already (also has upgraded guts and a higher stall converter). After researching this on the net tonight, I have found my problem - and it seems to agree with what you said about pressure. My TV (throttle valve) cable is no where close to being adjusted correctly. The cable controls the pressures, which I guess in turn is affecting the shift points... Quote Link to comment Share on other sites More sharing options...
Dave1647545494 Posted December 21, 2003 Report Share Posted December 21, 2003 yes the tv cable has to be adjusted dead on and its a bitch to get it right sometimes. I had an 89 RS Camaro 305 that someone had swapped a carb onto it tok a whole weekend to adjust the damn cable. Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted December 21, 2003 Author Report Share Posted December 21, 2003 Originally posted by GAS,GRASS,OR,ASS: yes the tv cable has to be adjusted dead on and its a bitch to get it right sometimes. I had an 89 RS Camaro 305 that someone had swapped a carb onto it tok a whole weekend to adjust the damn cable. Same case here... mine also has a carb and the cable wasn't even attached to the carb end when I got the car. I hooked it up, but have not had a chance to adjust it yet. I've only put about 15 miles on the car so far, so I hope I didn't fubar anything up. I've read on a few sites that running without the cable adjusted is EXTREMELY bad for the tranny. I'll get it ironed out when spring rolls around... hopefully in time for the spring Norwalk day (if there is one next year). Quote Link to comment Share on other sites More sharing options...
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