1966 Avanti

[mfg]

7 hours ago, Zedman said:

 

That’s it… I have an ‘off-on’ toggle mounted on driver’s side console within easy reach.

The lockup disconnect at rear of stop light switch is still functioning.

My normal driving routine is to not lock the converter unless I’m on the highway, or higher speed secondary road.

As I remember, the problem I found with the factory computer controlled converter lockup was that it locked to early… at too low an engine RPM causing what I can best describe as ‘lugging’.

I heard many years ago that not allowing the converter to lock up automatically would damage the converter by overheating it…. In 15 years of manually controlled lockup, overheating has never happened… 

ALSO…. I believe the simplest way to accomplish this, if your Avanti has CCC, is to install toggle into the converter lockup switch wiring (at rear portion of stoplight switch)….located at brake pedal.

Edited September 26 by mfg
Added text

[mfg]

8 hours ago, Zedman said:

 

In addition… no extra holes to drill!..… The factory screw which retains console side upholstery can be utilized to support toggle switch by crafting simple ‘L’ shaped bracket.

[Zedman]

On 9/26/2025 at 11:09 PM, mfg said:

In addition… no extra holes to drill!..… The factory screw which retains console side upholstery can be utilized to support toggle switch by crafting simple ‘L’ shaped bracket.

Thanks for that idea and the TC lockup info, MFG. 

[AG-R3]

I was out of town for a week, are we still talking about this here?

My RQA original came with a 350/300, with a "Powershift" transmission, which was later described as a Ford FMX by a Mechanical associate.  The Quadrajet was replaced initially by a Holley Economiser 4 barrel during the 70's gas crisis.  It was a bit less  performance wise, but the roar of the Quadrajet rear barrels opening was gone and the mileage was up considerably.    In the 90's, the car was totally refitted, with the body off the chassis and a Jasper 350/330 and T700R4 were installed. 

During the cleanup of the install,  I found out that using an Edelbrock with a 700R4 was not going to work properly unless you manage the TV cable properly.  The TV cable  did not attach to the Edelbrock throttle linkage correctly, which threw off the arc geometry required to satisfactorily shift the transmission.   The fix for this issue was to buy a kit from an outfit named Bow-Tie OD, which included an oval cam that the cable rested on....  and the cam was moved to various positions initially to emulate the proper GM arc to make the cable act on the TV pressure as required.  There was also a new spring for the TV cable and that had to be inserted inside the pan, so the pan had to come off and you get to know you transmission really well.   The TV cable was another aftermarket brand  and I made the mount where it locks in the setting.  

Opening up the transmission shows how the lockup was controlled by wiring +12 to the Lockup solenoid  using a brake light switch in the 3rd gear oil gallery.  Once the governor determines it was time to use 3rd, the gear change was smooth and then then engine dropped another 2-300 rpm or so, when it locked up.  When it dropped out of 3rd, the lockup went off.  So after the transmission install, I ran a +12 with to the assigned "weatherpack" connector on the side of the transmission and that was it. 

Once the Bow tie kit was installed, you raise the car on 4 jack stands, have a Transmission pressure gauge fitted to a port, just  forward of the shifter lever, start the engine and allow it to warm up, then call the tech line at Bow Tie OD.  Once assigned a tech support person, he instructed me to put the trans in 1st and let him know what the TV pressure was.  He responds with "tighten" or "loosen" the TV cable at the adjusting point, then it gets a little hazy here as the 1-2 shift on my car happens in the blink of an eye, but I know we went through all 4 gears and once he was satisfied that the TV pressure engaging each gear was satisfactory, he said " it was good to go".  It was obvious that you want to "feel" each shift just slightly.  

I was always worried about the trans overheating, so installed a temperature sender in the oil pan and the gauge went right below the speedometer.  The temperature would always hang between 160 and 190 on the road.   

  So after driving it for a number of times, I did not like a few things, the first being the 1-2 shift.  Since the car has a 3:54 axle, you'd better not have a cup of coffee in your hand when you depart or you will be wearing it.  Another thing is that there is no way to avoid the 1-2  shift, as you cannot start out in 2nd, unless something has been recently  developed to do just that.

 Another issue is that when this car gets to 4th and in OD, the engine is turning about 2200 rpm, but it seems like my engine is lugging or struggling with something and is not smooth.
This is what tempted me to get into the transmission pan and see how thing are set up. The trans pan itself is a deep finned aluminum style and it holds about 3 extra quarts.  Somehow I think back that this had to do with the temperature thing.   With the pan off the filter is easily removed and the wiring inside  is obvious and fairly simple.  The important part is that there are  Oil galleries for 2nd, 3rd and 4th gear.   You can put the switch in any one of these and have the lock up 2nd, 3rd and 4th.....  or 3rd and 4th  or just 4th.
I elected to install a SPST switch on the dash and split the +12V supply to the solenoid, to see what the impact would be by driving without the OD.     Understand that 4th gear is .66:1 or the like and the power required to force trans fluid through that myriad of blades and orifices of a torque converter to enable OD, can cause the temps to rise pretty quick.  I actually watched the temperature needle go from 180~ up past 240 in say 30-40 seconds.   When the lockup switch was thrown, the temperature went back down just as quickly.  
 There is a schematic that uses a brake light switch and a vacuum switch inline with the power supply to enable an automatic engage/disengage.  There was even an article in an AOAI Quarterly a number of years ago, outlining this procedure. (see pic enclosed)