LZ overdrive in a av8 model A. Anyone tried this?

[28fordroadster]

I found a 41 LZ overdrive that is almost complete. I would like to drop it into a roadster pickup. Yea I’m mainly concerned with getting the od to operate. I assume that the clam for the closed drive will bolt right up. The cross member should not be a problem. Can I use a truck three on the tree? I’m thinking 4/11 rear gears. I don’t have the solenoid. I’ll want the stomp on the pedal down shift feature. What am I up against?

[Ken/Alabama]

The driveshaft and torque tube will need to be shortened. You’ll need the solenoid,Governor, kick down switch, relay and the overdrive cable. Also probably make a new transmission mount.

[28fordroadster]

Yep I should have been more specific on the trans mount and drive shaft. I knew it would have to shorten it and fab a mount. It the switch, solenoid, and relay that I know little about. Any input would be appreciated. It looks like vanpelt lists a wiring harness. If anyone has a solenoid please let me know. Thanks again

[28fordroadster]

Looks like I need a governor and cable as well

[Mac VP]

The 40-48 LZ overdrive solenoids had a much longer operating plunger so you must stay with this type on those transmissions. They were only made in 6 volt configuration so the vehicle would have to be a 6 volt system. The operating relay (which was also uniquely Lincoln) was also 6 volt. The governor and the kick down switch don’t care what the voltage is. We may have a useable LZ 6 volt solenoid but we’ve never had the relay for some reason.

You’re aware that these were sideloader transmissions and the shifting was accomplished by a steering column shifter mechanism. So you’d have to get that figured out too.

[PeteVS]

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I don't know what any of these SOLENOIDs look like but I did work for many years designing SOLENOID valves. These valves are made in several voltages using similar coils with different number of turns and wire size. The rule of thumb is that if one is changing a coil design from one voltage to a voltage of twice that voltage, one increases the AWG of the magnet wire by three (AWG numbers double the cross sectional AREA when you decrease the AWG by three) and then doubles the number of turns. For example, if a coil is designed for 120V and has 200 turns of #22 wire, a coil for 240V would have 400 turns of #25 wire. The same technique applies to halving the voltage but number of turns is reduced and AWG of the wire is increased.

If the coil seems to be fairly easy to disassemble and strip off the wire, remove the wire and count the number of turns, weigh the wire that you've removed and measure the diameter of the wire. Then, buy new wire (Be sure to get the same weight of wire.) at the proper size and rewind the coil using the same terminating techniques as the original.

Also, realize that magnet wire is just copper wire that has a coat of varnish. The thickness and exact type of varnish are directly related to a coil's life at elevated temperatures. At high temperatures, caused by both ambient temperature and heat generated by current passed through the windings, the insulation will fail, the turns will short out and the coil will die. So, if possible, stay with as good a class of wire as you can.

[pistonbroke]

Hey Mac, I've been overdriving just about all my old stuff with these warner units. I'm wondering what the difference is with the LZ relay compared to all the rest? I have one in my spares box that is a little different and thought it might be what is needed for this app.
Tim

[Automotive Stud]

I've got an LZ overdrive under my workbench, I also have a model A roadster with a '49 Merc OD in it with Zephyr gears in it, which is open drive. As Mac said, the LZ overdrive solenoid is LZ specific and has a much longer shaft than the one used by most other Borg Warner overdrives.

I was going to put my LZ trans in my '40 but I didn't want to modify the crossmember, I wound up using a BW overdrive mounted in the torque tube. Assuming you can fit the transmission in the chassis, you'll have to shorten the torque tube obviously to fit. The wiring can be done factory style or you can install a simple toggle or push/pull switch to engage the solenoid, which you could simply flick off to downshift while accelerating. Either way you'll need a good LZ solenoid, which as Mac said are only 6v.

[rotorwrench]

The common operating solenoid was 1-inch from the edge of the alignment flange to the very tip pf the shaft. Convertible models with the special adapter were 1 1/2-inch in length. There were longer ones in odd applications which could be 2-inches long or longer but they are not common and due to the way the solenoid mount was made on the Lincoln unit, I'm afraid that the solenoid is in the Odd category. I don't have the prewar Lincoln parts catalog so I can't help but a person will need that part number to find the correct part. If a person has a piece of rod that can be inserted through the solenoid seal and bottomed out in the pawl socket then a rudimentary measurement of length could be gained. This old HAMB link has a photo where the length can be seen on the solenoid for a prewar Lincoln Continental.
https://www.jalopyjournal.com/forum/...s-info.139084/

The 1941 thru 48 Lincoln unit is nearly a foot longer than the early V8 transmissions. The torque tube would have to be shortened a good bit for fit. These transmissions have close ratio gears so a person would have to use a rear axle ratio that would work well with it. Lincolns had their own distinct clutch actuating mechanism as well. The reverse lock out set up is important so all that stuff has to be there too.

[Fred A]

I ran an LZ overdrive in a '40 behind an Olds Rocket engine. I went for the 4.44 gears in the rear. The overdrive had a 19/25 gearset in the trans. The combination was wonderful for the gearing, but tough on the X member. I put a lot of work in the chassis. Luckily the '37-'48 drivelines are easier to shorten. When I went to bigger tires, the old trans could not take that 371 J2 power and killed the car. Next owner went to B&M and a full floating rear. That may have finished the whole thing after the frame mods. A boxed Model A could take the beating. Good Luck: Fred A

PS: The solenoid is two stage with a high and low current for cruising. I matched that stage resistance with a resistor and never a problem. Resistor must take the peak current rating to survive.

[Frank Miller]

Any relay that can handle 20 amps will work. The overdrive engages through a grounding circuit activated by the governor and the kickdown switch. I'm not sure if that has the reverse lockout switch or not. Ford saw no need and eliminated it in 51 and told dealers to bypass it on earlier cars if it was bad.
The key o getting it to shift out is the circuit that grounds the points. The automatic kick down requires the engine stall for a few revolutions while the solenoid disengages the overdrive. When it shifts out the grounding circuit opens via the solenoid. You do not even feel it.The engines does not really stop but the torque is removed from the input shaft.
You will be fine with 4.11 gears but if you have something like 3.78 already installed I would go with those. You have a light car and you'll do fine with the higher ratio. Got 3.78s in my 49 convertible and have crossed the rockies a few times with my stock 8ba. Yes, I kicked out the overdrive on a few hills.

[Kurt in NJ]

the solenoid has 2 windings in it, pull in winding, and a hold winding, and a switch to turn off the pull in winding.