TrailBeast
AKA Mopars4us on Youtube
I have 2 adjustable normally open pressure switches plumbed to the governor port on a 42RH trans, a relay for each of those circuits, an adjustable normally closed vacuum switch and 2 manual switches to make or break the activation grounds inside the car for each relay.
One of the pressure switches in the governor test port will be set at about 50 lbs, and this one will complete the ground for one of the relays and activate it giving a ground to the 4th (OD) solenoid in the trans at about 50mph.
The other pressure switch plumbed off the governor pressure test port will be set at about 60lbs and will do the same for converter lockup at about 60mph.
This will give me a normal 1-2-3 shift and then at 50mph overdrive will activate, and another 10mph later the converter will lock up.
If the governor pressure drops below 60lbs (approx 60mph) converter lockup will disengage, and slowing to below 50mph the OD will disengage reverting back to 3rd gear.
Now here's the kicker.
The normally closed vacuum switch I mentioned above will allow all the above to happen UNLESS intake vacuum drops below whatever I set it for. (say 7lbs of intake vacuum)
When stepping into the throttle more, intake manifold vacuum drops, so when it drops to the set amount it will open the circuit disabling the relays for OD and lockup causing the trans to downshift back to 3rd.
Inside the car are two rocker switches, and these will break the ground to the solenoids so OD and/or lockup either one or both can be totally disabled manually.
Otherwise the transmission will shift fully automatic up and down through all 5 speeds and kick down when throttle is opened to whatever point I set it at. (like any normal kickdown or passing gear would act) only electrically controlled by the vacuum switch for OD and lockup solenoids, and ONLY if road speed is above that 50 and 60mph where the pressure switches activate from the governor pressure.
The shift solenoids inside the trans have 12v constant keyed power, so I am only working with grounds for all the controllers. (switches and relays) and the manual switches inside the car will be able to override all of it disabling OD or lockup either one or both.
And here's the question.
How do I wire this all up?
Just kidding.
The real question is when it kicks down because of heavier throttle would it make more sense to have it only kick down to OD, or kickdown to 3rd and drop out of OD and lockup both at the same time.
I'm thinking since the truck the trans came out of is a whole lot heavier than the car it's in now that OD should be able to handle the load ok.
Also keep in mind that I will have master control over both gears inside the car, so if I make it where it only kicks out of lockup down to OD, I can still manually make it kick down to 3rd by turning the OD switch off.
Any thought on what "passing gear" should be when in basically 5th gear and it kicks down automatically?
To OD or all the way to 3rd?
Or lockup kicks down to OD and I can kill OD from inside the car if I need more torque for acceleration or climbing a big hill or passing?
Sorry for any brain damage this may cause.
One of the pressure switches in the governor test port will be set at about 50 lbs, and this one will complete the ground for one of the relays and activate it giving a ground to the 4th (OD) solenoid in the trans at about 50mph.
The other pressure switch plumbed off the governor pressure test port will be set at about 60lbs and will do the same for converter lockup at about 60mph.
This will give me a normal 1-2-3 shift and then at 50mph overdrive will activate, and another 10mph later the converter will lock up.
If the governor pressure drops below 60lbs (approx 60mph) converter lockup will disengage, and slowing to below 50mph the OD will disengage reverting back to 3rd gear.
Now here's the kicker.
The normally closed vacuum switch I mentioned above will allow all the above to happen UNLESS intake vacuum drops below whatever I set it for. (say 7lbs of intake vacuum)
When stepping into the throttle more, intake manifold vacuum drops, so when it drops to the set amount it will open the circuit disabling the relays for OD and lockup causing the trans to downshift back to 3rd.
Inside the car are two rocker switches, and these will break the ground to the solenoids so OD and/or lockup either one or both can be totally disabled manually.
Otherwise the transmission will shift fully automatic up and down through all 5 speeds and kick down when throttle is opened to whatever point I set it at. (like any normal kickdown or passing gear would act) only electrically controlled by the vacuum switch for OD and lockup solenoids, and ONLY if road speed is above that 50 and 60mph where the pressure switches activate from the governor pressure.
The shift solenoids inside the trans have 12v constant keyed power, so I am only working with grounds for all the controllers. (switches and relays) and the manual switches inside the car will be able to override all of it disabling OD or lockup either one or both.
And here's the question.
How do I wire this all up?
Just kidding.
The real question is when it kicks down because of heavier throttle would it make more sense to have it only kick down to OD, or kickdown to 3rd and drop out of OD and lockup both at the same time.
I'm thinking since the truck the trans came out of is a whole lot heavier than the car it's in now that OD should be able to handle the load ok.
Also keep in mind that I will have master control over both gears inside the car, so if I make it where it only kicks out of lockup down to OD, I can still manually make it kick down to 3rd by turning the OD switch off.
Any thought on what "passing gear" should be when in basically 5th gear and it kicks down automatically?
To OD or all the way to 3rd?
Or lockup kicks down to OD and I can kill OD from inside the car if I need more torque for acceleration or climbing a big hill or passing?
Sorry for any brain damage this may cause.
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