Slant Six A/C throttle linkage or Cable...why?

Slapping a factory a/c (knee knocker) on a 66 Valiant. Got it bolted up no issues. But the owner said something about needing to use a throttle cable and not the linkage. So I break out the handy dandy 66 service manual, and it's showing two types of linkages.

#1: why? Is there an issue with using the throttle linkage?

Car is a 66 Valiant, originally non a/c and auto trans. What will I need to make this happen? Got the condenser, all the lines, pump, brackets and idler pulley.

What the deal might be - a 1966 - I thinking - was the first year of the factory dash unit that Mopar would carry through the end of the A bodies. The early units were - like you have - dash hung units - would believe it's in the floor mount area that there might be interference with the 1966 factory air versus a drop down dash unit.

in the days of saving a nickle per car, why they didnt adopt the cable throttle earlier is a mystery. look at that thing!

I dont have exact answer. One would probably have to install the factory air components to discover the conflict with throttle.
That type of all rigid mechanical throttle linkage is/was fine for a push/pull lever in industrial application ( where it came from ) but it never was safe in a vehicle. In early automatic trans builds the throttle pressure linkage didn't have the slot for free throttle return either. Collisions or just a broken motor support would adversely effect these linkages.
There's a lot of stuff they wouldn't spend the money to re-engineer before designing a whole new generation. Then they went hog wild and engineered knee protection ( lower dash pads ready for 68 model production ). And that was immediately followed by the DOT lap belt mandate. DOH!
Anyway...
I would replace all that with 67 and later, firewall mounted pedal and all, a/c or not.

looks just like the V8 gas pedal in the illustration. I doubt the cable is the same though. the V8 cable is pretty short.

Deemo said:

#1: why? Is there an issue with using the throttle linkage?

Car is a 66 Valiant, originally non a/c and auto trans. What will I need to make this happen? Got the condenser, all the lines, pump, brackets and idler pulley.

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No problem using your mechanical rotating rod throttle linkage with your knee knocker. The dealer (or suppliers like Sears) did not change out the manual throttle setup (too expensive!)

stillrunners said:

What the deal might be - a 1966 - I thinking - was the first year of the factory dash unit that Mopar would carry through the end of the A bodies. The early units were - like you have - dash hung units - would believe it's in the floor mount area that there might be interference with the 1966 factory air versus a drop down dash unit.

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65 was the first year of the factory integrated heater/AC. The limited area available in the early A made the rotating rod assembly occupying some of the space with the AC part of the system. For slant-equipped cars with factory AC, the Solution was to use the less intrusive cable setup for the V8. Additionally the horizontal bulkhead connector opening on the firewall was also a problem trying to occupy real esstate with the factory AC unit. The factory solution was a new firewall for both V8 and slant cars that were coded for the factory AC. Besides the obvious various openings for the AC part, the firewall got a larger heater blower motor opening AND the bulkhead connector opening was changed from horizontal to vertical and moved just a bit to the left from where it was. Now the bulkhead connector and AC unit weren't trying to occupy the same space!

RedFish said:

I dont have exact answer. One would probably have to install the factory air components to discover the conflict with throttle.

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This is what I found when mocking up the factory AC to a regular slant firewall!

Redfish said:

Anyway...
I would replace all that with 67 and later, firewall mounted pedal and all, a/c or not.

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The 65/66 factory bolt in throttle cable bracket shows up quite often for sale. The early pedals used with it are now available as a repro. Personally I would rather use the factory cable throttle bracket rather than adapting the later setup.

vitamindart said:

looks just like the V8 gas pedal in the illustration. I doubt the cable is the same though. the V8 cable is pretty short.

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On the factory cable setup whether for the slant or V8 the oedal is the same, and now available as a repro. Yes, the cable length is different.

65 Dartman said:

No problem using your mechanical rotating rod throttle linkage with your knee knocker. The dealer (or suppliers like Sears) did not change out the manual throttle setup (too expensive!)



65 was the first year of the factory integrated heater/AC. The limited area available in the early A made the rotating rod assembly occupying some of the space with the AC part of the system. For slant-equipped cars with factory AC, the Solution was to use the less intrusive cable setup for the V8. Additionally the horizontal bulkhead connector opening on the firewall was also a problem trying to occupy real esstate with the factory AC unit. The factory solution was a new firewall for both V8 and slant cars that were coded for the factory AC. Besides the obvious various openings for the AC part, the firewall got a larger heater blower motor opening AND the bulkhead connector opening was changed from horizontal to vertical and moved just a bit to the left from where it was. Now the bulkhead connector and AC unit weren't trying to occupy the same space!



This is what I found when mocking up the factory AC to a regular slant firewall!



The 65/66 factory bolt in throttle cable bracket shows up quite often for sale. The early pedals used with it are now available as a repro. Personally I would rather use the factory cable throttle bracket rather than adapting the later setup.



On the factory cable setup whether for the slant or V8 the oedal is the same, and now available as a repro. Yes, the cable length is different.

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That's about the answer I was expecting and looking for. I have noticed some blower motors wet bigger in pics compared to mine. And now I know why. I'll look further into the firewall differences as well. That is actually some very useful information that I was unaware of until now. Thanks for the responses, now I can go forth and find me some parts!!!

Deemo said:

That's about the answer I was expecting and looking for. I have noticed some blower motors were bigger in pics compared to mine. And now I know why. I'll look further into the firewall differences as well. That is actually some very useful information that I was unaware of until now. Thanks for the responses, now I can go forth and find me some parts!!!

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Your heater blower motor will still be fine when using a knee knocker with it's own blower motor. It was when using the factory integrated system that the heater-only blower motor was not adequate enough - hence the larger motor. With the knee knocker you don't need to change the rotating rod assembly (I would change to the V8 cable style) nor change anything to do with the bulkhead connector opening. I am adding OEM factory AC to my wagon and ended up changing the firewall to an AC firewall to accomodate the changes that are required. Take a look at my wagon thread for when I was working on the firewall and you can see the differences in the non-AC and AC firewalls.

I should also mention that the limited real estate in the early A engine compartment necessitated a drier that was mounted horizontally on top of the passenger inner fender. The more common vertical driers tended to share real estate with the alternator and horns. That all changed with the wider 67 so more traditional components could be used.

65 Dartman said:

Your heater blower motor will still be fine when using a knee knocker with it's own blower motor. It was when using the factory integrated system that the heater-only blower motor was not adequate enough - hence the larger motor. With the knee knocker you don't need to change the rotating rod assembly (I would change to the V8 cable style) nor change anything to do with the bulkhead connector opening. I am adding OEM factory AC to my wagon and ended up changing the firewall to an AC firewall to accomodate the changes that are required. Take a look at my wagon thread for when I was working on the firewall and you can see the differences in the non-AC and AC firewalls.

I should also mention that the limited real estate in the early A engine compartment necessitated a drier that was mounted horizontally on top of the passenger inner fender. The more common vertical driers tended to share real estate with the alternator and horns. That all changed with the wider 67 so more traditional components could be used.

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Yes, I have all that stuff ready to mount. The dryer has holes that are pre marked by the factory. Like I said. Was worried about the cable. And I'll look up your thread on that. Don't think we will go that far with this one, but I may do it to my 65 if it's not difficult

Deemo said:

Yes, I have all that stuff ready to mount. The dryer has holes that are pre marked by the factory. Like I said. Was worried about the cable. And I'll look up your thread on that. Don't think we will go that far with this one, but I may do it to my 65 if it's not difficult

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Dartman - I stand corrected....seems I did have a 1965 4 door Val with the dash controlled factory air unit....I've had lots of 63-66 with the dealer installed though.....

RedFish said:

That type of all rigid mechanical throttle linkage is/was fine for a push/pull lever in industrial application ( where it came from ) but it never was safe in a vehicle.

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My 1985 M-B 300D uses a rotating rod "throttle", and they were considered a safer car. My 1969 Dart's gas pedal would occasionally stick (stuck cable) and I would have to tap it to come up. Unsafe are all the drivers today who don't even think to turn off the engine, or shift to N.