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727 at idle pretty rough in gear

On another slant; but I’d be peeved if the guy you bought the car from made any changes once you agreed to buy it, unless you were in agreement with it. Missing kick the down linkage is a significant ‘change’ and BS…more swapping out the carb IMO. Now you have to buy the linkage and an ‘old’ carb that might have been sitting on a shelf for eons? Just my slant.
 
A&A Transmissions near Indy has reproduction kick down linkage setups. I believe they have special ones for increased height intakes like yours too.
the kick down linkage regulates the internal line pressures in the transmission according to throttle opening. The more the carb opens, the higher the line pressure goes. With no kick down linkage, the transmission behaves as though the engine is at an idle at all times, so has low line pressure, no matter how hard you are getting on the gas. This will cause band and clutch slippage, ruining the trans in short order. Tying the kick down lever back is just as destructive, because the transmission is receiving high line pressure all the time. Pulling the transmission into gear results in quite a jerk, especially in reverse where line pressures are really high. I have seen band anchors broken and the rear band servo blown up due to this.
 
OK so I think I need
  • Carburetor Linkage Stud
  • Carburetor return springs (2)
  • Kickdown Rod
  • Carburetor return spring bracket
Anything I missed? Sourcing the Kickdown rod appears to be the hard part.
 
Ron H said:
On another slant; but I’d be peeved if the guy you bought the car from made any changes once you agreed to buy it, unless you were in agreement with it. Missing kick the down linkage is a significant ‘change’ and BS…more swapping out the carb IMO. Now you have to buy the linkage and an ‘old’ carb that might have been sitting on a shelf for eons? Just my slant.
Click to expand...

I probably don't want to tell you what he did to me on the alternator front! I bought the car on the spot, not sure if he took liberties in the 24 hours he had it afterwards. What can do but move forward right? This is minor stuff at the end of the day.
 
OK I sourced all the parts. Regarding the Intake & Carb, I have an airgrabber hood (69 GTX) I plan on putting on soon. What intake / carb combo would be the right height? I was "hoping" for an Edelbrock Performer intake & AVS2 combo but I'm not sure they are compatible.
 
No kickdown linkage at all? That's scary. If it's been driven a lot like that then I would be concerned about the 727. I use the bouchillon cable kickdown and it's pretty easy to set up.

I always shift into neutral after startup to fill the converter.

I would take care of the kickdown before making a lot of changes.
 
But once you get to the point of intake and carb, you won't be able to use the performer rpm it's too tall for the hood. Try dp4b/ch4b or Holley street dominator if you can find them. Also Mopar m1 dual plane (not the single plane!) which is the same height as stock but in aluminum. The avs2 will work fine you will just need an adapter for the throttle linkage to your aftermarket kickdown cable.
 
SlinktRR said:
But once you get to the point of intake and carb, you won't be able to use the performer rpm it's too tall for the hood. Try dp4b/ch4b or Holley street dominator if you can find them. Also Mopar m1 dual plane (not the single plane!) which is the same height as stock but in aluminum. The avs2 will work fine you will just need an adapter for the throttle linkage to your aftermarket kickdown cable.
Click to expand...

Thanks for the feedback yes the car is sitting I'm waiting for the kickdown linkage to arrive. I don't need a cable its all hooked up until you reach the manifold so I just needed the rod, springs and carb stud stuff. Is there literally no intake in production for the 440 that will work? I can't believe the lack of aftermarket support for these cars
 
If you are trying to keep it stock looking like a 440+6 with the oval air cleaner but with a four barrel, your options are limited on intakes to the ones I mentioned. However, if you don't care about the look of using an oval air cleaner then you might be able to use something like the Edelbrock RPM if you use a drop base air cleaner. I use a drop base now with a Holley street Dom on a 440 with an air grabber 1970 car but have installed an oval 70-71 style four barrel air cleaner too with this intake. The rpm intake is considerably taller though.
 
Notice how much different the recommendations are once you give more detailed info. I would have the whole car checked out by someone who is knowledgeable on these cars.
Just what you have showed is a hack job and shows that the previous owner knew almost nothing about how things work under the hood.
A s said already, no kick down means probable transmission damage. The kick-down linkage regulates the internal fluid pressures of the trans.
Imagine if your oil pump gave the same volume and pressure at idle and 6,000 rpm. Wouldn't last long at high rpms.
Download a service manual on your car. They are free and packed with factory service information.
 
If someone with an understanding of the 727 could look at that video I posted (#29) that would be helpful.
 
ToddMcF2002 said:
If someone with an understanding of the 727 could look at that video I posted (#29) that would be helpful.
Click to expand...

That video doesn't tell us anything other than the lever works and it's connected to the kickdown. You have to have a video while pushing the gas pedal or pulling the throttle linkage at the carb. Basically at idle the throttle lever you show in the video should be almost all the way forward but with some tension back towards the rear of the car, and at WOT it should be all the way back. Maybe set up your phone or a GoPro down there at the trans while you work the throttle.
 
The action shown in that video looks pretty typical but the critical thing is adjustment of the upper linkage. Do you have a factory service manual? It describes the procedure for adjusting the linkage. Basically the lever on the transmission should be wired fully back and the upper linkage adjusted to meet it with the carb throttle held wide open. The adjustment should allow for the carb throttle to go full open but not quite fully bottom the transmission lever. That’s very general - more explicit adjustment details are in the manual or can be searched for here.
 
SlinktRR said:
That video doesn't tell us anything other than the lever works and it's connected to the kickdown. You have to have a video while pushing the gas pedal or pulling the throttle linkage at the carb. Basically at idle the throttle lever you show in the video should be almost all the way forward but with some tension back towards the rear of the car, and at WOT it should be all the way back. Maybe set up your phone or a GoPro down there at the trans while you work the throttle.
Click to expand...

I just ordered all the topside linkage yesterday. All I'm trying to confirm is that the lever is articulating correctly - in other words is its bounce back behavior as expected. I'm not familiar with the 727 but I've verified that my linkage looks like this reference pic I found - except the rods up to the manifold are missing in this pic

IMG_1572.JPG
 
AR67GTX said:
The action shown in that video looks pretty typical but the critical thing is adjustment of the upper linkage. Do you have a factory service manual? It describes the procedure for adjusting the linkage. Basically the lever on the transmission should be wired fully back and the upper linkage adjusted to meet it with the carb throttle held wide open. The adjustment should allow for the carb throttle to go full open but not quite fully bottom the transmission lever. That’s very general - more explicit adjustment details are in the manual or can be searched for here.
Click to expand...

Thank you that was actually helpful. I realize people want to offer opinions and criticisms but if they read this thread they would know I ordered the kickdown rod and springs etc last night. All I was trying to do was verify that my 727 kickdown lever behavoir was as expected. Sounds like it might be good. I had a Cuda prior to this car so I'm familiar with the topside kickdown rod function at least. And yes I have the service manual (as others have suggested) I just like to get realtime input. After all that should be the purpose of this forum.
 
I’ll tell you that the service manual adjustment instructions are a little confusing to me - maybe I’m just dense. What has seemed to work is what has been discussed on the forum by some. It’s to adjust the linkage so that with the throttle wide open against the stops, the transmission lever is just short of being fully open (to the rear). I get proper full throttle kick down action so I figure it must be close.
 
AR67GTX said:
I’ll tell you that the service manual adjustment instructions are a little confusing to me - maybe I’m just dense. What has seemed to work is what has been discussed on the forum by some. It’s to adjust the linkage so that with the throttle wide open against the stops, the transmission lever is just short of being fully open (to the rear). I get proper full throttle kick down action so I figure it must be close.
Click to expand...
That's very clear thank you. I found an OEM adjustable threaded kickdown rod on eBay just waiting for it to arrive. I'll follow this guidance.
 
The other important part of the adjustment is when the linkage is at rest with throttle blades closed. The kick down lever must not be under any pressure, with a little bit of free movement. If this is not the case, the transmission will not downshift to LOW when the car is at rest, as at stop light, etc.
 
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