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Stall converter for push button 727

MWFan

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The 1964 Polara I just bought has a push button trans. The motor is a 440 built to 1970 Magnum specs. It has a little Edelbrock 600 carb and in the paperwork that came with it was an email sent to the previous owner by the guy who built the car explaining that the small carb was because you cant get a high stall converter for the early 727 19 spline input shaft to overcome the carb bog of the larger CFM carbs. It seems like there should be a happy medium? Would a 650CFM carb help much? I know the 440 Magnum came with a larger carb. Anyone have any suggestions? On the highway when you stick your foot in it, you can feel the little 600 choking the potential of this motor.

Thanks, Bernie
 
Hey Bernie. Have the transmission rebuilt with the later input shaft etc. transmission parts that will allow the use of the later, much more plentiful varieties of higher-stall converters. Should be lots of info here as to what parts are needed. It's a pretty straightforward job. Been many years since I did one myself, but hopefully will be doing one again soon for my '64 Polara convertible.
 
I would think it's starving for more juice with a 600 on it. Definitely check your plugs. I'm running two 600s on my 440 hooked up one to one. Mild cam, 9.3.1 compression.
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I had a 19 spline tc reworked for a higher stall but I can't tell any difference. (Push Button) They say they can't get much more out of them. Replacing the input shaft is the only way to go in order to have your pick of newer converters.

I'm useing a 3.23 gear out back and you can see how this converter and engine works. I'd like to have a better converter but it is what it is for now.
 
There's places around that will rework the 19 spline. But there is a much bigger selection of converters if you swap a later model input shaft and reaction support in. 1967-1970 is a bolt in deal. Takes less than 1 hour when the trans is out.
Doug
 
Thanks guys! I guess I should have titled this thread differently. What I really was looking for was a carburetor that would improve flow with minimal bog. The old Carters apparently worked OK with the pushbutton 727 behind a 426 Wedge, are they available, or what is an aftermarket alternative other than this tiny 600CFM Edelbrock? I am not going drag racing, just looking for a less choked down carb.
 
I'm speculating a bit here, but would suspect you've more going on than just the CFM rating of the current carburetor on the engine. Generally a smaller carb would make the car more responsive off idle, but there are always exceptions. Things to consider: accelerator pump shot, secondary opening point and in the case of the Eddy you've got those wonderful step up rods and springs which work together to manage fuel flow.

Personally I've not had good luck trying to fine tune that style of carburetor, but I'm sure there are many who can do it in their sleep. Changing the secondary opening point is more involved than a Holley and the combination of jet and step up rod contour was never intuitive to me.

I've had better luck with Holley, where you can change the accelerator pump cam, the size of the pump shot, power valve, main jets and easily change secondary springs to control when they open. Usually a bog would occur when there's more air than the engine is ready for, meaning the secondary's have opened too soon. I'd be trying a 3310 style 750 cfm Holley with good initial pump shot, a power valve sized for the idle vacuum of the engine and a bit stiffer secondary spring to see if things would level out better.
 
Call John Cope, Cope Racing Transmissions. He carries PTC converters and had a 19 spline made for my car.
 
Thanks guys! I guess I should have titled this thread differently. What I really was looking for was a carburetor that would improve flow with minimal bog. The old Carters apparently worked OK with the pushbutton 727 behind a 426 Wedge, are they available, or what is an aftermarket alternative other than this tiny 600CFM Edelbrock? I am not going drag racing, just looking for a less choked down carb.
We've run 12.80's on a 600 Eddy carb. Move the pump rod to the hole closest to the airhorn. 7/32" float level works better as well.
Doug
 
I'm speculating a bit here, but would suspect you've more going on than just the CFM rating of the current carburetor on the engine. Generally a smaller carb would make the car more responsive off idle, but there are always exceptions. Things to consider: accelerator pump shot, secondary opening point and in the case of the Eddy you've got those wonderful step up rods and springs which work together to manage fuel flow.

Personally I've not had good luck trying to fine tune that style of carburetor, but I'm sure there are many who can do it in their sleep. Changing the secondary opening point is more involved than a Holley and the combination of jet and step up rod contour was never intuitive to me.

I've had better luck with Holley, where you can change the accelerator pump cam, the size of the pump shot, power valve, main jets and easily change secondary springs to control when they open. Usually a bog would occur when there's more air than the engine is ready for, meaning the secondary's have opened too soon. I'd be trying a 3310 style 750 cfm Holley with good initial pump shot, a power valve sized for the idle vacuum of the engine and a bit stiffer secondary spring to see if things would level out better.
You sir hit the nail on the head with your suspicion of something else going on. I bought the car last weekend from an older fellow who has several mopars and apparently just "cruised" with this one. It had some erratic missing and what seemed like a full miss in one cyl at idle. The PO may not have been mechanically inclined, mentioned his "mechanic" a couple of times. Anyway, decided to check the condition of the plugs, some which appeared real lean, others that looked like a family of rats had died in that cylinder. While I was under there, ran compression test and found all eight between 160 and 170. So far so good, looking forward to better things with clean plugs and wondering what the valves must look like...Replaced plugs and began feeding it some Seafoam to try and evict the rats and heard a vacuum whistle. Got out the tubing, stuck it in my ear and started listening around. The whistle was under the intake, near #6. Got the wrench and to my surprise found the allen bolts just a little more than finger tight. "My mechanic" indeed...
Anyway performance is much improved, although I still feel like a larger carb is in order, you were absolutly correct. Also spent some more time with the receipts from the original builder and came across one for transmission work "install 1965 input shaft..."
Thanks again for your response
Bernie
 
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