Trans Options

JimmyRich

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Hey everyone. I’m gonna have to replace the original 727 behind a 383 this winter but want to upgrade to better style. What year and such should I be searching for. It’s a 66 SF with mild 383 engine. Thanks ahead of time.
 
What type of "better" TF are you seeking? Why not contact a local transmission shop and have them do an OEM HP rebuild with a 11.75" converter or the 10.75" converter? At the worst, should be somebody in San Antonio that could do that. Contact somebody in the San Antonio Mopar Club for some recommendations.

Just some thoughts,
CBODY67
 
What type of "better" TF are you seeking? Why not contact a local transmission shop and have them do an OEM HP rebuild with a 11.75" converter or the 10.75" converter? At the worst, should be somebody in San Antonio that could do that. Contact somebody in the San Antonio Mopar Club for some recommendations.

Just some thoughts,
CBODY67
Is it worth it to update year of trans for bigger input shaft? I have the 19 spline.
 
Is it worth it to update year of trans for bigger input shaft? I have the 19 spline.

The difference is only .050" and the spline count is 24. The only advantage is you have more choices with torque convertors with the 24 spline input. The difference in strength is minimal, although in theory, the finer spline shaft might be a little stronger, but I've never seen an input shaft on a 727 break. If the input shaft did break, it's going to be because everything else broke and that's just some collateral damage.

You'd have to make some other changes to use the 24 spline input too. It would be easier to start with another transmission, but don't get into one with a lock-up convertor.

So, in other words, don't worry about it unless you are wanting a specific convertor you can't get with the 19 spline input. You haven't mentioned anything about changing the convertor...

Hey everyone. I’m gonna have to replace the original 727 behind a 383 this winter but want to upgrade to better style. What year and such should I be searching for. It’s a 66 SF with mild 383 engine. Thanks ahead of time.

The 727 you have is a pretty good transmission. If you were drag racing, had a lot more engine, ran slicks, etc., you might be concerned, but really, for a street car with a mild engine, IMHO, your best bang for the buck is to rebuild what you have and install some sort of shift kit.
 
I keep hearing the 727 is easy to rebuild. Maybe so but mistakes cost money and I can’t afford the learning curve. And patience another shortcoming. What is a estimated cost for a shop to rebuild cost?
 
One thing to consider in letting a shop do the whole deal is "flushing the trans cooler" in the bottom of the radiator. Should any "trash" be there from the old transmission, it will get re-circulated into the newly-redone transmission. Which can not be good and most shops won't warranty their work if the cooler is not flushed.

Something else to think about,
CBODY67
 
One thing to consider in letting a shop do the whole deal is "flushing the trans cooler" in the bottom of the radiator. Should any "trash" be there from the old transmission, it will get re-circulated into the newly-redone transmission. Which can not be good and most shops won't warranty their work if the cooler is not flushed.

Something else to think about,
CBODY67
I think the smart thing is to bypass factory trans cooler and go with aftermarket cooler. Any suggestions to size and type will be appreciated.
 
I think the smart thing is to bypass factory trans cooler and go with aftermarket cooler. Any suggestions to size and type will be appreciated.
That's the setup I have on my Polara with a Jegs universal aluminum radiator. It's nothing big, but it keeps the FMVB 727 cool. I'll try to get a photo tomorrow.
 
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