Hey guys I am in the process of a cummins swap into my 76 chevy and I decided to get rid of the getrag and go with a 727 it is freshly rebuilt stock. And stock TC. My concern is that the stock stall on the TC won't be right with 3.54 ratio and 37 inch tires. I know very little about auto trannys so all help is very appreciated.

 

You should be okay, especially with that tall of tire on the 3.54 gears.
You may WANT a bit more converter slip with that combo, to limit breakage.

The biggest rule on an auto is KEEP IT COOL, ergo a BHA cooler is recommended.

What's going to happen to the poor Getrag?

Mark.

 

How hot is too hot? I ordered a temp guage but I'm not sure where it should run temp wise. What exactly does more slip translate to? A different TC? I traded a guy straight across my 2wd rag for his 4wd 727 so it's going to a good home I wouldn't just throw it away it was a very good tranny it's just that my old lady can't drive a manual and after many failed attempts to teach her I broke in and decided while I was doing the swap I would put an auto in it.

 

At least the rag got a new home to be useful in.

I'm not sure on transmission temps, seems like "hot" is around 400 degrees, but CMIIW.
More slip does generate more heat, but CAN limit any potential damage.
It's exactly what Dodge did to attempt to help the overdrive (518) in our 1st gen trucks to live a bit longer to make warranty.
When Dodge introduced the 518, they also made the over-the counter under-bed cooler available, in attempts to combat the extra heat.

Mark.

 

So does higher stall mean higher slip? Or lower stall? Also what are some good coolers? I have looked at a few I don't really want to go with an auxiliary with a fan just yet I would rather start with a small better than stock type that goes up front if I need to I will add one later in time. I had a stock dodge cooler mounted up front but I accidentally ran into it with the fork lift and trashed it. Luckily that's all I hit.

 

A higher stall means more converter slip plus more heat!! I run a th400 in my cummins swap with a deep pan with oil cooler tubes and a big aux cooler. I have the converter as tight as it will go!! never been over 190 degree!!

 

Does anyone know the stock stall?

 

I believe stock stall is around 1400-1600, too hot is 200* in the pan.
a low stall converter is 1100.

 

So I guess all I need to know now is what brand of TC do you guys recommend and what stall for my application do you guys recommend?

 

Call SunCoast, Goerend or Specrite. Tell them your trucks specs and what you world like it to do and they will give you a recommendation.