20+ years of "Building 904/727 for drag racing use"

Rat Bastid said

I‘ve seen them explode. Aftermarket cases aren’t made because someone wanted to open a new market.

Lets not turn this into the thread equivalent of aftermarket blocks.

If you want to run a TF with big power and a stock case, by all means have at it.

I run clutches so what the converter crowd does has little bearing on what I care about.

Defending a transmission because of brand is the same as saying you can stay with the 8.75 axle even though the 9 inch is far stronger.

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I wouldn’t say anyone is defending a transmission purely because of brand. But the 727 will handle a lot of power and as Duster346 has just gave conservative numbers of 1500hp for the 727 and 1000hp for the 904 cases. I’d consider 1000-1500hp a lot of power. So to say the 727 won’t handle power is false.

My example, my personally owned 727 came which out of a top sportsman car that ran 4.70s on nitrous, 2700lbs 1970 GTX tube chassis. The 727 was built by Rick Allison in 2006. I bought the 727 used off of a friend who bought the GTX and decided to change its setup. I put the 727 in my car which runs 5.50s-5.60s. Never tore it down before putting it in. Ran the trans 500 runs before I had converter fins start to fail and put metal through the trans. I tore it apart, for precautionary measures, and found nothing was harmed inside. The clutches and steels looked great, could still read the writing on them and I have no clue how long they were in there before I took it apart. I freshened the trans and back in the car it goes. Worked just as good as when I took it out. Not that I am laying down an overwhelming amount of power, but for running what my car runs, my 727 works well for me.


Trust me, I see your point about the TH400 having an advantage of the aftermarket case but for a Mopar naturally aspirated racer (which I believe most of us are) who wants to simply run 9s with an A body small block, the 727 or 904 will work just fine.