what are the pros and cons of a rollerized 727 and are they better than the 904 at scrubing off ET's? this for my street/strip car with 408.

A while back i ran a pretty much stock 727 with just a reverse manual valve body and good bands and clutches.It was the numbers tranny for my old 70 340 Duster.Car ran 10.70's at that time.416, Eddies, etc.

I took it out to use as a spare, and had a trick 727 built. Aluminum drum, full roller, yada, yada. Never saw ANYTHING et wise with the swap.Not even a hundredth as far as i could tell. If there WAS any difference, it was miniscule.

I suspect a 904 is going to be 1 to 2 tenths better than ANY 727 you build, based on guys i know who have swapped from 727 to 904, and many posts i have read on here regarding this topic.

Chrysler did a lot of testing back in the mid-'70s between a 727 and 904 in Stock and/or Super Stock small block combos. With both versions built to the same degree with matching converters, the 904 was an average of .15 faster than a 727.

I footbrake a JW Trans. 904 with good bands and clutches, a reverse manual valve body, 4.2 lever and 2.71 low gear. No aftermarket billet or aluminum stuff or roller bearings. Works great, no problems and excellent wear characteristics with Amsoil Supershift fluid. Best of 1.47 60' with 11.31 @ 115 time weighing 3,540+. Built right, they are a very durable trans and you'd have to spend a LOT to just try and get an extra .15 out of a 727.

You probably don't need a 2.71 low gear and, in theory, a high torque engine will see less difference between a 727 and 904. But a 727 should last longer and be more durable.

thanks guys. i talked with john cope about this also. i'v decided to keep the 727 just the way it is. 904 would be the best move to shave ET,but it would be a big exspense to gain .10-.15.

There's a easier and cheaper way to pick up a .10 or .15.

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There's a easier and cheaper way to pick up a .10 or .15.

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do tell....

what i'm thinking of doing to cut .10-.15 from my ET is rebuild the 408 with a fresh bore and flat tops,mill the indys .030" add new rings and bearings. should be affordable and take my compression from 10.6 to 13:1. i'll be adding cal-tracs and mono springs in a couple months. getting rid of the ss springs should shed some considerable weight.