Have a buddy with a 72 challenger with a good running stroked 340 making about 500 hp, 391 gears and a slipping 904 trans. He was thinking about rebuilding his current trans but has decided to buy one already done. His current setup is a reverse valve body with 3000 stall converter. He is looking at a complete ready to go trans from ATI Transmissions for about $1,500 and wondering if anyone has any feedback on there units or recommendations for one of the other trans guys out there. He is not easy on his car and would like to see him get one that works well. Car will be mainly local street and highway used, but he is not easy on it, banging gears is the norm. Where should he buy his new transmission?

Darren Smith with Pro Trans in Lancaster CA.

http://www.protransracing.com/

They are one of the premier Mopar and otherwise race trans builders and manufactures out there.

They manufacture on site many of the trick Mopar trans parts. Sometime repackaged and sold through other sources.

They can definitely build a 904 to handle that application. Just need to talk with them on how cost effective vs the benefits is that going to be vs a 727.

Steve, thanks for the information. He likes the 904 because of the low 1st gear and weight reduction. Does a 904 really make a noticeable difference from a 727 for street/strip use?

The 904 does free up some horse power due to the internals and it's lighter weight help this trans to a favorite. Clearly at this point a talk with the builder on what exactly he has and how he drives it needs to be discussed so all issues are hammered out and understood.

I gave him the link for Pro Trans as well as a few others, and told him to ask questions and see who he feels comfortable with. Most any one of the big trans shop should be able to put together a nice piece for him. The key is one getting put together with care,testing it and making sure it works as advertised.

A while back one of the Mopar magazines did a favorable write-up on SMR Transmissions. The write-up centered around SMR's work with 904's and the ability to make them take serious hp.

Link.

By just looking at the website info provide by the main trans builders out there, SMR seems to be the most detailed about what they will do to the transmission.

I have a small shop in Kentucky called Performance Torqueflites. We have done several 904's of various performance levels from stock to some well into the 9 sec range. We have cores in stock and can ship. 502-500-7163.

My Craigslist Ad!!!

Also contact John Cope at CRT....A Moparts sponsor and advertiser...
https://www.coperacingtrans.com/index.php?osCsid=f0edc58517934ea7f44d62e8a312273b

I used to street race in the Detroit area late 70's thru mid 90's. Way big difference in the 904 than the 727. Cost more but way more bang for the buck. The best guy in doing the 904 is Joel's on Joy in South Lyon,Mich. I picked up a second faster by going to his 904 than his 727. He builds the best of both. That is why all the super stock SS/AA guys use his trans. Way more torque and less H.P. loss with the 904. There was a major difference in the way my car left the line and launched harder with the 904. With a small block to this day I use his 904.

Call john Cope at crt.

you will not regret it

Thanks for all of the replies fellas. He has spoken to Dave at Pro Trans and he likes what the man has to say. They discussed what he does with the car and some of the components that can be used in a 904 application. He was familiar with the company that he bought his converter from Continental who are also in So Cal. Dave basically got all of the information that he needed from my buddy and told him he would get back to him with a setup and cost that will cover all of his needs. My friend said he was very confident that Pro Trans knows what they are doing and will supply him with his next transmission. Many of the other guys mentioned are competent as well, but dealing with a guy who is in the same state has its benefits and saves a bit on shipping. Plus doing some reading on guys who use this shop for there trans needs shows they know there stuff!

904 is about 35 lbs lighter then a 727 which is mostly internal. A 904 is at most about 2 tenths faster then a 727 with converter being equal..

I picked up .15 and about 2 mph back in 1993 went i changed...and never looked back.

all 3 cars in signature below are 904s,,,they are so easy to build that even I can do it...

there was a magazine article many years ago that listed the hp required for each trans...

powerglide was about 18

904 was 24 ...same as ford c4

727 was 45 hp...about the same for T400

and the Ford C6 was the worst...

maybe some has the chart saved somewhere

I guess my experience and advise would be the opposite of what I read here. I have bracket raced my Dart for about 25 years now. After 2 904's tearing up within a 3 year time period, I decided to go with a 727. That has been over 20 years ago now, and no more transmission problems. I race eighth mile, and the 727 ran .003 slower. I gladly traded the .003 difference for the reliabality of the 727!