904 behind a 5.9 magnum engine

[CJP4130]

I'm getting ready to put a 5.9 in my 67 Barracuda and I have 2 trannies, a 904 and a 727. I just put an 8 3/4 rear in and just had the shaft cut down so I was thinking of running the 904 to avoid having it cut down again. Every trans shop I go to says the same thing, that the 904 won't live long behing the 5.9, too much torque. I explain that the one I put behing my la 360 lived forever but they say the 5.9 makes a lot more torque than the la 360. From all I've read on here lots of people running the 904 with quite a bit of motor and its doing fine. Can anyone give me some good input/advice on this subject? Thanks, Clay

 

[3406pk]

I know that a 904 can be built with HD clutches and bands that will live with over 450 hp. The stock class racers run 904 because less rotating weight and friction loss.

 

[pettybludart]

Find a new transmission shop that works on Mopars.They are obviously mis-informed about the 904,s.JMO

 

[magnumdust]

I have a 904 behind a magnum w/ heads/cam/intake/headers and nothing has exploded yet.

If you search around you'll see a lot of 10-11 second mopars using 904s. Making more power than a budget magnum swap.

 

[64Vert]

My buddy runs a 9 second Dart with nothing but 904's. :happy3:

 

[Voeltagear]

the 904 is fine. Make sure your line pressure is high enough off idle and it'll last a very long time.

 

[abodyjoe]

Every trans shop I go to says the same thing, that the 904 won't live long behind the 5.9

you have a bunch of idiots at those shops is all i can say. find a shop that actually knows what they are talking about..



my buddies 10 second demon running a 904. nothing exotic in the trans..

another friends green cuda. 11.50's car running a 904 about 1000 runs on it plus a ton of hard street miles. again nothing exotic inside of it besides a good converter.

my dart. it was a consistent 12.20 car. 5+ years of beating the hell out of it on the street and at the track running a 904 (again nothing exotic in it). trans is now in another friends car and hasn't been gone through yet.

 

[Woods74]

Do a search.