Will a 904 work with a 360 motor?

[69barracuda]

I am thinking of swapping the 318 in my 69 Barracuda with a 1974 360 that I have. I know the 360 is externally balanced and the 318 isn't. Does this make a difference to the torque converter or will it even bolt up? Is there a way to make this swap work without using a 727 and cutting the drive shaft?
Thanks for any help you can give.

[vanderkwv]

The 904 will work but balanced torque converter to make it work. I'm doing the same thing I've got a 318 that's being replace by a 360.

[dwc43]

You can use the A904 with the 360 with the proper weighted converter or the proper flex plate and a non weighted converter. I would not use it though. IT's pretty weak. Killed a bunch of those behind stock 318's. I'd put an A727 in it. THEy are almost bullet proof and it's the last tranny you will put in them.

[vanderkwv]

Come on , you're telling me you can't build a stout 904 to last behind a 360?

They're tougher than that aren't they?

[dwc43]

Not unless you put some major money behind them. Like I said, I've torn up more than one behind stock or mild mod 318's. Not my favorite and it's not worth it when you can build an A727 for the same money and never have to worry about it.

[it's all dodge]

if you don't race it, I would use the 904, you dont have much to loose, but what it cost for a flexplate and the time of bolting it up, there are people racing them, of course most of them are using trannies built to race, or alot less miles too. Depends on how much you have to spend, some people on here act like mony is never an issue, just loaded with money!

[John Kunkel]

An alternative to both the standard 904 and 727 would be the 999 which is a heavier duty version of the 904 built specifically for the 360.

[pcrmike]

Exactly right, John, and also used behind 318's in trucks for several years. :-)PCRMike

[70AARCuda]

Been bracket racing with a 904 with a Transbrake for 10 yrs or so...i rebuilt earlier this year due to ring gear breaking and taking out sprag.

Car runs in the high 10s in Vegas...

have 5 clutches in front clutch pac...and replaced the large spring with the 24 spring kit in clutch pac....otherwise no special parts..

engine is a 360....

[LA360Dart]

Hi All;

If you have to start from scratch 904/999. Only if you have a 727 build one. The A999 has lower first and second (D33) is transcode on build plate.
Do not beleive nay sayers 904/999 are strong enough for most HP street/strip applications. Once you start going very fast in the low 10's you would need high dollar stuff on internals to keep trans alive.

Just my opinion
Denny

[909duster]

La360dart,

Remember the overkilled blue demon 474 ci small block runnings 9's and a 904 trans and drove from San Bernardino county to Spring Fling some 75+ miles.
I believe it plenty stong unless its used in roundy round when your two laps down after the first three laps and your X headed 360 just puked.

Just a thought.

[dwc43]

Originally Posted by 909duster

La360dart,

Remember the overkilled blue demon 474 ci small block runnings 9's and a 904 trans and drove from San Bernardino county to Spring Fling some 75+ miles.
I believe it plenty stong unless its used in roundy round when your two laps down after the first three laps and your X headed 360 just puked.

Just a thought.

Circle track racers do not use autos in 99% of all cases. I even tried the A727 in one of ours. THey just wont come off the corners like a 3spd will. Never seen anyone 2 laps down running an X headed 360 either, but I have seen a bunch of them win with one. And your guys A904 cost him twice as much and must be rebuilt more often than a good A727.

[rumblefish360]

uNbelIeveablE!

OK, Ran a stock 904 with deep pan and extra cooler for 9 years behind a wramed up 360 in a heavy Dodge Magnum that could outrun stock and mild upgraded stangs.
(pretty good for a low comp. engine)

[TK]

Yup, I agree, as long as it ain't a truck, 904's just fine.

[kamstra]

The 904 uses a different Yoke than the 727. The driveshaft will also be a different length.

[5thAve]

Since you already have a 904 just use it until the 360 kills it and then get a 727.

[BJSracing]

I used a 904 behind a Not exactly stock 360 and footbraked the car. Leaving in second gear it ran a 13.94 @ 104. Now I don't know about you but that isn't too bad. I also drove this car all day every day while I was in the military. It was more dependable then the 94 Grand Am we had at the time. Oh yeah BTW I had the converter out of the /6 tranny that was originally in the car with that combo. I just drained it, filled it and drained it again. Shoved it in and down the road I went. DW don't say it can't be done. I did it with stock parts and it did better than ok. To the best of my knowledge it is still in the car and that was 6 years ago. You don't know everything.

[a440plus6®]

They are the ONLY tranny I use behind my small blocks.....340s and 360s.
Lighter rotating mass=faster windup, not to mention weight of trans diff and gearing. Been using them for years.

[dodger1]

I agree, the 999 behind my mild 360 works just fine. Came out of a 318 Cordoba with a zillion miles on it, and got rebuilt to cop-car specs by a local trans shop who did lots of tranny work for the R.C.M.P. The 2.74 first gear is more useful with the 2.94 axle ratio I run.

[perfmachst]

hello, the 904/999 is the trans of choice in stock and super stock racing.
it will live qiute well behind a 340. 360, 383, 426 hemi, 440 motors.
granted they are built stout, but they do hold up. they are .2 tenths faster over the 727, install the aluminum hubs, etc, it's another .2 tenths faster yet.
just food for thought.

[84ram]

If it's (re)built properly, with high quality parts it will hold up well. I wouldn't expect it to last if it has NOT been gone through and you put it behind much more than a stock 360 though.

My '72 Swinger started out with the stock a904 trans and convertor in it, and about a month after we dropped in the built 10.5:1 328ci small block, once the break-in was done, we found that the weakest link was the stock rearend when it tore the 2.76:1 gears out of the housing romping on it from a standstill. (those old slapper bars worked pretty well!)

After replacing the rear with an 8.75 with a 3.91:1 ratio, we found the next weakest link when it smoked the stock a904 trans. We could have re-built the a904, and it would have worked well, but we already had a built a727 with a new 3500 stall convertor and we chose to swap that in instead. Never had any more transmission issues for as long as I had that car,(several years) and I ran the snot out of it nearly every time I drove it. I sure do miss that old heap .......I had more fun with that thing than any other car I've ever owned.

[cageman]

Geez, nobody uses autos in circle track, that is news to me, as it is really all I have ever used, the 904 is a good trans.
Just buy a b&m flexplate for a non balance convertor and run it.
Whats all done to the 360?

[John Kunkel]

Originally Posted by cageman

Geez, nobody uses autos in circle track, that is news to me,

Just more drivel from the Minister of Misinformation, I've built lots of 727's for roundy-pounders. They usually only use 2nd gear on short tracks so I build them accordingly.

[Jim13]

I did what you are saying last year. 318 came out 360 went in. I rebuilt the 904 and added a manual valve body when I did the swap. The car runs in the high 13's and I have about 60 passes on it so far with no problems.

[FASTDARTCHESTER]

It don't take a whole lot of money to make a 904 work; it takes thought. I built a killer 904 for my Dart in '02. The only custom things were a Kevlar lined band to my specs and a turned front clutch drum OD. Believe me, the 904 can be made to work great on a budget, you just have to have the WILL to do it. My Dart is 12.10's@112.

The stock 4-plate front clutch can accept 5 with the Raybestos blues from Mancini for more surface grip. Not all clutch/friction discs are created equal (I really have had good luck with Raybestos). I did this, used a Turbo Action Cheetah manual valve body, and many other goodies with good luck. Just common sense stuff.

All said and done, I think I had around $750 into it.

Good luck!

[Mopartranman]

I'm new here and don't mean to but in, But a 904 will live a long time behind a 360. And dont take a fortune to build them. I have guys running them that are running in the 9's without any trouble at all. Just pulled one apart that's in a 68 dart bracket car i built 3 years ago for a friend. It run's low 11's. Been in the car for 3 years, Pulled it apart and clutch's and bands still looked like brand new. I replaced a pump bushing, front and rear seals, and pan gasket and put it back together. I only run 904's behind small blocks

[Tarrbabe]

It isn't as strong as the 727. Even the full race 727's use the smaller 904 TYPE parts as they are lighter and produce quicker ET's. But even then, they must be rebuilt more often. The 727 has a rep for being super strong as it came with a Hemi! But spin the tires and let them catch all at once!!!!!!!!!! Anyone that doubts this, try it. You will break the overrunning clutch fast. Same with the 904. The 904 will work but you should be sure it is in good shape before you put it in as it won't last as long as a 727 but will hold up very well depending on treatment. Harsh treatment breaks parts. Abuse breaks them quick. How long will it last? How long will a marrage last? Depends on many things I guess. Build it as strong as you can and go for it. Speed cost money, how fast do you want to go? Many super stock darts and dusters have set records with the small trans.
Make sure the balance is right and have fun.

Just thinking out loud.