A904 upgrade

[eastvan52]

restoring a 75 dart swinger - has 3 speed a904 - what upgrades is there - can i go to the A500 this tranny has the overdrive

 

[67Dart273]

Not without chopping up the floor, and reconstructing the crossmember

Do a search A few of the guys have gone to a GM 200 trans

 

[txstang84]

restoring a 75 dart swinger - has 3 speed a904 - what upgrades is there - can i go to the A500 this tranny has the overdrive

Apart from what Del mentioned, upgrading a 904, you can go to a manual valve body, or just install a shift improver kit...you can swap the clutch pack and other guts from a A998/A999 (lower first gear, and more clutches I think)...as Del said, run a search...you'll find ALL sorts of stuff...

 

[Woods74]

LOL, you don't have to search far dude, look at the top stickies! :blob:

 

[transman]

restoring a 75 dart swinger - has 3 speed a904 - what upgrades is there - can i go to the A500 this tranny has the overdrive

What is the end use of the vehicle? Daily driver, race car? How much you going to drive it?
What engine, how much HP?
As others have said, 904 will do just fine, and unless you're stuffin a big cubic inch engine in it, and doing a ton of driving, the process of putting in either a TH2004R or the A500 may not be worth all the expense and trouble for what you'll save in fuel costs.
I drive my car about 1000 miles per year in good weather. Fuel costs run about $150-200 per year. Now if I was putting on a lot more miles then I'd perhaps look at an overdrive of some type, probably a 4L60E.

 

[eastvan52]

the 225 slant 6 will be rebuilt but not for performance - so a mention of a manual a904 - do you mean a 3 speed shifter on the floor ? -

 

[pishta]

manual A904 is a manual shift auto, ie no automatic functions (upshift,downshift, etc) its just a reprogram kit, transgo, B&M, Fairbanks. shift improver raises line pressure and provides much faster shifts. Most of these kits (ie. Transgo) comes with 3 stages in one kit. street performance/strip/full manual. For instance, the full manual stage comes with a dowel in place of a spring in one of the accumulators IIRC but I might be thinking of a C4.
Your tunnel down by the driveshaft is only about 5" wide with the trans being about 3" the A500 is massive back there because of the overdrive gear, needing a new tunnel and trans mount. TH2004R or AOD is more like a 904 in dimensions.

 

[TrailBeast]

I think the 4L60 or the AOD either one would be pretty big in there.

 

[Rodzilla]

For a stock slant six I would just do a factory rebuild on trans, performance parts would be a waste of $$$$ in that 904. Get an ATSG manual and watch a bunch of you-tube vids and give it a whirl. I just finished my first 904 build, was pretty straight forward.

 

[transman]

For a stock slant six I would just do a factory rebuild on trans, performance parts would be a waste of $$$$ in that 904. Get an ATSG manual and watch a bunch of you-tube vids and give it a whirl. I just finished my first 904 build, was pretty straight forward.

X2 on what he says. 904 properly rebuilt will last a jillion miles behind \6. At one time, most cabs in Vancouver city had the leaning tower of power in them with a 904 transmission to get them around the area. Bodies wore out before the engine or transmission did.

 

[eastvan52]

everyything that is done properly will do what it is intended to do - i am just doing that at this moment to figuring things out - the slant 6 will be beefed up to gain some extra hp to run balanced and efficiently - nothing crazy here except for myself lol - thanks