Beefing Up an A500

[TrailBeast]

• what year did they go to the 15 degree pitch?
• Also, the advantage of the A500 is the smaller housing poses less of a fitment issue in A-bodies, correct?
• And wasn't there an adaptor mount available for the crossmember so it would be a direct bolt in?
• Last, what's it take to get the speedometer cable to work with the factory speedometer??

You are correct about the A500 fitting in A bodies WAY easier than the 518.
I am using a hydraulic/electric shift control with pressure switches and had to very slightly ding the hump so the fitting coming off the governor port didn't touch. (a half inch deep x 1 inch round ding)
The cases of the 904 and A500 are the same size, but different internally and the same with the 727 and A518, and the OD unit on the A518 is bigger as well IIRC.
Yes there is a trans crossmember adapter for 904 to A500 or A518, and replacing the speedo cable with an 80" is the best way to handle that part.
The cooler lines and fittings are different as well, but the speedo gear drive and gears from a 904 fits the A500 and A518 both, but don't read correctly when put in the A500 or A518.
I needed a smaller (faster) gear to get it close.
The A series have 3/8 cooler lines as opposed to 5/16 on the non OD's, and they connect to the trans differently (pop in, instead of threaded fittings)
I used compression union/NPT fittings in the case for new 3/8 lines.

RR or Trailbeast (I believe both are transmission builders by trade)

Yea, 30 years ago.
Actually I was the Shop Forman and stick shift builder, but did domestic automatics as well, just because they were so frickin easy to do.
Mostly in the automatics I did Volvo, BMW, Mercedes, VW, Porche, Pantera and Allison.
You weren't worth having in my shop if you couldn't do three domestics a day.

Kind of glad those days are gone actually.

 

[318willrun]

You are correct about the A500 fitting in A bodies WAY easier than the 518.
I am using a hydraulic/electric shift control with pressure switches and had to very slightly ding the hump so the fitting coming off the governor port didn't touch. (a half inch deep x 1 inch round ding)
The cases of the 904 and A500 are the same size, but different internally and the same with the 727 and A518, and the OD unit on the A518 is bigger as well IIRC.
Yes there is a trans crossmember adapter for 904 to A500 or A518, and replacing the speedo cable with an 80" is the best way to handle that part.
The cooler lines and fittings are different as well, but the speedo gear drive and gears from a 904 fits the A500 and A518 both, but don't read correctly when put in the A500 or A518.
I needed a smaller (faster) gear to get it close.
The A series have 3/8 cooler lines as opposed to 5/16 on the non OD's, and they connect to the trans differently (pop in, instead of threaded fittings)
I used compression union/NPT fittings in the case for new 3/8 lines.

Good stuff, thanks!
I suppose the original A-body shift linkage/kickdown linkage could be made to work????

 

[TrailBeast]

Good stuff, thanks!
I suppose the original A-body shift linkage/kickdown linkage could be made to work????

I would think so since the A500 has two of those bosses on the drivers side that the linkage pivot attaches to just like the 904 has.
I cut all that stuff off flush on mine because of using the floor shifter and cable TP.

 

[65 Dartman]

I see a lot of great comments posted on this thread, but as the OP I haven’t seen (or maybe missed) what can actually be done by a local transmission shop to beef up the A500 internally to work behind my 2 engines - a stock rebuild 70 340 and a stock rebuild 66 273/235. Specific parts needed would be very helpful!

 

[lemondana]

There is a place called SMR Transmission in Bradford Ontario that has a lot of stuff listed on their website, valve body modification kits and so on. Check it out. Sounds like they know their stuff!

 

[TrailBeast]

I see a lot of great comments posted on this thread, but as the OP I haven’t seen (or maybe missed) what can actually be done by a local transmission shop to beef up the A500 internally to work behind my 2 engines - a stock rebuild 70 340 and a stock rebuild 66 273/235. Specific parts needed would be very helpful!

This is a basic list if you are set on making it tougher.
Hardened input shaft
5 disc billet forward drum
4 pinion steel planetary sets
16 roller rear sprag
shift kit
Kolene friction discs
Kevlar bands
4.2 (?) ratio front band strut/lever
Billet rear band piston

I may have forgotten something, but that is what you asked for.
Really don't think you need all that but...

 

[75slant6]

I believe @FredS has built some high horsepower handling A500’s

 

[C130 Chief]

Also, high stall lockup A904/A500/42RH converters are generally a custom order piece. You'll end up with a converter well matched to your combo, but it will quite possibly be half the cost of the whole setup.

 

[rumblefish360]

Are there not any non lock up A-500 or 518’s?
Can a convers be done?

 

[prican_2000]

You are correct about the A500 fitting in A bodies WAY easier than the 518.
I am using a hydraulic/electric shift control with pressure switches and had to very slightly ding the hump so the fitting coming off the governor port didn't touch. (a half inch deep x 1 inch round ding)
The cases of the 904 and A500 are the same size,

So does that mean that the same driveshaft is used as well?
So basically would this be a simple drop out the 904 and pop in the A500 and VIOLA immediate 4 spd with OD?

 

[65 Dartman]

No, I’ve got my A500 Right next to a 904 and it’s a lot longer plus the 500 uses a 727-style yoke. So, add the correct yoke to a shortened driveshaft and be good to go.

 

[65 Dartman]

You are correct about the A500 fitting in A bodies WAY easier than the 518.

I suspect this is true for the 67-76; with the smaller hump in the early A’s, I suspect some surgery will be required. Probably on the trans crossmember as well.

Yes there is a trans crossmember adapter for 904 to A500 or A518, and .

Got a link to that adapter?

 

[rumblefish360]

Us cartool.... they have a “518” adapter

 

[65 Dartman]

Us cartool.... they have a “518” adapter

Thanks! Bet it’s For the 67-76! Us early A guys probably out of luck again!

 

[rumblefish360]

According to them, yup, sorry.
I’m not up on this whole deal. Would a A-500 also fit?
67-75 A-Body 518 Crossmember Kit

 

[TrailBeast]

So does that mean that the same driveshaft is used as well?
So basically would this be a simple drop out the 904 and pop in the A500 and VIOLA immediate 4 spd with OD?

No, I’ve got my A500 Right next to a 904 and it’s a lot longer plus the 500 uses a 727-style yoke. So, add the correct yoke to a shortened driveshaft and be good to go.

Yep sorry, forgot about the driveline.
I think it was close to 4 inches that I had to shorten it.

 

[65 Dartman]

This is a basic list if you are set on making it tougher.
Hardened input shaft
5 disc billet forward drum
4 pinion steel planetary sets
16 roller rear sprag
shift kit
Kolene friction discs
Kevlar bands
4.2 (?) ratio front band strut/lever
Billet rear band piston

I may have forgotten something, but that is what you asked for.

All this looks like it stuff that might be found in a race transmission.

Really don't think you need all that but...

So do you think an "as built" A500 as found behind say a Magnum 175hp 3.9 would be fine behind a stock rebuilt 273/235. I'm guessing that possibly some, but not all of the mods you mentioned, would be needed behind a stock rebuilt 70 340. If so what would you recommend?

 

[rumblefish360]

Good question! I don’t know that answer but I might be a little nervous with the V8 having twice the HP and torque. I don’t think I’d want to participate in “spirited driving!”

 

[TrailBeast]

All this looks like it stuff that might be found in a race transmission.



So do you think an "as built" A500 as found behind say a Magnum 175hp 3.9 would be fine behind a stock rebuilt 273/235. I'm guessing that possibly some, but not all of the mods you mentioned, would be needed behind a stock rebuilt 70 340. If so what would you recommend?

Good question! I don’t know that answer but I might be a little nervous with the V8 having twice the HP and torque. I don’t think I’d want to participate in “spirited driving!”

Well, like I said earlier I have pushed mine pretty hard and even through 100 yard 1-2 shift burnouts without any bad side effects other than snapping a rear shock off.
I'm sure my Magnum has easily twice the torque and horsepower of the 3.9
I have also pushed it in OD with lockup pretty good (120 plus)on the flat and over 100 up 6% grades.
Don't even have an external cooler on it and I can tell by how it shifts that it doesn't get hot.


It's a stock A500 besides the shift kit.
It's only a transmission, so they come back out pretty easy.

 

[rumblefish360]

Well, like I said earlier I have pushed mine pretty hard and even through 100 yard 1-2 shift burnouts without any bad side effects other than snapping a rear shock off.
I'm sure my Magnum has easily twice the torque and horsepower of the 3.9
I have also pushed it in OD pretty good (120 plus)on the flat and over 100 up a 6% grade.
Don't even have an external cooler on it and I can tell by how it shifts that it doesn't get hot.

Oh! That’s good to know!

It's a stock A500 besides the shift kit.
It's only a transmission, so they come back out pretty easy.

LMAO! That’s the spirt!!!!!!

 

[65 Dartman]

It's a stock A500 besides the shift kit.
It's only a transmission, so they come back out pretty easy.

I bought a pair of 500's from a member over at slant6.org; one was rebuilt, came with a mild performance 2300 stall converter and used behind a pretty stout slant with an A100 adapter. It was pulled for a Th200. I plan on using this one behind the 273 in my 65 Dart wagon. The other A500 was used behind the same slant in the same vehicle but was pulled for the 2nd A500. I plan on getting this one rebuilt to use behind the 340 in the 47. Are there any upgraded valve bodies beside stock available for these transmissions?

 

[TrailBeast]

I bought a pair of 500's from a member over at slant6.org; one was rebuilt, came with a mild performance 2300 stall converter and used behind a pretty stout slant with an A100 adapter. It was pulled for a Th200. I plan on using this one behind the 273 in my 65 Dart wagon. The other A500 was used behind the same slant in the same vehicle but was pulled for the 2nd A500. I plan on getting this one rebuilt to use behind the 340 in the 47. Are there any upgraded valve bodies beside stock available for these transmissions?

From what I have seen the 2300 stall works really nice for these transmissions in cars, and there are apparently some different valve bodies, but I'm not up on what they are.
Sorry.

 

[65 Dartman]

OK many thanks for all your help. Now to find a transmission builder that know these transmissions and find a converter builder who knows them as well!

 

[rumblefish360]

From what I have seen the 2300 stall works really nice for these transmissions in cars, and there are apparently some different valve bodies, but I'm not up on what they are.
Sorry.

So to recap, the 500 comes in both LU and non LU?
Can it also use that kit (518 kit) above to mount in the car as well?

 

[TrailBeast]

So to recap, the 500 comes in both LU and non LU?
Can it also use that kit (518 kit) above to mount in the car as well?

Up through 1991 there were non lockup versions of both the A500 and the A518, and a guy could run a non lockup converter in either one also, and just have 123 and OD.
The cross member can be used for either as the mount pad is in the same location even though the 518 is longer.