Lets talk trannys

Discussion of the 331-354-392 HEMIs.

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Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Lets talk trannys

Post by Hemi8me »

I have been thinking about a tranny choice for the 354. I have been thinking 700r4. The over drive is a nice option.

What can you guys tell me?
What years were they not computer controlled?
What power can they handle stock?
Is there better years to choose?
Truck or car tranny?
Is there a better tranny than the 700r4?
The hemi is all I have for my Rat Rod.....1956 354 HEMI
NE57
Posts: 192
Joined: Fri Mar 27, 2009 12:54 pm

Re: Lets talk trannys

Post by NE57 »

How much extra work is involved with the 700r4? Will it fit your chassis without being more trouble than its worth? If you go overdrive it might be good to pick your cam so it runs nice at cruising rpms, which means you need to plan your gearing and tire size.
Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Re: Lets talk trannys

Post by Hemi8me »

NE57 wrote:How much extra work is involved with the 700r4? Will it fit your chassis without being more trouble than its worth? If you go overdrive it might be good to pick your cam so it runs nice at cruising rpms, which means you need to plan your gearing and tire size.
Now I'm hosed, I never thought that far into this. Extra work????? Every tranny needs an adapter. What kind of extra work are you talking here?

I am going to talk with Hot Heads about cam and pistons. Looks like I better let them know about the tranny. Never thought the two had to go hand and hand.

Tire size and gearing........The damn engine is going in an engine stand. :lol: I think it will fit that chassis. :D It will go into a rat rod, so fit is not a problem.
The hemi is all I have for my Rat Rod.....1956 354 HEMI
George
Posts: 694
Joined: Wed Aug 25, 2004 4:12 pm
Location: Fl

Re: Lets talk trannys

Post by George »

The OD only helps out on the highway. In town there isn't any real diffrence vs non OD.If you only driving in town & some street racing, no point in it. If you plan on a lot of Interstate runs to car shows, Power Tour, ect there's big advantage. How important is MPG vs off the stop light performance? If you like ripping starts that 3.75-4.11 gears give you, the OD will be a big help on the road, but you'll still get crap milage in town. If you want a rod that looks like it'll pass everything but a gas station but actually gets decent to good MPG, you can run from 3.08-3.25s or in between the 2 groups.
NE57
Posts: 192
Joined: Fri Mar 27, 2009 12:54 pm

Re: Lets talk trannys

Post by NE57 »

For example my car is a 66Dart and I'm using a smallblock 727, mostly because I figure it'll fit with less hassle since darts had torqueflites as an option. In some cases all that's needed is a hafty hammer to roll back the tunnel lip. I've read the OD trans is longer so the rear mounts would have to be reworked. Add in that MAYBE I'll have to set the motor back some to clear tie rod and steering box...don't know til I try to stuff er in. If I have to setback that means firewall and tunnel mods which I don't really want to do but will if I have to. There's going to be chassis work needed too, subframe connectors at the very least, disc brake swap, master cylinder relocate, driveshaft, 8 3/4 swap, etc etc etc. So the list of work gets long and if choice of a trans makes it a little bit simpler and gets the car on the road sooner, I'm all for that. My motor came with a chevy trans adapter and once I started thinking about how things have to fit together I opted for the safer route and traded for a TF adapter.

If you're doing a frame off on an old roadster or something, sure it'll be easier to fab whatever you need to mount the motor/trans but you still might have to modify the floor, who knows? Maybe you could search whatever your ideal car is and see what people have done.

About the cam/axle/tires. Say you picked a somewaht radical cam that started building torque at maybe 2800rpm. In OD you might be turning, oh I dunno maybe 1800rpm when cruising. You might be chugging to get up long grades or down shifting. A cam that starts building torque at 1500 might be a better choice. Tires, gear, OD% all work together to put the engine in whatever rpms at whatever mph. You can tune all those for acceleration or for driveability. Pick a cam that's got decent torque at whatever rpm the OD/gear/tire size combo dictates when cruising.

I'm no expert but I hope something there is useful.
Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Re: Lets talk trannys

Post by Hemi8me »

George wrote:The OD only helps out on the highway. In town there isn't any real diffrence vs non OD.If you only driving in town & some street racing, no point in it. If you plan on a lot of Interstate runs to car shows, Power Tour, ect there's big advantage. How important is MPG vs off the stop light performance? If you like ripping starts that 3.75-4.11 gears give you, the OD will be a big help on the road, but you'll still get crap milage in town. If you want a rod that looks like it'll pass everything but a gas station but actually gets decent to good MPG, you can run from 3.08-3.25s or in between the 2 groups.
George,
Since I plan to do some longer trips, the OD would be nice. Says a little on gas. Not sure on the rear end gear at this time. Kinda thinking 3.55 or there abouts.


NE57
Car will be a 28 to 32 5 window or tudor sedan so the tunnel and other stuff won't be a problem. I will remember what you are talking about when I call Hot Heads.

Thanks for the info guys. Anymore would be great.
The hemi is all I have for my Rat Rod.....1956 354 HEMI
Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Re: Lets talk trannys

Post by Hemi8me »

How about other trannys? Any better than others?
The hemi is all I have for my Rat Rod.....1956 354 HEMI
speedicusmaximus
Posts: 143
Joined: Thu May 18, 2006 11:31 am
Location: UK

Re: Lets talk trannys

Post by speedicusmaximus »

There were adapters to fit the A904 based OD unit, the A500 (?). I think T. R. Waters was one supplier of them.

Not sure about the physical dimensions though,. It might be quite bulky compared to the original 904, as the OD part was an add-on to the original design.

Do Bouchillon Performance do these adapters ?

If there's any real HP coming out of your Hemi, then I suggest you upgrade to the A999 internals. Most good autotrans rebuilders should be able to guide you on this.

Mike
Beep ! Beep !
Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Re: Lets talk trannys

Post by Hemi8me »

planned HP is 375 to 400.
The hemi is all I have for my Rat Rod.....1956 354 HEMI
budmspeeco
Posts: 133
Joined: Tue Dec 21, 2004 5:35 pm
Location: South Houston, Texas

Re: Lets talk trannys

Post by budmspeeco »

Another advantage is the LOW first gear ratio of 3.06 whereas a 350 turbo is only 2.52. It helps with the launches for street racing. I put a 700R4 behind a worn out 350 small block a few years ago. The rear gears were 3.55s and the tires about 28-29 inches tall. It turned almost 3000 at cruising speed. With the OD it dropped to a much nicer 2,100 or so. Since hemis don't need a lot of rpm's you could put some 3.50s to 4.00s ans still be safe. Reduction is in the .700 range. I had the trans built by a local trans shop here in Houston, All Trans on Telephone Road, phone # 713-643-6234. Ask for Mike!! No core needed, with a converter and the stall of your choice ( he builds his own converters), it's in the neighborhood of only $1,500.00. It has NO electrics, just the throttle cable to the carb. It is critical for it to be adjusted properly. I have bought several and know of others that have used them. I was told by one guy that had torn up three in a row from someone else that Mike's setup was the best he had ever seen or used. Mike is a real car guy as well as a great trans man. He even sponsors a driver on the WOO circuit. If you want a solid trans and/or just some solid advice, give him a call. Buddy
'48 anglia
speedicusmaximus
Posts: 143
Joined: Thu May 18, 2006 11:31 am
Location: UK

Re: Lets talk trannys

Post by speedicusmaximus »

Had a chance to do some research, and came up with the following information on early Hemi engines to later Mopar (and other marques in some cases) transmissions:

SMR Transmissions - scroll down the page for the info on A904 and A727 three speed and o/d versions from them. They also have upgrades for the A904 TorqueFlite - see contents column:

http://smrtrans.tripod.com/smrtransmiss ... o/id9.html

T. R. Waters:

http://home.together.net/~twaters/index.html

Willcap Trans adapters - read carefully as they have plenty of options:

http://www.wilcap.com/Hemi.html

And there's Hot Heads' offerings:

http://www.hothemiheads.com/transmissio ... index.html

Hope this all helps !

Mike
Beep ! Beep !
George
Posts: 694
Joined: Wed Aug 25, 2004 4:12 pm
Location: Fl

Re: Lets talk trannys

Post by George »

speedicusmaximus wrote:Had a chance to do some research, and came up with the following information on early Hemi engines to later Mopar (and other marques in some cases) transmissions:

SMR Transmissions - scroll down the page for the info on A904 and A727 three speed and o/d versions from them. They also have upgrades for the A904 TorqueFlite - see contents column:

http://smrtrans.tripod.com/smrtransmiss ... o/id9.html

T. R. Waters:

http://home.together.net/~twaters/index.html

Willcap Trans adapters - read carefully as they have plenty of options:

http://www.wilcap.com/Hemi.html

And there's Hot Heads' offerings:

http://www.hothemiheads.com/transmissio ... index.html

Hope this all helps !

Mike
There's also Quality Engeneered Components for Mopar adaptors. There's a starter clearance problem when using a 904(or based) tranny.
Hemi8me
Posts: 74
Joined: Wed Sep 01, 2010 8:14 pm
Location: Akron, Ohio

Re: Lets talk trannys

Post by Hemi8me »

Which would be the strongest stock OD tranny? What cars or trucks did it come in?

Is there a difference between truck trannies and cars trannies?
The hemi is all I have for my Rat Rod.....1956 354 HEMI
speedicusmaximus
Posts: 143
Joined: Thu May 18, 2006 11:31 am
Location: UK

Re: Lets talk trannys

Post by speedicusmaximus »

From a stock point of view, the A518 is the stronger unit. But, people such as SMR Transmissions have gone to an awlful lot of trouble to negate any weaknesses in the original design of either transmission. Your best bet is to talk with them. Remember that the A904 based o/d is physically smaller, so if you have space issues, then it could be the ticket. But if it's just longevity, the go with the A518. SMR Trans have run their products on the quarter behind engines putting out a lot more HP than your planned Hemi.

Note: There's others out there with products equally respected as SMR. I mention them cos they're the one's I know of !

Good luck !

Mike
Beep ! Beep !
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