Hot Rods B&M Hydro transmission help to identify

I have 2 for my 392 Hemi and I want to keep the most heavy duty racing one. Problem is that I don't know what the serial numbers mean.

Any help greatly appreciated. Somehow the H.A.M.B dudes always know the answers, blow my mind every time.

 

Only one B&M, other is Hydro-Motive. S/N’s don’t tell much, if anything. Need original Or factory paperwork to determine usage. Good luck with that. A genuine B&M will not have rivet holes where the nameplate is located.

 

Is there any info on Hydro motives anywhere?

 

So, the Hydro-Motive is more complete. The B&M doesn't have the flywheel and crankshaft adapter. Hard to tell from the picture but if it says P55 UC on the left it's a 55 Pontiac core and UC means unblown competition. Don Stanley of TSI transmission in Addison, Illinois passed a few years ago. Don was from Hydro-Motive. TSI came after Hydro-Motive ended. After Don passed everything from the shop was sold off as the business was closed down and it seems any history or records was lost.

 

I think it says P55 HO

 

Take a closer look. BC is Blown competition, UC is unblown. Sometimes the stamps get a little mangled. B&M used a couple different style tags but those are the codes. There may be another code but I can't remember for sure it's been a while.

 

As others have mentioned, the first one is a Hydro-Motive. Not B&M, but their own separate company. Word is that they made very strong hydro transmissions back in the day.

The second one is a B&M. I think that's mid-late 60's or early 70's after they changed their tag design. The case used was a 1955 Pontiac transmission case. The S/S stands for Street/Strip. It was a more moderate build suited to guys who needed a transmission with street manners but could also make weekend passes.

 

The stamping to the left of the logo was the core transmission information. The stamping to the right of the logo tells the build style. In this case S/S (Street/Strip) and then the B&M serial number.

 

Lots of useful info on the Hydro Tech group: https://www.jalopyjournal.com/forum/social-forums/hydro-tech.671/

You'll have to join the group to see all the threads and information.

 

Yup, SS =Street/Strip that's the other code I couldn't remember. I couldn't really make out the digits on my phone picture and I haven't looked at mine in a long while. I forgot the code was on the right side. Thanks Speedy

 

Speedy to the rescue.

Which transmission would be best for drag racing. Was hydro motive early B&M?

 

I wonder how hard it is to find a flywheel and crankshaft adapter for the B&M.

Does anyone have a picture of flywheel and crankshaft adapter, or is B&M same as Hydro-motive.

 

B&M was building 4 spd. Hydros before Hydro-Motive. H-M was Chicago based and had an excellent reputation.

 

Use whatever parts you need for the Hydro-Motive unit from the B & M (probably only the starter motor adapter). Judging by how rusty the B & M is, the insides are probably not much better, and it has a busted bellhousing to boot, although that could be swapped if you're set on using the B & M. The only advantage the B & M "might" have, would be the patented valve used in order to keep the trans in first gear manually (if it even has it being a S/S trans); you could also swap that over to the Hydro-Motive after cleaning it up. The B & M has a shorter extension housing and output shaft than the Hydro-Motive trans, and I'd prefer to use that length myself, but you're probably going to have to build a driveshaft anyway, so it's really a moot point. Personally, I'd use the starter motor adapter off the B & M on the Hydro-Motive trans, and be done with it. The B & M just looks like it sat in a wet environment for way too long. You'll be miles ahead with the Hydro-Motive trans, and there's really NO difference in one being stronger/better than the other, besides B & M being a better known name. The B & M should be a slant pan trans, with only a single band that can be adjusted externally; is the Hydro-Motive trans also a slant pan, or is it a flat pan? A flat pan will have adjustments for both band externally, and be slightly more preferred. Those are my "opinions".
I am Butch/56sedandelivery.

 

Nope. Hydro-Motive was a big competitor to B&M on the east coast. They were based out of Chicago.
I've been told that they bought out B&M's surplus parts back in the day after B&M moved on from building Hydro-Sticks.

It's hard to say which would be the better transmission without knowing the guts and details of both of them. My gut suggest the Hydro-Motive as the B&M is a lighter duty Street/Strip version as opposed to the all out Blown Competition or Unblown Competition version, but again, that's just a guess.

Either way, the hydro is a pretty beefy transmission, even in stock form. I know you mentioned a 392 Hemi... how hardcore are you going?

 

If your thinking of using the Hydro in your 33 Coupe something to consider is Ohio George used Hydro-Motive in his Coupe.

This is actually the Hydro out of Ohio George's coupe. It belongs to a buddy of mine

We picked it up from George a few months back. It started because he found the box that George kept the hydro in after it was switched for an Art Carr C6. So George said that the trans should be kept with the box. Also note the bell housing is for the 427 sohc ford and George cast it and still had the mold for it. He also got the original chrome starter delco made for it. Forgot to take a pic of the starter. It also came in it's own wooden box.

 

^^^That's just plain cool!^^^. What's with the extra little doo-dad flange welded to the extension housing? Does the starter motor attach from the "rear" of the bellhousing? I am Butch/56sedandelivery.

 

I'd think that either will have to be gone through and at least resealed if not refreshed with new clutches if needed. All that rust on the outside of the B&M is a bit spooky too as it may have been under water at some time or laying outside for a long time.

 

The tail housing was modified to use a closed tube driveshaft originally, if that's what you mean. The starter mounted upside down to the bell housing from behind.

 

Either tranny is very strong. The unit was designed in the late '40s for military tanks so the base tranny is very strong. That's one of the main reasons it was the first auto to take over drag acing. B&M was first working with Big John Mazmanian but there were many Hydro modifiers that were just as good.

Military version

This is the 1st gear lock valve that B&M patented to hold the tranny in 1st. Really didn't mean much since the Hydro uses a fluid coupling so has no low speed torque multiplication from a torque converter. It uses a quick 1st/2nd shift to simulate the torque converter function. Racers always started out in 2nd because of this. Other oddities include power flow in 4th that goes thru 2 paths making it almost like a lock up converter. Very efficient unit. Witness the hydro doesn't need a tranny cooler whereas the modern wonder boxes would fry without one.

 

I have read the same on here about hydro-motive buying out B&M then changing to TCI. It’s hard to find info about these but Gene in Salinas has been very helpful as far as rebuilding info. But I am interested in buying whatever one you don’t want!


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There's one on the Dallas CraigsList.....asking a lot of money but seams to have a adapter belhousing......don't know anything about the seller....

 

That hydro stick on Dallas Craig's sure looks nice, drumyn.....

 

Post it up boys !! That's how we learn.

https://dallas.craigslist.org/mdf/pts/d/euless-1960s-bm-hydro-stick/7047641685.html

 

^^^^1954 OLDS slant pan core was used by B&M with a Ford adapter. UC for Unblown Competition

 

Hell, I didn't even notice he has the shifter too, looks like a sweet deal....

 

I can't help you, but I found out last summer how much help there is here. A HAMBER even called a couple of times from Nebraska with invaluable help. My case was cracked and missing a bolting tab in side so it was replaced and now I need decals. Best of luck.

 

This one is now strapped to a pallet and headed north. Will be making its way into my 59 F100 behind a 324 Olds.

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Good for you Speedy! Another one saved.