Technical TRANSMISSION, B&M Hydro stick installation instructions

Yes, that valve you are holding is the first gear locker that the Spar Bros. invented. Since Dusal Range Hydramatics didn't have torque converters, GM designed a very low first gear and no provison to hold it there so the tranny automatically shifts to second @ ~10-15mph. This was the factory's answer to a torque converter. Modified B&M Hydros came with that valve but racers rarely if ever used it. On a strip launch, the need to 1-2 shift came up so quickly that racers started out in second letting the 1-2 be their 'torque converter' as GM designed it. Thus the thing that put B&M on the map had little use in drag racing, lending itself more to off road mud driving!

Incidentally, your valve is missing the plunger. I'll post a picture or two of how the thing goes in the tranny.

 

well I've put this out several times but since this post is hanging well I'll try again.
looking for a Hemi to Hydro adapter. at this point I don't really care how reasonable it is

 

I have a hemi-to-hydro flywheel for $300 plus shipping, but no adapter-- sorry.

 

i will surely be carefull when i dissasemble it. ive got a feeling that its most likely not much differnt inside than any other early cad single range of that era. but curiousoty is killin me sorry im a little slow on this one but the day after i got it i had to go to costa rica which is where i am now on the hotel comp. The other assembled hydro,s i have are chevy truck thats built and ready to go racin and 2 - 55 cad units and lots of internals left over from my dads hydro days of building them for strip cars bands and dual range valve bodies make up most of it though. its funny what you said about gettin info from old hydro guys ive had the same experence in that they dont even wanna talk about em and cant understand why i have any interest in them. On the tank hydro another thing i noticed is that it has a short tailhousing with a mount on the bottom just like my 55 cad units but its a short tail like most hydros and not 2 ft long like later cad.I suspect its just stock early cad but i dont know. Like you said there is alot to know about hydros. You mentioned brass clutch plates you mean like with no friction matt. bonded to them? Have you ever heard of hydro clutches like this? damn now you have my really really curious.

 

what ive come to learn about this perticular mod. is the best mod is to do is not modify the stock tube but instead machine the governor WAY down so your 1-2 shift comes in at around 6000 or so depending on how much you cut off. cause like you said there is other things for the driver to be doing 10 ft out of the hole than trying to shift to second because first is ridicoulsly low. Also i have a valve assy thats in a tranny i have its just not a cool lookin b & M one so i didnt post a pic of it . my thought on the first gear reason was more that these tranny's came in very heavy cars that were relitively under powered. If you look at the different ratios of the differnt cars you will notice that there all different and that comerical service vehicles and cadillac had the lowest first gear ratios. Its the job of the torus assy. to provide the function of the engine to continue running while the car is not moving while in gear . which is why it only has the duty idleing in gear and the 1-2 shift and is not in use after that. The 2-3 and 3-4 shifts are direct and do not use the torus. which also is why these trannys last and dont burn up there is nothing making HEAT most of the time. the spend very little of their life using the torus assy. I would like to see b&m's valve if you have a pic of it. Thanks

 

so if you were to cut down the vanes on the torus to raise the stall speed it wouldn't affect the normal driving?

 

I used a half dollar piece marked them about 3/4 inch from the center to get 3000-3500 stall,

 

Here is B&M's valve installed. When I first modified my tranny I didn't have a B&M valve so I made one out of aluminum bar stock and a piece of steel rod. Works great. Regardless, really is no reason for it in a drag car. Starting out in 2nd, allowing an auto 1-2 shift then manually shifting the rest works pefectly.



Also, here are a couple photos of the military version. Quite a bit different from the auto one. Has a cast iron bottom pan, different dip stick boss cast into the body. These things were used in military tanks during WWII so a little service behind a blown 400' engine is no sweat!

 

Wow, never saw a pic of a military unit-- thanks!

As for what I mentioned about brass clutches, I mean solid brass or brass-alloy clutch discs. I understand this is what were in tank trannies, as well as what the Dynaflow clutches were supposed to be.

I also understand that while they are good for high-heat, the brass shavings that wear off tend to clog up the valve body. Just what I've heard. I plan on having a small production run of Red Alto kevlar clutches done when I'm ready for them. But that sort of small production run type of thing is NOT CHEAP and I'm a long ways from needing them yet. Too many other areas of my project to concentrate on.

 

i am running a hydro in my 31 roadster. just scored a pile of n.o.s. hydro parts from a pontiac dealer. nice catalog. cadillac dave

 

I wouldn't say that. Just raising the stall speed affects normal driving! But besides that, I understand that the higher the stall, the more slippage at high RPM. Or maybe that should be rephrased to more horspeower being lost by the two torus halves not transferring it all. Remember that the drive torus moves the driven torus by basically fanning past it and the fluid getting pushed by the vanes. Cut the vanes down and they can't move the fluid as well. This is why the stall speed goes up before the car starts to move. You gotta rev the engine (and subsequently the flywheel, torus bowl, and the drive torus) higher to get the driven torus to start to move. At least that's my take on it, and my understanding. It just makes sense to me that the efficiency of the torus assembly goes down when you start shaving the vanes back for higher stall.

That being said, it should be noted that there are differences in the toruses from model to model and year to year. I have seen several different ones. I plan on starting out with the small 10-1/2" diametewr Chevy truck torus in un-modified form, and then only making modifications to the vanes if necessary.

 

You are correct, cutting the vanes raises stall speed but also decreases mechanical efficiency across the RPM range. Less fuel efficiency and more heat generation is the result. Hydros are super sensitive to vane cutting and as B&M stressed in their 60s sales literature, get the tori configured EXACTLY for the type of driving you plan to do. Cutting too much or too little for your application is disasterous. My recommendation for the street is get the 10 1/2" 'Chevy' torus and use it in the big Olds/Caddy torus cover instead of the larger big-car tori. Since torque generation is a function of torus diameter to the 5th power, the smaller Chevy unit will increase the stall speed w/o loss of efficiency at speed.

 

For folks using a Chevy engine, I think I'd recommend using the smaller-diameter 18-bolt Chevy torus bowl as well. I don't believe you can attach a large 30-bolt Olds/Cad/Pontiac torus bowl to a Chevy hydro flywheel. Unless you know different.

 

That's correct. Sorry, I am always thinking hemi!

 

I just got this unit behind my Lincoln 368 and I don't know a thing about them. I'm hoping this post goes forever...

 

great bit of info here,

Rocketeers

put together by the HAMB's own Peter Lombardi

 

scans lifted from http://www.jalopyjournal.com/forum/showthread.php?t=717614

posted by DualQuad55

 

Your Dad used to build my Hydros back in the mid 60's for my 40 Ford w/60 Olds engine.
Also had a 60 Corvette w/Hilborn injected 427, Tube axle & Olds rearend-Street Machine.
I have the 427 out of your Dad's 50 Olds & 50 Pontiac.
I talked to your Dad at Ed Hegartys Wake, had not seen him in 45 years. Quite a reunion of oldtimers.
I used to run into your uncle Claude in Napa all the Time.
Regards
Rick Rentschler
midyearvet@aol.com

 

I realize this is a very old post... and I thought of PM'n yorgatron but he hasn't been around in a while. In post #42 of this thread, left side photo at the top is what appear to be large tube bender. I have one, and was told that it was meant to bend throttle linkage on diesel trucks. My question... what application would this be used for on a Hydromatic? Shift linkage? Mine is big/heavy with maybe 16" handles. Name that tool please.

 

Did you say forever? I've gotta be digging deep to visit 9 year old threads but I am looking for a Hydro floor shifter like came on your Lincoln. I'm using a 61 Olds 394 with 56 Hydro in a 41 Willys and an appropriate shifter is proving elusive. I thought that B&M shifters would be more plentiful. Please help if you can.
Best regards,

 

That shifter in the picture you quoted is a Hurst Hydro/Gate shifter. About as rare as they come. Beefy shifter with a positive detent set up. The B&M Big Stick is a little more common, but still pretty rare these days.
Check out the Hydro Tech group for more info on these and other shifters. You'll have to join the group to see the threads: http://www.jalopyjournal.com/forum/social-forums/hydro-tech.671/

 

Heres my b&M hydro that came out of Mazmanians Corvette when it was put back to street use here in Minnesota, my buddy bought it from the guy after he pulled it out. it has the hurst hydro-gate shifter on it, the trans now resides in my 54 vette strait axle that also had a b&M hydro in it back in the day.

JEFF

 

One for sale in Fresno for $450 if anyone is looking. Not mine.
https://www.facebook.com/marketplace/item/1364361101389666/

 

I still regret selling my HydroGate. Such a cool (and rare) piece of B&M history.

 

You and me both. And mine was NOS in the box !