What trans will work well with a Cad 390 that originally had the hydro? What will bolt up? What needs an adapter? What about switching to manual? Ideally, what's the best trans and what will I need? I currently have the 261 Chevy with three speed Saginaw. As always, thanks a ton!
Other than the 390's trans nothing else bolts directly. Adapters are out there from the Wilcap and Bendtsen to put either a manual or automatic. I don't know what your puttting it in but I put a manual behind my 390. You'll want a trans that can handle the 430 lbs of torque that it can make.
the hydro is the altimate set up ! top gear is awsome tall for highway work. spend the cash and have it re-built. had one in my 34 5-window with a 390 caddy ! *****in !
It would be going in a '55 chevy pickup. That is, if I can sell enough stuff to buy the engine before somebody else, lol. I prefer a manual, but cost may prevent one. Good point about the torque. Roughly three times the hp and torque compared to the inline, lol. Thanks for the input. I've got a buddy with a cheap but good hydro.
King of Trucks getting a Caddy?!?!?!?! That WILL reinforce the given name! ALL HAIL THE KING OF TRUCKS!!!!! SDG Brett
I'm trying hard Brett! I've gotta sell some stuff to get it. A killer chromed out cad mill was always in the works. I finally have an oppurtunity to get a runner, just gotta scare up the cash before it gets sold.
---------------- You wrote - "Top gear is awesome tall for highway work". Huh??? 'Top gear' in a hydro is 'one to one' - *exactly* the same as in any other non-overdrive ******. It was the first gear in the 4-speed hydro that was lower than most other ******s that gave it an advantage. Mart3406 ===========================
My 390 had a jetaway style hydro not the same as the older hydro. I put a saginaw 4 speed behind it using a wilcap adapter. I was disappointed with the adapter but it should work. The saginaw may not be strong enough for the 390 but I had it and it can easily be upgraded.
Here are a couple pictures the hydraulic slave cylinder is from a s-10 and I just made a bracket for it.
Thanks for the input. I've got a buddy with a cheap but good hydro.[/QUOTE] You haven't seen expensive until that hydro goes bad and you start looking for parts and someone to help fix it! I went with the TH400 w the Bendtsen adapter and won't be losing any sleep over ****** trouble ever again!
The hydro I'm looking at is a low mileage unit a buddy has. Works pretty good, for now anyway. And its cheap. I'll be able to run that for a while until I can get a good strong Cad manual trans and flywheel. And that brings up another question. I ***ume the earlier Cad manual trans will not bolt up to the later 390 because of different bolt patterns? What do I need to make that work? Adapter from where? Flywheel? Starter?
Discounting the few '38s(or '39s?) that were made with a clutch instead of a hydraulic coupling, there were at least three generations of early cast iron Hydra-matics. Even in stock condition those units have/had truck level durability. On the down side: they are heavy; first gear is on the low side for a car with a lot of power; and the shifts are little strange compared to modern transmissions. While I don't dislike the early units, all things considered, and given the option, in a hot rod I would rather have a Turbo 400 put together with good parts than one of the earlier Hydra-Matics.
Hey Terd , check out Pattersons Hydomatic service on cabarrus ave. close to the sundrop plant. They spe******e in these trans. along with fordomatic etc. They can get all the parts and I think they are pretty resonable. You know a 331 caddy and hydro are going in the 31 coupe?
Thanks for the tip Tommy! Good to know a local source. I can't wait to see that A model come together. Its going to be rad! Thanks everybody for the info!
the factory Hydromatics run like pigs..especially the lower gears. If you want to go automatic get a wilcap adapter and a TH 350 and you'll be happy.
The dual-coupling ('56-'63) Hydro isn't a bad trans, it's not as strong as the earlier ones, but if you're going to drive normally it should be fine for 100K or so; mine the only issue I ever had was a spring in the internal shift mechanism broke, so I had no detents - it would go into gear, you just couldn't feel it click in - which cost like an hour labor and less than five bucks for the part to have done. With 4 speeds it's pleasant to drive, you don't have to pound on it to go like stink either.
Terd, the ultimate Hydro, the one that B&M became famous for, was used on the early Caddy 331's and Olds. The 55 331 is the only year that you get that Hydro and the block without the extended bell. The later will do the job, it did for Cadillac. I'd only get a adapter to run a manual trans.
Terd check out the wilcap site. It's says the adapter to a Chevy MT Adapter Kit comes with Adapter plate, Flywheel, Pilot Bearing Adapter and fasteners. ** Starter is Mopar Small Block (318, 340, 360) (Not included in kit) Note 1.. Matched Chevrolet transmission and Bellhousing. 10.5" Bell is recommended. Note 2. Flywheel is drilled for 10.5" B&B/Diaphragm bolt pattern. Clutch disk is 10.5 with your transmission input shaft splines. That should pretty much give you everything you need to hook a T5, Saginaw or Muncie behind that 390. If I were you I'd be gunning for a M21 or M22 eventually so you can really drive that thing!
Imho, an old M-20 Muncie 4-speed will do you great, but no OD tho. Install something like 3.00 reg's under her for good high-speed road cruising. (I dearly love my stock 3.31 posi under my '67 Camaro). pdq67
For the record, I could care less about overdrive or high speed highway cruising. 99% of my driving is around town with an occasional two hour road trip every two or three months. I don't mind cruising at 60-65 instead of 75-80. My preferences include a manual trans with the easiest and cheapest install costs along with being strong enough to handle the added torque of the Cad mill. Thanks everybody for the great info! I really appreciate it!!!
The original Cad-LaSalle trans you asked about was used back then because it was one of the strongest available, and had performance-friendly ratios. But unless you want that trans for nostalgia reasons, I would go with a Muncie, or a T-5 with appropriate ratios. I think you would be happier with even the weaker Saginaw or older T-10 than the Caddy trans. The Cad-LaSalle had an unsynchronized first gear, but you can get used to that. What you mostly find is the later side shift versions intended for a column shifter. In those transmissions the 2-3 shift lever and slotted "****on" that moves the 2-3 synchro are easily damaged when the trans is used aggressively. Replacing the original bronze "****on" with a steel one helps, but it increases wear on the synchro, and only postpones the inevitable. Due to collateral damage to the fork, once you fail one ****on the next one fails easier. The earlier and rarer Cad-LaSalles were floor floor shift units. They had the same internals as the later transmissions, but had a different case. Those transmissions had shift rails and more substantial shift fork arrangement. This doesn't mean the later units are unusable, just understand they will tolerate less child abuse than the floor shift version. All the Cadillac units I have seen had extra-long tailshafts. Some Oldsmobiles(and possibly other GM cars?) used a version of the Cad-LaSalle trans, but with a shorter tailshaft. I have never tried it, but I am told the shorter Olds talshaft pieces can be installed in the Caddy trans. At one time Hurst made a shifter for the side shift Cad-LaSalle, but I'm sure it has been decades since the last one of those was made. Ansen also made a shifter for that trans, but it wasn't made as nicely as the Hurst.
The shift points between 3rd and 4th are what i am talking about. third gear winds way out, hit 4th and rpms' sound like they are falling on their face. you really gotta wind out third gear to keep the rpm's up there. My motor and trans were out of a 1962 caddy. My rear gear was a 410 ford. 80 mph on the freeway was no problem, all day long.
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