In my opinion, none. The Stude rockers give you adjustability, but that's all. I can't quote rocker ratios right now but you lose lift with with them. Mainly with the 365 & 390's. Adjustable push rods would serve you better & the stock valve covers would fit. My opinion plus $3.50 will get you a cup of Star Bucks coffee.
Cadillacs used hydraulic lifters, Studebaker used solid lifters. Here are adjustable Studebaker rocker arms as used on Caddy 331 engines. You only use he rockers themselves. https://www.jalopyjournal.com/forum/threads/studebaker-rocker-arms-on-331-cad.218663/ https://www.jalopyjournal.com/forum/threads/studebaker-rockers-on-stock-cadillac-365.987089/ https://www.jalopyjournal.com/forum...cker-arms-as-used-on-cadillac-engines.983586/ https://www.jalopyjournal.com/forum...er-arms-cadillac-olds-studebaker-sold.974055/ https://www.jalopyjournal.com/forum/threads/lets-talk-cadillac-331s-365-and-390s.1015067/ https://www.jalopyjournal.com/forum/threads/lets-talk-cadillac-331s-365-and-390s.1015067/page-8
Thanks for the input, I know all about the adjustability,the fact that you only use the stude rockers themselves and they fit the Cad shafts,and the fact that you lose the lift also the way the ratio is. This is why I was asking,I actually see no benefit myself other than the adjustable side of things. To me losing the lift is going backwards I would of thought,maybe I’m just not seeing something? Thanks for the list of old threads on the subject,I just read them and all appears clear now,seems if you machine the heads or block,using the adjustable stude rockers can help sort out the geometry of the rocker gear to valve issues. You also need new pushrods as well due to the ball cups of the stude rockers being larger and possibly the length after matching may need changing.
It used to be a common hop up trick to change from a hydraulic lifter cam to a solid lifter, high lift cam. Studebakers had solid lifters and adjustable rocker arms, so they put the Studebaker rocker arms in the Cadillac when they went to the solid lifter cam. In those days hydraulic lifters pumped up at about 4500RPM and performance poohed out. With a solid lifter cam you could rev to 6000RPMs or more. If the cam grinder knew you would be using Studebaker rockers they could grind the cam accordingly to make up for the lesser leverage. The alternative was aftermarket lifters from Gotha and others, that were a lot more expensive.
Late breaking news. After my earlier post (post #3) this morning, I drove to South Bend, IN & attended the Studebaker Drivers Club meet & swap, a national event. It's only a 25 mile drive for me. I talked to a couple of Studebaker parts vendors, one them being a racer the other a retired toolmaker. Both seemed to be well versed in Studey engines. I talked about rocker arms & they both said the stock ratio was 1:5 to 1. They also said the ratio varied somewhat & usually on the low side. The toolmaker laid that off to worn out tooling, as Studebaker was in money trouble during it's later life. The stock '55 to '66 Cadillac rocker arm ratio is 1:63 to 1, so there is no advantage to the Stude rocker. I don't know what the '49 to '54 Cad rocker ratio is. An interesting note is the Racer vendor had for sale on his table Harland Sharp aluminum roller rockers for Studes in 1:60 & 1:65 ratios. These as we know will fit the Cadillacs. I also believe you could contact Harland Sharp in Ohio & have them fabbed for your Caddy. Also on his table was a set of refurbished late Stude rockers, shafts & stands for $90.00. Overall it was worth the time this morning.
Thanks 42merc, more good knowledge for the Cad guys. A lot to learn if one is willing to ask and listen.
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