1950s Roller Lifters

[5390john]

Awhile back I somehow got on the e-mail list for "Hagerty News".
This week there is an article about roller lifters and their various benefits.
I am thinking about having the stock 331 in my '55 CDV rebuilt at some point way down the road and I am curious if anyone out there in Caddy Land has ever found roller lifters that will retrofit an otherwise stock 331, or even better, rebuilt a 331 with them and share their results.
Anyone?
John Adams

[TJ Hopland]

What do you hope to gain and what are you willing to spend to get there?  I kinda doubt anyone has ever made any sort of retro kit for a 331 so unless they happened to be the same as the 472/500 (or some other popular engine that happens to have the same dimensions) its gonna be a custom job on several levels. Even if there is a lifter and guide system that fits you are gonna have custom stuff to work out like different length pushrods and a custom made cam made for rollers.  Can it be done?  Probably but is it gonna be practical?  Even some of the engines that there are kits for often require sometimes extensive machine work to make em work.

Here is the piece, I'm a customer and get plenty of crap from them but I checked my email and its not there, had to search for it.  That doesn't make sense?  Not that I want more crap from them.

https://www.hagerty.com/media/maintenance-and-tech/the-little-rollers-that-changed-engines-forever/comment-page-2/

Here is the video that it appears to reference

https://www.youtube.com/watch?v=y2TuR4fR1W0


One little nugget that never gets mentioned and is barely mentioned in the video is there are still a ton of engines that don't use rollers. I'm not sure what the official name is but the part the cam rides on seems to be called a 'bucket'.  I assume the name comes from that they are like an upside down bucket over the top of the valve spring.  I think in some cases these have a hydraulic lifter like component and other cases they kinda look solid. 

Either way cam is riding on a smooth hunk of metal, not a roller. That kinda shoots the argument that no modern oil has to deal with that sort of contact, they obviously have to.  Now do those engines require a special oil?  That could be a reasonable question to ask.  I have never tried to figure out which engines those are and look up to see if or what special oil requirements they may or may not have.  Again I have not carefully researched the topic but it appears like every brand has some engines in their lineups that don't have rollers, usually the lower end models.

[5390john]

Thx for the in depth response!
I thought the idea of roller lifters was a possible easy upgrade to an engine rebuild, possibly requiring a different cam lobe profile or custom pushrods, but hopefully not.
My thought was that rollers would add a little smoothness, maybe better acceleration, that sort of thing. I would not consider doing it if it required a custom made camshaft or other highly engineered components, but would consider it if necessary components were available out of a catalog from known, reputable suppliers at reasonable cost. 
John Adams   

[The Tassie Devil(le)]

The only positive with Roller Lifters is that you don't have to use the "old-fashioned" Oil with Zinc.

With Rollers on the Cam Nobes, there is no sliding action as with the Flat Tappet Lifters because the roller simply rolls on the cam lobe.

And, as has been stated, the requirements of a new cam for the Rollers to work on will be expensive, along with the rest of the requirements.

The only reason Rollers are used in engines that were designed for Flat Tappets is that the use of them enables ultra high pressure Valve Springs, longer valve opening and closing, plus higher revs.   This then needs Rev Kits to keep the rollers from floating at high revs.

Bruce.

[Moody]

With roller lifters you have to use a roller cam. Good luck ever finding one off the shelf. For me it's many more parts to fail potentially.

["Cadillac Kid" Greg Surfas 15364]

Order of magnitude costs above that for a flat tappet cam and lifters for the cam (custom grind), lifters, push rods, valve springs and cam buttonwould be in the neighborhood of $2,500. Rollers in Cad motors are beneficial when you are pushing the motor to it's high performance limits. I've attached a couple of shots so you can see the difference in cam proviles between a stock cam and the 250 degree (at .050") in my "hot rod".
Greg Surfas

[bcroe]

With rollers you do not need to break in the cam? 
I think they are claimed to reduce friction, but I
see the main advantage as using the latest oils. 
Perhaps they would be useful in getting more rpm
from my low compression engines?  Bruce Roe

["Cadillac Kid" Greg Surfas 15364]

Rollers allow much more aggressive cam lobe design meaning faster valve opening and greater effective flow. As far as more RPM it takes revamping the entire valve train (lifters, push rods, valve springs and rocker arms ) in conjunction with increased air flow(carb intake manifold and head work). In fact with my Cad Co 300ss flat tappet cam, peak HP came at about 5200 RPM. When switching to my 255 degree roller, peak Hp was at 5700. The HP went from something like 450 Jo to near 600
Greg Surfas