Roller Cam Bearings

dirtnap · Post by **dirtnap** » Sun Aug 29, 2004 2:34 am

As I sit and look at this 50mm bearing setup and this custom cam and the block I'm about to bore to fit this mess .I'm wondering to myself why I need a custom cam why doesnt someone service a bearing for the stock size cam journal?I have to bore the block no matter what but it seems like it would be a great idea not to have to buy a special cam too.Isnt the bearing the cheapest part ? I dont have alot of roller bearing cams so I cant experiment alot with them.Now if they used stock mains It would be so much nicer for me So does anybody make a bearing like that ? Thanks for reading my gripe I now return you to your regularly scheduled programming.

learner · Post by **learner** » Sun Aug 29, 2004 10:13 am

Even if they made bearings to fit existing cam journal sizes you would still have to have a different cam due to the Rc required to run the roller bearings.

CNC BLOCKS · Post by **CNC BLOCKS** » Mon Aug 30, 2004 7:58 am

Even if they did make roller bearings to replace the stock bearings there would not be much of an advantage, By going to the bigger bearing you can get a much better profile camshaft, Some of the cup guy are using 55MM cam bearings in the chevys and the Fords are 70MM.

Stocker · Post by **Stocker** » Wed Sep 01, 2004 12:05 pm

Other than being able to run a bigger cam profile, and a bigger core, would there be any gains with running roller cam bearings in a small chevy with a fairly small cam ... ? Keep in mind, this application is a hydraulic cam with .400 lift...
Thanks, Mike..

Adger Smith · Post by **Adger Smith** » Wed Sep 15, 2004 9:10 pm

Oil Control

speedtalk · Post by **speedtalk** » Wed Sep 15, 2004 9:55 pm

Adger Smith wrote:Oil Control

Exactly! You could then cut down the pressure side of the pump. Hey Adger, Thanks for joining the forum and your economy with words

Guest · Post by **Guest** » Wed Sep 15, 2004 11:11 pm

I use to look at the roller cam bearing as a waste of money but what i did not realize was the side benafit of reduced oil pressure.I keep wondering why we have not prosued the complete roller engine.A few years ago at PRI one of the big rod companys had roller rods they where a cracked rod big end design.They said they had tested them in a cup car when they still used qualifying engines.He said they had the oil pressure down to 30 LBS at one time when testing.I have not seen them since.

mike

Guest · Post by **Guest** » Wed Dec 01, 2004 7:29 pm

I think the reason that you don't see roller bearing motors is because of metal to metal drag. The motocycle engines used to come this way and they are getting away from it. A plain bearing motor at speed "should" float on a cushion of oil where roller bearing will always be in contact. Todd H

CNC BLOCKS · Post by **CNC BLOCKS** » Wed Dec 01, 2004 11:23 pm

We have a Ford block in the shop that came from Roger Penske that has std Ford Cam bearings and all the other blocks from them were all roller cam bearings.

jacksoni · Post by **jacksoni** » Sun Dec 19, 2004 10:14 am

I have some roller bearings for a new engine I am building. A new deal for me and I looked up the source numbers. I think they were originally for a transmission application, now adapted to cams. Thus, I assume the lack of sizes for standard journals- not enough market to make them special.

CNC BLOCKS · Post by **CNC BLOCKS** » Sun Dec 19, 2004 11:26 am

It is my understanding at the PRI show there is a slider bearing or babbit bearing for a 2.283 cam housing bore for a 55MM core, I will give Calico a call Monday as they are stocking these size bearings.