Roller cam bearings

[nhramnl]

Originally Posted by Mark Ugrich

Are there any real advantages to using a roller vs. a Babbitt bearing? I’ve never had any personal experience using them.

Really interesting question. A person's intuitive reaction would be "of course, look at things like roller lifters and rockers", but I'll bet there aren't many engine builders who have actually done an A-B-A comparison of cam bearings.

[SSDiv6]

Babbitt is the only way to go.

Roller bearings, when turning the camshaft on the engine stand, the camshaft feels drag free and it turns easily. However, during engine operation and load, there is more drag while turning. When using high spring pressures, the loading may cause the needle bearings to fail.

[Todd Gross]

The biggest advantage of roller bearings are that they do not need pressurized oiling. So in most V8's you are blocking off 5 oil leaks inside an engine.

[HP HUNTER]

Originally Posted by Todd Gross

The biggest advantage of roller bearings are that they do not need pressurized oiling. So in most V8's you are blocking off 5 oil leaks inside an engine.

YES

[Mark Ugrich]

Originally Posted by Todd Gross

The biggest advantage of roller bearings are that they do not need pressurized oiling. So in most V8's you are blocking off 5 oil leaks inside an engine.

So the advantage would relate to less oil coming from the cam journals, reducing windage in the crankcase?

[SSDiv6]

Originally Posted by Todd Gross

The biggest advantage of roller bearings are that they do not need pressurized oiling. So in most V8's you are blocking off 5 oil leaks inside an engine.

The roller bearings still need some pressurized oiling; they do not oil by themselves and although there are claims oil splash is enough, I have seen enough damaged roller bearings due to lack of oiling especially on endurance engines.
If you have the right cam journal an lifter bore clearance, you will not have to worry.
Yes, they are known to create harmonics issues and it shows in Spintron testing.

[Jim Bailey]

Not Legal in Stock ,,, correct ?

[B Parker]

Originally Posted by Jim Bailey

Not Legal in Stock ,,, correct ?

Jim I was thinking the same thing. Barry

[Signman]

What you may consider is isolating the camshaft by forming a closed tunnel with oil return run directly down to the pan. Cam, lifters and bearings see plenty of oil maybe too much but would not fall into windage with an internal or external oil return line or limit the fall to the rear only for not 100% effect.

When looking at this a few years ago it's difficult with SBC without a lot of work I spent hours cutting and filing PVC tube to fit planning to pin and epoxy but issues with connecting rod clearance made it too much work at that time and became evident sheet metal would have been a better choice.

When searching cases where I could see this actually done this was with a Ford with dry sump much easier to control putting oil in the front and return in the back the tunnel would be filled or nearly.
Great idea to apply to a stocker there would be HP there but the labor cost would be more than most would pay but a crafty guy doing it for himself............