Camshaft roller bearings
 

Are you allowed Roller Bearings on the cam in Stock?
Thanks.

Re: Camshaft roller bearings
 

Is it for safety??????????????

Re: Camshaft roller bearings
 

Do they allow 52 or 55mm cam cores?

I always ask my Div Tech Director questions like this. Does the rule book mention them? They tell me, if it doesn't say you can, you can't.

Re: Camshaft roller bearings
 

Not to open up the ant farm but I would chalk this up to the lifter rule that's just been clarified even though "some" been running them for years...same for the .842/.875/.904 dia. everybody knows whats supposed to fit where....but

carry on with the discussion

Re: Camshaft roller bearings
 

Re: Camshaft roller bearings
 

J.R.: Roller bearings only if the engine was originally equipped with them. Rollers in rollers, babbitts in babbitts. Cam journal size can be changed.

Stay warm. -Al

Re: Camshaft roller bearings
 

I do a lot of cam tunnel blue printing and roller cam bearings seem to be a thing of the past. Roller cam bearing transfer alot of harmonics though the valve train.

I see alot of BBC cam journals (2.120 housing bore ) for the OEM GM blocks using the GMP-1

I have custom 55MM babbit cam bearings for a 2.282 housing bore which seems to be very common in SBC, BBC, and the SBF

What block was the OP talking about.

Re: Camshaft roller bearings
 

What block are you talking about ?

Re: Camshaft roller bearings
 

Re: Camshaft roller bearings
 

A 010 block you can't go with a 55MM cam it will push the oil band of the lifters up out of the lifter bores because of short lifters bores. Plus going to a 55MM with Babbit cam bearings you have to machine the cam tunnel to 2.282 and when doing the annular oil grooves in back of the cam baring there is a good chance of getting into the water jackets.

The Dart SHP Pro block comes with BBC cam tunnel and .904 lifter bores, I have gone to 55MM babbit cam bearings in those blocks with no problems.

What lifters can you run ? Roller, Flat tappet ?

Re: Camshaft roller bearings
 

Re: Camshaft roller bearings
 

How much lift ?

Re: Camshaft roller bearings
 

Re: Camshaft roller bearings
 

If thats lobe lift the BBC cam core would work fine. 55MM would not work.

Re: Camshaft roller bearings
 

Re: Camshaft roller bearings
 

Less flex going to the BBC cam core. If your getting up around .700 plus lift the bigger cam core will give you a better profile to work with.

On my flat tappet circle track engines I use alot of BBC cam tunnels as I can use up to a 1.9 rocker ratio and not take the nose of the cam off.

Lock your dist. up and check your timing it will retard do to flex. Do the same with a Ford where the dist. in on front of the engine !!! No change.

Your cam grinder would have the advice you need.

If your dealing with GM blocks cam tunnels and lifter bores are all over the place which will effect seat timing events (more so with roller lifters) and if there not right it will create an imbalance in the intake and exhaust and will hurt cylinder pressures as well.

If your dealing with a shop that cam Blue print the cam tunnel and lifters bore the end results should be good.

Thats why I posted this link earlier.
http://digital.enginebuildermag.com/...1-ae5dfcff4c38