Little M cam bore

[MCEcomp]

Hello

Could some one please tell me what size the cam tunnel is on little M block 31131213, these are the PRO blocks with 50mm cam bearings???

Can i run a 55mm cam in it with a babbit bearing?

Thanks
James

[Awesome Bill]

how much stroke are you going to run?

[MCEcomp]

I ts 3.33 stroke.

But whats it matter just want to know what the cam bore size is for that part number?

[CNC BLOCKS]

I ts 3.33 stroke.

But whats it matter just want to know what the cam bore size is for that part number?

The cam bore size is 2.283 and if you use bearing P/N Durabond GMP-55-T it will fit in that same bore and you can use a 55MM cam core.

That seems to common now as a lot of guy like the babbit bearing as it takes some harmonics out of the valve train.

[MCEcomp]

Thank you Carl

IMO with really high spring pressures in a drag race engine where you can prime oil system, id rather a 55mm core in a babbit bearing than a 50mm in a roller...

[Awesome Bill]

It matters with anything larger than a 3¾" stroke, you have to cut the rod even worst with a 4" stroke. So with a 55 mm cam core, then small base circle it to .900 opr even .875 you still have junk. The idea is to have a thick cam core to prevent twisting we get with the small base circle stuff. Even had cams break @ .875 so we try to stay with .900. But with that little stroke, you have nothing to worry about. The roller bearings do reak havic with the camshaft and lifters. Harmonics work on them. I would use the standard cam bearing @ 55mm, you will be better off.

[malihoochie]

Jesel offers a babbit bearing #BRG-60110P that is a 55mm ID to be used in that 50mm roller cam tunnel.