R1 block #5 cam journal undersize

[supernova1969a]

Just got an R1 and noticed camshaft journals #1-4 are 2.275 but #5 is 1.1875 standard hydraulic 318 Babbitt size. Anybody every seen this, does someone make a special can? Thanks

 

[dodgetkboy78]

The back is the same, but I think the big holes are for a large roller cam. Never had a R1, but remember something about special cams..........

 

[moper]

If all the cam bearing bores are the same size, I believe you have a roller bearing block. I wasnt aware of #5 being a factory type but it's possible as it only supports 1/2 the load and is the low stress end rather than the middle or drive end of the cam. That means yes, you need a special cam blank used and you need to buy the bearings.

 

[dodgetkboy78]

Doesn't it use a roller thrust plate too?