I,m putting together a 512 and have run into the cam won,t fit in the cam bearings again. i putposely didn,t have this block boiled to avoid having to replace the cam bearings because in the past that has always caused cam fitting issues. i used an old cam and cut across the journals to create a little clearance but the new cam wont even start in the bearings. i measured the new cam journals and measured several old cams i have. the new comp hydraulic is .002 bigger on every journal compared to the old cams. this new cam is not oversized compared to the FSM #,s installing new bearings wont cure this and really will only make the fit worse. man this stuff is frustrating. what i need is a new cam core to cut the journals on but that wont happen so any ideas?

i hope you can call the cam co and get some answers!/help.

I have in the past put in an old junk cam to smack down on to size the bearings.but if the new cam is bigger sounds like it was ground wrong.

the new cam journals #,s would give .002/.001 clearance using factory spec bearing i.d. #,s it just seems the block bearing bores are undersize causing the clearances to tighten up. i can lightly tap the cam in the bearings but it won,t turn at all. anybody chuck a cam up in a lathe and wacked a thou or 2 off the journals?

probably not what you want to hear but, I think you need to look into the bore's in the block and have them resized/honed.

it may only be 1 bearing that is tight.do you have a snap guage to mic the cam bores?are thay coated bearings?

i used a digital vernier caliper on the front bearing and it checks to be the same size as the cam journal, no clearance at all. the bearings are factory 1977 oem stuff. do you engine shop guys with the rottler cnc stuff touch up the cam bearing bores and if so how much do you find them off by?

Just poilsh off the cam. It would not be easy to hone the block, cause every bearing journal is diff.

after installing the cam with 0 clearence check to be sure the bearings did not move in/out or turn.i had that happin.