i think you have the wrong idea about breaking in the cam, as soon as the engine fires you must run it at 2000-3000 RPM for 15-20 minutes, you arent supposed to start it, tune, adjust the valves and do this step later, of course you will do the fine tuning the timing and the carb after this cam break in but you just need to get it in the ballpark and fire it up and run it

if the engine is started and kept at idle, not enough splash oil will get to the lifters and the slow speed wont help rotation and it will eat the cam, hopefully yours is still okay but you better crack open a filter and check

To properly break in your cam, first be sure your carb bowls are filled if so equipped plus have the timing and valves set as close as too right as possible so that it fires immediatly,ideally it should'nt turn over more than a couple of times before starting then whatever you do don't let it idle if it's possible do this outside so that if you have too you can spray the radiator with water too cool it down if need be and of course a friend should do this.When it does start have that friend check for leaks then you want to VARY the engine speed between 2000 & 3000 rpms or there abouts, what this does is it pushes the lifters up in their bores and makes them spin as the cam is ground on a 1* taper off of 90* by this it accomplishes that spin.  Again I have to say vary the rpms if not keeping it at a constant speed will not allow that splash as was stated in the other post.LOL   

Cold adjust the valves very closely, then start it and emidiately start breaking the cam in, 1500 rpm to 2000 varying the speed for 15 minutes. Then change the oil and move on. You can do the tuning and adjustments at the same time. Watch the oil pressure and coolant temp closely.

My experience with Big Block Chevy engines would entice me to give you this advice. After all this time, the break-in lube will still be ok at this point. No, don't try to adjust the valves at 2000 rpm. Not only would that be impractical, but would change the lifter-to-lobe resistance during break-in, and consistancy during the break-in period is critical. If you feel that the lifters are reasonably close at this time, go ahead and crank the engine and let it run for a few minutes at about 1500 to 1800 rpm. Then shut the engine off and remove the valve covers. With a hydraulic cam, set the lifters at 0 clearance, and then add about 1/2 to 3/4 turn. This should create the proper lifter preload. And as far as thinking too much, it's good too err on the side of caution. Happy motoring.    

Most agreed.  

TO Blumun53. I rebuilt my 305 in 2001 using your method.(coincident) Nevertheless,My motor has 75,000 with no Problems concerning oil pressure(40psi at 65 mph;15psi at idle)or lifter noise. Hope this helps peter4vr. GibTG, I enjoy your responces and knowledge concerning mech. issues.      PS. I love dirt track and drag racing. I USE VALVOLINE 10/40  Durablend.If 10/30 can be used in my 305 safely(winter driving)please let me kn
ow.THANK YOU ALL.  carfulmechanic