Cam break in question.

[1967coronet]

My new comp cam instructions advise 260/270 lbs. open spring pressure at break in.
My crane springs # 99839 are advertised as 280lbs open. Is that extra 10lbs going to trash a lobe ? or do I need to switch back to the oem/stock springs for the break in.
I have not had to break in a cam in 40 years and a lot has changed, used to just Lube them in STP and fire them up dbl springs and all, never did wipe a lobe.
I am using the comp cams install lube and oil additive this time.

 

[68383GTS]

I would install the old weaker springs for break in. That is what Comp cams advised me to do on the last cam I bought from them.

 

[Challenger340]

290# is the maximum upper limit we use on the Dyno for Flat Tappet Cam run-in....260-270# preferred and with lots of Zinc in the Oil. We typically remove the inner V/Spring to accomplish the lower spring pressure for Flat Tappet Cam run-in.

Today's Oil is much different that Oils of yesteryear, NO additives as banned by the epa, and Today actual "Break-in" Oil from LUCAS etc is highly advised.

260-270# open V/Spring pressure should run-in just fine, keep the rpm up between 1800-2100 rpm(varying a bit to through Oil different places) for 20 minutes, and again, Lots of Zinc additive in the Oil, or actual High-Zinc Break-in Oil.

 

[wyrmrider]

best to use a break in oil blended by a blender
lower dispersents and detergents helps from washing away the EP
do not add zink to an SN oil
Brad Penn is a grade 1 oil with additives
a non or low detergent break in oil would be best
no synthetic for break in