MOPAROFFICIAL
Oogliboogli
So you got your new Fast rate cam and you're stoked. You flip the lid and pull out the instructions... and it tells you that it requires a prticular valve spring... oh?...okay.. a double spring as a matter of fact. You read further into the instructions and it tells you to break the camshaft in by removing the inner spring and only running the outer springs...
.............Uh oh..........
But wait, do you even know what the outer spring by itself rates? What seat pressure? Open pressure? ....well? Do you??
You don't...
Unless you have a rimac aka "spring tester".. you have no idea what the pressure is or if it's even sufficient for a cam to survive a break in. ..or how about the little "womp womp" of throttle you give it ..before shut down and inner spring reinstall...
Well.. you would be shocked to find out that the outer spring alone is MAYBE 90lbs seat and 175-190lbs open/full lift all the way to coil bind!
Proper break in procedure, not necessarily psi , is what's most important. Proper lube, fuel primed,oil primed, instant spark... are the main keys to that procedure of a properly built and ready to run engine.
Consider the idea that you could very well be doing harm to your brand new camshaft by only running the outers.
Example...a common 140lb @1.80 315 open spring 'assumed made by the same manufacturer p*****r and reboxed by Hughes, engle, paw..'yes they're that old' and maybe even Howard's...'
80lbs psi installed ...
175-180lbs open @500
Would you break in a .573 lift solid with less than 250 open? Even less than 200?
Let alone 80 seat.
2200-3000 rpm.
Be safe out there.
Know what you're doing before you do it.
.............Uh oh..........
But wait, do you even know what the outer spring by itself rates? What seat pressure? Open pressure? ....well? Do you??
You don't...
Unless you have a rimac aka "spring tester".. you have no idea what the pressure is or if it's even sufficient for a cam to survive a break in. ..or how about the little "womp womp" of throttle you give it ..before shut down and inner spring reinstall...
Well.. you would be shocked to find out that the outer spring alone is MAYBE 90lbs seat and 175-190lbs open/full lift all the way to coil bind!
Proper break in procedure, not necessarily psi , is what's most important. Proper lube, fuel primed,oil primed, instant spark... are the main keys to that procedure of a properly built and ready to run engine.
Consider the idea that you could very well be doing harm to your brand new camshaft by only running the outers.
Example...a common 140lb @1.80 315 open spring 'assumed made by the same manufacturer p*****r and reboxed by Hughes, engle, paw..'yes they're that old' and maybe even Howard's...'
80lbs psi installed ...
175-180lbs open @500
Would you break in a .573 lift solid with less than 250 open? Even less than 200?
Let alone 80 seat.
2200-3000 rpm.
Be safe out there.
Know what you're doing before you do it.
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