comp cam springs

[Snake]

Ok my cam info says to install there 901 springs for there cam.during the camshaft break-in cycle remove the inner valve springs to help prevent premature lobe wear.After break -in install the inner spring.this sounds like a bit of work after everything is button up.Did you all do this or can it be safe enough to skip this step.

 

[fishy68]

It HAS to be done. Period!! If you don't I can almost guarantee you'll be installing a new cam again next week. Reason is with the high spring pressure of 2 springs it won't let the lifter rotate when breaking in and that'll cause it to wear out super fast. In as much as 10 miles in some cases. Yes it is a PITA but it's the only way to make sure your cam lives a nice long life and your warranty is good.

 

[70aarcuda]

comp 901 are a single spring...there is no inner spring...

you may have a damper which is not a spring.


there is no guarantee if you use the inner spring that it will go flat on you....the last 4 solid lifter cam i have installed had dual springs...i did not take out the inner...they are still running years later....

you need to have it properly lubed...the motors oil pump primed...the engine needs to fire right away....

 

[Snake]

Ok how do i remove the spring after the break-in to install the outher spring remove the head.Thanks

 

[Snake]

Ok so I am fine with the 901 perfect.

 

[fishy68]

70AARCuda
Good catch on the 901's being single springs. I wasn't familiar with them.

Also you mentioned you didn't remove the inner springs on the last 4 solid cams you broke in and had no problems. Keep in mind solid cams run lash which gives the lifter a chance to rotate where-as a hydraulic lifter has no lash and alot of spring pressure will not allow it to rotate properly. It is especially worse today with the levels of ZDDP reduced and cams being much more aggressive than yrs. past. Have some guys gotten away with breaking in a hydraulic cam with dual springs? Sure. Some have because even some dual springs don't have a great deal of seat pressure. And sometimes you just get real lucky. But to be safe it's always a real good idea to remove the inner springs when breaking in a new cam. After one flattened cam because you were too lazy to do the extra work of installing inner springs after break-in you think twice about trying to do things the old fashion way. I know a stubborn buddy of mine did after flattening 2 cams.

 

[dodgetkboy78]

I have broken in dual springs, and really stiff springs with hyd lifters. I have made two snide remarks now about everyones favorite cam manufacture, so I wont again.
HOWEVER.
I start out at .010 lash with HYD cams running big springs. The 273 adjustable rocker arms are so cheap, how could you not use them???? Worth a million lobes and valves.

 

[moper]

No egnien on todays oils should be fired with the inner springs in place. All manufacturers (except for MP who have ancient grinds anyway) tell you to do this. It takes about an hour after the cam's broken in to add them. I've driven cars for 25 miles without the inners. The only issues arrise if you over-rev them. The 901-s as said have the flat wound dampner inside them. The true dual assembly has the smaller round wire spring inside that dampner.

 

[dgc333]

Ok how do i remove the spring after the break-in to install the outher spring remove the head.Thanks

No need to remove the head. You either gut an old spark plug and weld an air fitting to it (or use the hose from a compression tester) and pressurize the cylinder with air or get a length of cotton close line rope and stuff it in the cylinder through the spark plug hole (don't forget to leave a piece hanging out) and slowly bring the piston to TDC. Either way will hold the valve in place while you remove the spring.