I will be building a 455 with big valve "E" heads and am looking at a DMR-1530 cam from Dick Miller Racing.Dur@50 Dur@006 Gross/Lift Lobe/Sep

230/236 274/286 .522/.522 112/108 is the specs. As you can see it has a .522 lift....what will happen if I use a stock non-adjustable rocker arm set up? Will it just have a little more lifter preload?

 

Coil bind and bent pushrods collapsed lifters wiped cam lopes.
Oldsmobile engines require special attention to the valve train anytime you go above OEM.
As with any modification it all needs to cumulate as a matched package to optimize performance and stay away from broken parts/wasted $$.

Give Bill a call at BTR.

http://btrperformance.com/

 

You can clearance the rockers so that they won't bind on the fulcrums at full lift and at zero lift but you will have accelerated wear due to the higher valve spring load of your new valve springs needed with the replacement cam. Harland Sharp makes a bolt in replacement set up that won't require any machine work and will handle the lift and spring pressure. Make sure to check valve train geometry upon assembly.

 

There was a time when next to nothing better than stock was available for Oldsmobile valve train.... I built a 425 with G heads, 590 lift cam stock rockers and bridges. I used adjustable pushrods to get proper lifter preload....no issues at all...