hillbilly pony

Why is there a difference in stress placed on the block by hydraulic rollers and solid rollers??

woodsy

Spring pressure with solid rollers is in excess of 225+lbs of seat pressure and 600-700+ open pressure, so this pressure is loading the cam, the cam tunnel and onward

Portmaster

If you are worried about the solid roller busting up your 351 block I wouldn't worry about it. The stress you get in the cam tunnel won't be the deal breaker unless you have gone way to far already to compromise the block. The power potencial of a solid roller far outweighs the small amount of extra stress on the block. Id be more worried about engine balance and extreme rpm than a hyd roller vs solid roller. Their are some really nice smaller solid roller cams that don't require race type spring pressures that will out perform any hyd roller. The only way to get the hyd roller to perform near as well is to use high spring pressures and short last the lifter -.005 preload which just turns a hyd roller into a solid roller. Thats nomally just done for class racing where you must run a stock style lifer and idiots that do it on a street car.

hillbilly pony

IM pretty sure mine are considered race type spring pressures...Mine are 1.95@223 and 1.33@601. Cam is .672/.672. It is a 1972 model block so ill keep my fingers crossed. i guess ill tell the machine guy to realy spend some time balancing it.