Excalibur;

I think your valve train is living due to the "relatively mild" cam you are running. I ran a bigger cam than yous in a 502 in my previous boat and had no issues in over 60 hrs. I think when your durations start getting into the 280's+ @.050 coupled with .750"+ lift, heavy springs and extended idleing periods a traditional solid roller lifter can't take that sort of abuse. Tell us some more about your engine, what is your compression, heads, induction, etc? What kind of power are you making? Are you a solid or hydralic roller?

I spent my money in the bottom in anticipation of putting a blower
on in the future.I started with a merlin raised cam 10.2 pro block.
Lunati 4340 crank,oliver 6.7 rods,weisco special made 4.5 pistons.
Compression is 8.8 to 1.Had a set of heavyly reworked LS-6
heads so i used them,lot of clearancing needed with the raised
cam for the push rods.Merlin marine dominator intake and 1050
dominator carb.Engine makes right around 700h.p. on pump gas.
Very happy this year with the engine.When i get enough drive i
would like to try a 14-71 blower.This engine sits in my 24'
Excalibur.

You do have a sweet bottom end. I'm running the exact same rods you are. I'm with you on adding the big "huffer" when there is a viable alternative to going the B-MAX route.

jdnca,

What kind of seat and over the nose spring pressures are you running with the Schubeck radius lifters now? Thanks

280# seat and about 785# opening. Erson E915170 springs.

JDNCAs springs are 280# @ 2.100 and 794# at 1.250. At .700 net lift he has around 700 lbs over the nose.