Wear?
Tom, re your additional power concern regrding the crank flexing. I kinda have my doubts about the crank flex at the HP we are using which is around 20 on the hi side with the direct drives in cruise mode at around 19/2100 RPM's. I have seen crank flex and twist as you probably know in a hi output engine. However I would give serious consideration to to much timing due to the setting methods and a lot of inexperienced mechanics. I'm not talking about detonation but a bit to much lead causing a minor shock when the fuel is lit. I have seen many many bearing sets with excessive wear at the bottom center of the bearing due to this. You probably saw many engines that felt spunky because of to much lead when it was actually running rough due to a bit to much when the engine was maxed out at WOT.
RE more power I'm pretty much dreamin here. I do feel we could gain a bit of torque and a bit of power with a profile ground fo 2500 RPM instead of 3500 RPM. Im' sure you have seen many an engine with to much cam for what was being asked of the engine. I'm talking 3~4 more HP at the same cruising RPM's. There have been many gains in profiles since the 20's when these beasties were developed. Like I said though I'm dreaminon this subject.
If I ever wind up rebuilding mine and the cam needs regrinding I would seek a different profile and try it. Isky has done many a truck cam for me over the years and if they or someone else had someting available it may be a minor improvement.
Dave Neptune
Tom, re your additional power concern regrding the crank flexing. I kinda have my doubts about the crank flex at the HP we are using which is around 20 on the hi side with the direct drives in cruise mode at around 19/2100 RPM's. I have seen crank flex and twist as you probably know in a hi output engine. However I would give serious consideration to to much timing due to the setting methods and a lot of inexperienced mechanics. I'm not talking about detonation but a bit to much lead causing a minor shock when the fuel is lit. I have seen many many bearing sets with excessive wear at the bottom center of the bearing due to this. You probably saw many engines that felt spunky because of to much lead when it was actually running rough due to a bit to much when the engine was maxed out at WOT.
RE more power I'm pretty much dreamin here. I do feel we could gain a bit of torque and a bit of power with a profile ground fo 2500 RPM instead of 3500 RPM. Im' sure you have seen many an engine with to much cam for what was being asked of the engine. I'm talking 3~4 more HP at the same cruising RPM's. There have been many gains in profiles since the 20's when these beasties were developed. Like I said though I'm dreaminon this subject.
If I ever wind up rebuilding mine and the cam needs regrinding I would seek a different profile and try it. Isky has done many a truck cam for me over the years and if they or someone else had someting available it may be a minor improvement.
Dave Neptune
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