Solid roller duration vs hyd roller duration.
#1
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From: NW Michigan
I realize there is a 6-8 deg duration difference btw Solid and hyd but how does this occur to get same seat to seat duration?
What gets me the most is the solid rollers with compatible numbers as hydraulic seem to have same peak rpm. Is this cause there's no give in the lifter and it's just taken into consideration or what. Just wondering what the real truth t o this is.
I realize solid rollers have more aggressive lobes and lose lift due to the lash but an advertised duration is advertised duration.
Just something that is a known fact by many but do many understsnd why this is. So then where does this put you when you throw solid rollers on a hyd roller cam. Duration somewhere in btwn??? Maybe MT touched on this a little in other thread but didn't cover this actual question.
Also if it's just at .050 where the diff is at it makes sense to the the more aggressive lobe with quicker ramp on solid. Is the entire duration 6 to 8 diff. I've never really put a lot of thought into this but if someone can explain in a sentence or two it will only help myself and others who are challenged with all this.
What gets me the most is the solid rollers with compatible numbers as hydraulic seem to have same peak rpm. Is this cause there's no give in the lifter and it's just taken into consideration or what. Just wondering what the real truth t o this is.
I realize solid rollers have more aggressive lobes and lose lift due to the lash but an advertised duration is advertised duration.
Just something that is a known fact by many but do many understsnd why this is. So then where does this put you when you throw solid rollers on a hyd roller cam. Duration somewhere in btwn??? Maybe MT touched on this a little in other thread but didn't cover this actual question.
Also if it's just at .050 where the diff is at it makes sense to the the more aggressive lobe with quicker ramp on solid. Is the entire duration 6 to 8 diff. I've never really put a lot of thought into this but if someone can explain in a sentence or two it will only help myself and others who are challenged with all this.
#2
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From: Michigan
So a solid roller cam's advertised duration is at the advertised lash(I would assume) so if you tighten up the lash would the engine 'SEE" slightly more duration due to less crank rotation before the valve begins to move? I assume so, but you can't effectively do the same with a hyd
#3
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From: NW Michigan
So a solid roller cam's advertised duration is at the advertised lash(I would assume) so if you tighten up the lash would the engine 'SEE" slightly more duration due to less crank rotation before the valve begins to move? I assume so, but you can't effectively do the same with a hyd
In actuality if you took the lash out of the SR and had same lift and duration as a HR you'd think it would be overwhwlming. No give what so ever in lifter so you'd always be getting actual adv numbers.
I hear what your saying but just still unclear on some peak rpm power. SR shows less duration yet pulls higher. Is it the lobe or the lifter? Kinda difficult for me to get out what I'm trying to ask so that's not helping either I'm sure. Lol
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From: NW Michigan



