Re: Solid roller valve train ?

88-406 · 01-19-2002, 11:16 PM

How long can one expect the springs,guides and seats to last with a somewhat radical solid roller cam? Are they tougher on parts than a Hyd? If you can get Hyd's to go 6500-7000RPM then why use a solid? Does engine life expectancy fall off sharply with 7500+ RPM?

Thanks

KM

danno85 · 01-20-2002, 12:59 AM

I don't know about the longevity of parts, although I'll be finding out
because I'm building an engine with a solid roller.

The biggest advantage to the solid roller vs. hyd. is that the opening
ramps can be "steeper". There are limitations to the hydraulic due to
keeping the plunger from collapsing (there is a technical term for this
but it escapes me), which is compounded by the fact that the hyd. lifter
is heavier (therefore more mass to move).

Anyway, I'm curious too about the life of valve guides, etc with strong
springs and occasional high rpm use - we'll see!

Dan

LPDesRoche · 01-20-2002, 01:21 AM

You can run a much more aggressive cam with a solid roller and still have a nice idle quality.

That and there aren't many hydraulic lifters that do their job properly above 6500. They just arent made for it.