new cams or regrind?

[oldchieft]

Hi all.
Has anyone got an opinion on cam shafts? The is an overpriced set of Piper 270's on eBay.

They are re-grinds, my instinct is not to use regrinds if new are available, but new are more then twice the price.

Has anyone any good information on regrinds v new?

Jon the Chief.

[rgh0]

I don't believe there is inherently anything wrong with a regrind providing it has been made well and the profile can actually be gotten out of the original cam without ending up with an unsuitable base circle size for the valve set up you are using.

The modern high lift shorter duration profiles generally need to come out of a new blank. The alternative is to build up the used cam with spray welding and then grind it back but that costs about the same as a new blank.

cheers
Rohan

[StressCraxx]

Rohan is correct, though I would be very concerned about spray welding to build up the surfaces.

I have had both very good and very poor luck with spray welding in an industrial environment. Surface prep and operator technique are vital for a good result. A bad result will make quite a mess.

An additional issue is the matter of shims. With regrinds, you may need to use extra thick shims because of the resulting smaller base circle. I have reground sprint cams in my Elan. My shims vary from 0.122 to 0.131".

Regards,
Dan Wise