RE: Motronic Pistons

["Brian Shorey" <bshorey@domain.elided>]

> Excellent question, I'm surprised that no one has posted a response on the
> digest to this seemingly relevant topic.  I too will be rebuilding at
least
> one 2L this summer, and I am strongly considering the 10.0 Motronic piston
> & liners.   My concern and questions to the Digest are these:  Will the
> compression jump from 9.0 to 10.0 CR create a need to use the top octane
> gas?  Will I notice a significant increase in predetonation? The Spica
> injection already runs more lean than Webers, and will this accentuate any
> predetonation problems?   My Sperry head has been milled and is no longer
> stock height and I use an 11mm cam - any valve clearance issues?

I'm not an expert engine builder by any stretch of the imagination, but my
understanding is that the Motronic pistons are *the* pistons to use in a
rebuild.  More efficient than stock, and better power than the 10.4 high
compression pistons (due to a better dome shape, or something like that..).

I know people who use them in Spica motors with no ill effects.

Can't say if a milled head will cause problems without knowing how much it's
been milled.  My guess is that unless it's been radically milled, it
shouldn't present a problem.

Ymmv,

bs

--
to be removed from alfa, see /bin/digest-subs.cgi
or email "unsubscribe alfa" to majordomo@domain.elided