The Original 355 took a hit....

[Bruce Plecan]

Same Cross Fire Base.  But, the last few thousand miles the CCC Carb.
We're dicussing, doing the TBI switch while apart.
Still amazing how with the carb just in the center how even the distribution
is.
Bruce

> Where you still running the x-fire or what?
> Kevin R

> > The 355 that I wrote about in tuning tips, and used for lots of 747
info.,
> > finally had it's first internal problem.   Well over 100 1/4m passes,
and
> > too many 600' passes to even guess at.   Now at about 70K miles, it's
> blown
> > a headgasket.  Happened on a really cold night, and the stations are
known
> > for adding lots of alky during the cold season, so I'd be easily talked
> into
> > it being not a real tuning problem, per se.   It microscopicly (?) blew
> the
> > fire band over maybe .020" near a water passage hole (rear side of #7).
> My
> > best guess is that there was a tank or two of heavily alkied fuel, and
was
> > just enough trace detonation that it silently lifted the head.   We've
had
> > enough single digit temps., that I just should have taken an addition 2
> > degrees of timing due to the weather <sigh>.....
> >   Just to summarize, this was a Comp Cammed, 9.5:1 AL vett headed SBC.
> >   At this stage the hone pattern is fully intact,  the pistons still
have
> > there crisp corners at the perimeters, no incidation of any valve
burning,
> > no large amounts of Carbon,  in general the wear is typical of a 10K old
> > stock engine.
> >
> > While apart, for the gasket change, going to clean the chambers (smooth
> > them, to avoid any machining edges), do a little pocket porting, and
> freshen
> > the valve job..
> > As much as a success this engine has been, just can't help to entertain
> the
> > idea of surfacing the heads, and tweaking it up a little more in HP.
> > While not a screamer HP wise, it's spent alot more time at WOT then most
> any
> > other street motor that I can imagine.
> >
> > Course, there are some ecm options, for things to do <g>.
> >
> > Course being the President of CSH, I'm also a customer.
> > Bruce

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