small diameter HEI, was: 90/91 Vette distributor

[Tom Sharpe]

One more thought... My E.ProFlow uses a modified small or large cap HEI (mine
is large) with the guts replaced and the mechanical (and vacuum) advance locked
out. Normally the rotor advances with the mechanical weights to keep the rotor
in phase with the cap. with 45 degrees advance, the effective movement of the
rotor tip is 1/2 the distance to the next cylinder, possibly causing missfire
at cruse but not necessarily at WOT. Look at the marks on the cap and rotor..
if the erosion is on the end(s) of the rotor, maybe you need a wider rotor....
I silver sodered brass stock to the rotor to make the tip wider to keep it in
register with the plug wire at 45+ degrees advance. No more missfire.   Tom S

rr wrote:

> It all has to do with startup spark, coolant comp spark
> and lots of timing for light cruise. With a max of 42 deg
> allowed by the software, and six more by the inital, for
> a total of 48 deg, it cuts out...
>
> I've since reduced the max allowed to (42 - 6 = ) 36 degrees,
> and all is well.
>
> BobR.
>
> Shannen Durphey wrote:
> >
> > rr wrote:
> > >
> > > I'm running a small cap now, no firewall clearance. Am trying to figure
> > > out whether a large cap buys me anything. As far as being able to run
> > > more advance. I'm thinking that maybe an alum headed vette may be
> > > different, needing more timing and all.
> > >
> > > BobR.
> > >
> > Any pros to advancing base timing?  At least for testing purposes, you
> > could use it to determine max advance.  Why are you looking for more
> > advance?  No knock at present settings?
> > Shannen