In a message dated 1/28/00 7:59:12 PM Pacific Standard Time, gls@4link.net
writes:
> I'm confused. The Mallory dual point has mechanical advance and no vacuum
> mechanism. When you say you would not do away with the vacuum, do you mean
> that the mechanical advance is not as good as the vacuum?
>
> I haven't noticed any adverse effects. It doesn't ping under load or heat
> up. It performs much better than the stock distributor, which was
> undoubtedly worn out, so I won't use it as a comparison.
>
> While the HEI may have advantages at the 6,000 rpm range, I'm not likely to
> run my 235 anywhere near that, so isn't the advantage mostly theoretical?
>
> Not that I'm a purist (I've got a T-5 in mine too, but you can't see it),
> but there's something a bit incongruous about a '50s engine with a
'70s-'90s
> ignition.
>
> Regards,
>
> Grant S.
If I might chime in for a bit.
My feeling is the reason to go HEI is to eliminate points all together.
Better cold weather starting, and generally easier to maintain.
Mechanical advance has it's place, but usually in the hotrodding area,
vacuum advance adjust to engine load much better and keeps the timing more
optimum for better fuel economy.
Vacuum advance also has mechanical in it as well, vacuum advance usually
will get you to about 12-14*'s more advance over initial setting, then the
mechanical advance (springs and wieghts) will take over for total advance.
Mike
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