It's not that the bottom end is weak...The problem is
that the oil galleries are too small to provide the
amount of oil that it really needs. The solution to
this is to open the oil galleries some more. This will
provide more oil to the mains (Especially the center
main...considering this is a 3 main engine). Pinning
the trust washers keeps them from falling out. Bring
up the compression, use a different cam, and put
either dual SU (HS4's), or a DCOE. Do not use a
downdraft Weber...that is, if you want performance.
Neck up the exhaust to 1 7/8' but no more than 2".
This will remove some of the back pressure. You could
lighten the flywheel as well. Most of all, you want to
align bore and balance the engine back to the
flywheel.
Dan Dwelley
(Very modified 1500 Midget)
--- Adrian Barnes <adrian@workgroup.net> wrote:
> Mark:
>
> Quite a few folks don't like the thought of tuning
> the 1500 motor, so
> there really isn't a whole lot of information out
> there about tuning it.
> I've never run across a book, for sure. The theory
> is that the bottom
> end is weak, so more power will cause it to spin a
> bearing or drop a
> thrust washer or something. A famous quote I hear
> regularly is "Ask the
> Spitfire people," because the motor really is from
> that car. You might
> find some info from them.
>
> Some "safe" modifications include boring the
> cylinders .020-.030 over,
> using high-compression pistons, changing the cam,
> using a header, or
> changing to a Weber DCOE carb. Some people like to
> pin the thrust
> washer in place, although I've never done that.
> Also, for a chunk of
> change, Front Line has a 5-speed conversion for the
> 1500.
>
> If you find any of those books, let me know!
>
> Adrian
=====
Dan Dwelley
77 Midget
64 Sprite (Rotary Project)
Alexandria, Va.
"The intuitive mind is a sacred gift and the rational mind is a faithful
servant. We have created a society that honors the servant and has forgotten
the gift."
- Albert Einstein.
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