This subject turned up in another thread last week. It seems that some of the finer technical details which helped to give this engine it's worthwhile extra advantage in output over the standard 499cc engine are either very elusive or not widely known in any case. So as promised, here are few scans from a old "Glenn's" manual containing a few clues.

It would be really useful to some people and very informative for the rest of us if anyone else is able to share any other details that they know of.

Distributor....note the differences.

500 Distributor Specifications by Peter Thompson, on Flickr

See how it affects power output:

500-General Engine Specifications by Peter Thompson, on Flickr

Identifying by engine number:

500 Engine ID Numbers by Peter Thompson, on Flickr

Bear in mind, as the illustration shows, this is all for the USA model which may also have some differences in the engine departments....I can't be certain either way on that.

that's not a USA 500, it's a Bianchina....
I can't remember which model but many more were fitted with the 110.004 (Sport) engine than were fitted to 500s..
Interesting the numbers your book gives for the "sport" engine..
110.040 and 110.044 I have never encountered these numbers before...

Ohh and US Spec engines have all sorts of differences... the exhaust is a particular one.. wish I could find one ...

Bigvtwin996 said:

that's not a USA 500, it's a Bianchina....
.

Click to expand...

Splittin' 'airs again. ........a 500 dressed up in fancy American clothes.

Most of the mechnical gubbins seem to be the same as our familiar little bubble-car though.

fiat500 said:

Splittin' 'airs again. ........a 500 dressed up in fancy American clothes..

Click to expand...

Bianchina is Italian .. split split...
but yes if you rip off the panels it's a 500...
you could scan me a copy of that book... it looks very interesting.....

don't mention Necker or Sean will be here......

Bigvtwin996 said:

but yes if you rip off the panels it's a 500...
you could scan me a copy of that book... it looks very interesting.....

Click to expand...

If I ever get one I'm sure I'll have to rip off the panels anyway.....

"Bianchina".... milky-white?

When I have a quiet couple of hours I will scan the whole book. It's very interesting although it broadly deals with all the Fiats across the ranges, which would have been available at that time. It also clearly explains many of the principles which would answer most of the basic questions that ever get asked about on this Forum.

This is the spec I found deep in the Fiat workshop manual. I was surprised to see that the advance on the 500 Sport was less than the standard engine and at a much higher rev rate. So the sport distributor would have been specific to that engine.

Bigvtwin996 said:

Bianchina is Italian .. split split...
but yes if you rip off the panels it's a 500...
you could scan me a copy of that book... it looks very interesting.....

don't mention Necker or Sean will be here......

Click to expand...

Someone mention Necker?
Did I tell you that I foolishly passed on buying one of these. Not knowing what it was at the time....

Vague details but clues and the onvious items to upgrade:

"By the late ‘50s, the 500 saw success as a racer, taking first, second, third and fourth at the Hockenheim 12-Hour endurance race. To capitalize on this, Fiat offered a Sport model in 1958, which had a larger, 499 cc engine equipped with a new camshaft, valves, cylinder head and fuel system, boosting power to 21.5 horsepower."

https://www.topspeed.com/cars/fiat/1957-1975-fiat-500-ar170669.html