Offset piston-pins (was: Re: 1750 rebuild

["John Hertzman" <johnhertzman@domain.elided>]

In the current 1750 engine thread  (Steve Thompson, Fred Zimmermann, Peter
Lundquist, Kevin Trent) I was interested to read Kevin Trent's remark that
late 1750s had offset wristpins (like the 2000) while early did not; I do not
remember having heard that before. The parts books do have different pistons
on early and late cars, as well as different ones on Euro and USA cars. The
break numbers do not parse perfectly with Fusi's numbers, some falling in 1970
and some in 1971, probably a Fusi data error. Kevin's early engine, with
rerung early pistons, he found relatively gutless compared to the 2000; Peter
Lundquist's early engine had been well tweaked with new, higher C.R. pistons
by Merrit Carden; Fred Zimmermann mentions nothing about the pistons in his
exemplary early engine.

I am interested because I owned concurrently a new late 1971 GTV and a new
early 2000 Berlina purchased a few months apart. While I never dragged the two
against each other my recollection is that the 2000 may have had more grunt
but the 1750 was definitely more delightful to experience. Subjective
impressions can't be quantified; I may be fortunate in not wanting to compete,
not caring about tenths of seconds, simply enjoying something else more. My
subjective response could also have been affected by my opinions on the formal
aspects of the two cars, particularly the grills and the dashboards, where the
1750s, both coupes and sedans, are the clear winners (for me; YMMV). I don't
think coupes-vs-sedans was a factor; I would lump my prior 1600 cc Giulia
Super, which was hardly a pretty face, with my 1750 GT Veloce as a more
enjoyable car, engine, and driver's environment than my 2000 Berlina.

The US parts-supply catalogs I have all list just one 9.5 CR piston set for
the 1750. I assume they and all other 1750 replacement pistons have the offset
pins- more than two thirds of the 1779 cc engines were produced for 116 cars
after the "1750" went out of production, and the late 1971 change was
presumably maintained as the standard for the following quarter century, and
there are probably very few pre-1971 1750s running now with their original
pistons.

KCT ended with "there is no substitute for cubic centimeters". For some
purposes, certainly. For others- well, maybe. No argument.

Enjoy yours,

John H.
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