$5000
Sorry, that was really mean....
It is a question that has often been asked and the answer is pretty simple:
A Jota has higher compression pistons, more aggressive camshafts (4C on a Jota, A11 on a 3CL) and a free flowing exhaust (nothing whatsoever in the "silencers" and a bigger bore collector). Oh, and a couple of Jota badges/decals. There are a couple of variants with bigger valves in a particular year, but not sure that was Jota only.
These days, so many 3CLs have become Jotas that I doubt it really matters about how they started out....unless someone is a collector or investor.
Hard to find new 3CL pistons these days, so most fit Jota CR pistons anyway. 4C cams are pretty brutal, F1 profile probably better (ask Keef). No-one sells 3CL exhausts, only Jota.
Pete
p.s.(oh, and I think the very early Jotas had a higher first gear, but everyone wants an orange one, so that doesn't seem to matter :

P
p.p.s. These smileys are pants :

(see, that one didn't work

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