Evening all,
I have a set of (7Jx17 H2-41) OEM Speedline wheels from an early 2000s Stilo in the garage. Decent enough tyres if almost at the end of their 10yr life span, currently wrapped in 215/45r17 rubber
Aside from the obvious speedo mismatch which can be almost eliminated by dropping to a 35/40 section in the future what are the chances of them fitting and not rubbing anywhere as a straight replacement for the coupe OEM wheels (6,5Jx15 H2-40)...

also what is the H2 in the sizing? Never had to deal with non-oem wheels.

im presuming the 1mm difference in off set wont make a difference, but im guessing the 12-13mm differece in rim width along with the added tyre size may cause issues.
if so would i be looking at a 10mm spacer set? of so what kind of handling differences should i be aware of?

If you have the 20V turbo Brembo front brakes, you need to make sure they clear the calliper. I got a set of "Petal" 500 Abarth wheels. Width and offset seemed prefect, so I had them (expensively) restored, only to find they were far from clearing the callipers. The "spokes" in the original wheels arch or bulge outwards, to make room for the chunky callipers. Going to a larger diameter rim is no guarantee they will clear the brakes.

In the end I got a set of phone dial Alfa Romeo wheels, off of a Mito. They are _just_ touching the caliper, and that will easily be resolved with a 2-3 mm spacer.

The H I believe is to do with the shape of the wheel barrel and thus how rigid it might be. But to be fair not a variable that I've seen much.

Regarding fit. I'll bet they'll fit fine for a non turbo, but you could get some rub on full lock etc. Unfortunately only way to be sure is fit them and see. For example I've 18inch wheels on my turbo, but with a 35 profile tyre. Over the years some tyres would rub when new and others not. The speedo was also constantly accurate to GPS at road speeds so I would wouldn't worry too much about throwing the speedo out, but just remember you could lose the tolerance

ill suck it and see when i finally get the fronts built up.

Thank you both for advice @Mags i'm running the standard OEM ATE? front calipers, but it will be on Brembo rotors and discs (not that it makes a difference in this particular case)
@szkom, thanks. more googling required to find H2

Rim Cross Section Shape.

https://www.tyreleader.co.uk/tyres-advices/wheel-markings

Now we know! not a million miles off with rigidity, cross section will definitely aid with rigidity