Is there a rule on tire Tire / Wheel width? (Page 1 of 2)

Nothing's stopping you. But usually there are other elements of the car required to make those tires effective...

Control F works fine in on the Rules page.
https://24hoursoflemons.com/prices-rules/

But no, there is no rule against tire size. Only Tread-wear rating. (190 or higher) On DOT tires.

I'm not sure what you think a 275mm Tire is going to do for you, but by all means have at it.

Some people really like Understeer.

Also, they will need to be covered by fenders.

The only rule is that they need to fit within the fenders:

3.J.2 Fenders, Doors, and Hoods Required. All cars must have fenders at all wheels so that no tire surface extends past the body; all doors in place; and OE hoods. Hoods must be securely mounted by OE hardware and/or strong fasteners at all corners.

You don't need a search function.  The rules are quite short.  You really need to read the entire set of rules before you start your build.

bs

You can add to the fender to cover a wider tire.  Many teams have very inventive ideas on how this is done and what materials to use.
But as stated a number of times putting a "really wide" tire on a car won't make it faster or more reliable. That last item is the most important thing you need to try to attain when racing in Lemons.

Bearings love more grip...

I love fat tired cars.  Please, go 305.

One good thing about wider tires: they usually last longer.  Notice I said usually.

I don't know...i think we scared em off the forum.

Stefan2057: none of us are funding your build or doing the work, so you do you.  We're all bench racers when we're on this forum (albeit, some here have an immense amount of knowledge on and off the track) so take some, all, or none of the advice. 

Just go out and have fun.  If you break, fix it until you can't anymore.  There will be plenty of help at the track, and there's plenty more here too.

FYI expensive lightweight BBS/Enkei/Ronal racing wheels are NOT budget exempt.

Your car came with rims, so if you show up with something forged, fat, and fancy, you will get scrutiny and likely laps

I stand corrected- lame. didn't use to be this way. get off my lawn.

Isn't this an issue with BMW E30s who fit wider tires? They end up eating wheel bearings

Strictly speaking, this is true. Wheels and tires are budget exempt.

HOWEVER, pretty much no one who's ever rolled up on 275s has left any other part of their car alone. So big tires and expensive wheels—like budget-exempt enormous brakes—on a new Lemons car will invite a closer look at the car.

As pointed out, enormous tires don't seem to make road racing any easier and most teams that put on fat rubber and pack the car full of cheat haven't actually figured out the nuts and bolts of endurance racing to where they actually win. YMMV.

Ultimately, run big tires if you want, just make sure you have enough fender to cover them.

The best big-tire Lemons car of all time was the Bad Decisions Mercedes that had a Big-Block Chrysler mounted in the passenger seat. It never hella worked long enough to find out if 305s actually made it "better," but if that's the kind of build you're going for, by all means, please do that: