Widest 16" Front wheel and tire combo

[Cowet]

Hi I've been doing some research into what the widest front tire and wheel combo I can get up front with 16" wheels. I'm intending on having a square tire set up as I'm looking to set this car up to handle. This is for a 1970 Dart with 73+ disc brakes.

I'll definitely measure prior to proceeding with anything and will validate backspacing.

Does anyone know if it would be feasible to run 16x8 wheel with 225/55/16 tires up front? Ideally I'd like to run 245mm width tires but I've seen conflicting info on whether this would work. I've noticed lots of people run tires that are far greater in diameter (27") than the factory tire size but I'm not entirely sure why other than possibly highway cruising. I imagine the correct diameter would help fender clearancing a bit.

Do 16 inch wheels have any clearance benefits over 15? Are 18" wheels the only diameter that assists in clearance? I'd prefer 16" wheels since I'm not a fan of low profile tires, but it seems like it's the only way to go to put tires wider than 225 in the front. Good tire compounds are a must which is why I'm not considering 15" tires/wheels.



I should mention that this car will be primarily used for fun and not competitive racing. Light autocross use would be fun.

 

[72bluNblu]

16" wheels don't buy you much for clearance on the brakes and suspension compared to 15's.

The issue with 245's is that up front to run 245's on 8" wide wheels you need a minimum of a 5" backspace. And really, a little more is better, say 5.25" to be sure. With 15's the absolute maximum backspace before you hit the balljoints is about 4.75", most have issues before that even. Once you go past 4.5" of backspace on a 15" rim it's kind of a crap shoot. 16's do get you a little more room, but with most rims that still means less than 5" and some might not get that much. So it's still hard to get enough backspace to get 245's to clear the fenders even with 16's.

A 16x8 with 225/55/16's should work, assuming you can find one with at least 4.5" of backspace and preferably more like 4.75". With tires wider than that you want to avoid going more than 26" in height, that whole 27" tall tire can work with skinnies and enough backspace but with anything 225 or wider it's really difficult to get them to clear the lower front corner of the fender when turning. I was actually kinda surprised to see there are some decent street tires in 16" now, for a long time it was far worse than 15" tire selection which is already bad.

For clearance, the big benefits start at 17". Most 17" rims can go up to about 5.6" of backspace before the clearance to the outer tie rod end becomes an issue. With 5.25 to 5.6" of backspace on a 17x8 you can actually clear a 255/45/17 up front on a Dart, although that's a 26" tall tire so the lower corner will be easier to deal with if you're closer to 5.6" of backspace. A 255/45/17 is also about the widest tire you can run on a Dart with the stock spring locations in the back too. Some cars would need a quarter lip trim to pull it off, a 245 is probably the last relatively "safe" width for a Dart with the stock spring locations without having your cars exact measurements. But for 17" you could run 17x8's with 5.25" of backspace with 245/45/17's all the way around if you have a BBP 8 3/4 rear. Some cars might need a thin spacer out back but some wouldn't, especially if you go rear disk brakes. 17's also get you some pretty decent tire compound availability as well.

18's clear the outer tie rod ends, and that opens up the possibility of 275's up front. I have 275/35/18's on my Demon clone with 18x9's. You can run the ~6" of backspace needed to clear those tires with the 18" rims. On a Dart though you can't run 275's out back unless you do at least a 1/2" spring offset in the back. More than likely that would also take a small quarter lip trim too. But if you did that, you could run 18x9's or 18x9.5's on all 4 with 275/35/18's. Possibly even on 18x10's, but that gets kinda sketchy for clearance and 275's on a Dart work better with a little squeeze because of the width. Depends on what you're willing to do to your fenders. I know member Tomswheels had 18x10's with 285's on his Valiant up front, but he also pushed the fenders out heavily and rolled the lips completely flat.

 

[dano]

I'll add tire selection in 17" is far greater than 15 and 16". Skip 16 and go to 17/18.