Fitting 18" wheels with 35mm offset

[DOHCTA]

Could you clarify this statement? Maybe I'm not interpreting it right, but I can think of a couple members running 235/40/18 on 18x8.5 +40mm wheels.

My rim size is 18x7.5" with a 34mm offset. The tires I'm installing today are 235/40/18. From what I've read, It's highly unrecommended to exceed the 7.5" wide rim with a 245mm wide tire. I'll snap pics of the rim's and tires later today.

245 tire is 10" wide. - 8.5" rim = 1.5" size difference
235 tire is 9.5" wide - 7.5" rim = 2" size difference

A 245 on a 7.5 will be just an extra half inch, but if you're getting a great deal on 235's go for it.

I am getting a great deal! Not that I'm made of money, but If I don't like these tires and the way these wheels ride, I'll sell them and find something a little more suitable for my use.


Thank you guys for your input. I appreciate the help as usual!

 

[jtmcinder]

235's can't exceed a 7.5" wide rim....from what I've heard and read on line.

Don't pass on total BS again, please. The "I've heard" or "read it online" defense will not work again for you.

A 235 is happiest on about a 9" wheel. Some 235s even prefer a 9.5" wheel. Note, however, the added weight for a wheel wider than 8.5" is probably not worth it. But the idea that you can't go wider than 7.5" is pure and utter nonsense.

 

[DOHCTA]

Don't pass on total BS again, please. The "I've heard" or "read it online" defense will not work again for you.

A 235 is happiest on about a 9" wheel. Some 235s even prefer a 9.5" wheel. Note, however, the added weight for a wheel wider than 8.5" is probably not worth it. But the idea that you can't go wider than 7.5" is pure and utter nonsense.

Ok there captain. If I can't turn to the internet or advice from a friend or a mechanic, where else would I get this type of VALID information?

I can't understand how you're a wiseman here but such an a$$hole..?

If you haven't noticed by now, I'm not thanking you for your help. Because, YOU'RE NO HELP! Unless this website gives kudos or rep points for being a DB.

18s on a car that doesn't need them because of the brakes is bad

IF this is the type of advice you give newer users learning about wheel and tire fitment, then I can't see why you even bothered posting a response to my question.

BRAKES??? WTF WHAT DOES MY WHEEL AND TIRE SIZE HAVE TO DO WITH MY BRAKES, other than clearing the calipers which obviously, an 18 inch rim wouldn't have any problems there???

I even gave you the courtesy of ignoring that comment until you lashed out at me. WOW!

 

[jtmcinder]

18" wheels have a higher rotational moment than smaller wheels. Therefore, they are harder to speed up and slow down. That's why, if you don't have to run 18s for some other reason, such as caliper clearance or the tires you need only come in 18s, you should not run 18" wheels. The small gain from the shorter sidewall (for a given total diameter) does not make up for the added rotational moment and the lower quality ride.

Note: in contrast, there's a lot to be said in favor of 17s over 16s on a DSM. Do not take my reason for arguing against 18s as meaning you want to go to the smallest wheel that fits over the brakes. Only drag-racers should do that. People who turn should stay with 17s, assuming street tires.

As to the issue of asking you to "please" not pass along incorrect information, such as the silly idea that a 235 can't be put on a wheel wider than 7.5", I will not do this politely again. Sorry about that. It was a moment of weakness on my part. I'll go back to my regular way of dealing with BS.

 

[DOHCTA]

so we're friends again?

 

[MrBoxx]

In addition to the reasons jtm mentioned, there are practical reasons to go with a 17" wheel as opposed to an 18" wheel. For one, the higher your sidewall, the more comfortable your ride is going to be. If you drive this car on the street for longer than 10 minute trips, you're not going to want to feel every line in the road, every pothole, every piece of gravel and rock that your low profile tires run over. In addition, regarding potholes, if you hit one, chances are good with an 18" wheel with a low-profile tire, you're going to have a greater chance of doing irreparable damage to your wheel. With a higher profile tire on a 17, you increase the chances of saving the wheel, even though you might sacrifice your tire, but at least you won't be replacing both of them. Which leads me to the third practical caution: Not a lot of tire stores carry performance-sized 18" tires. In the event of an emergency, you're more able to find a common 17" tire easier than you would an 18" tire, and in doing so, they tend to be cheaper.

Just more things to consider.

 

[EclipticalGS]

I use 255/35/18 gforce kdw 1s on a +40 offset, 7.5" rim with about 5mm clearance to that vertical knuckle bar front and rear. I ended up dremeling out another 3mm (clearance for hard cornering). Even before doing this I've had no rubbing even at full lock turning.

The faces on the workers watching this 10" bead to bead tire get forced onto the 7.5 rim was pretty funny.

 

[jtmcinder]

I use 255/35/18 gforce kdw 1s on a +40 offset, 7.5" rim with about 5mm clearance to that vertical knuckle bar front and rear. I ended up dremeling out another 3mm (clearance for hard cornering). Even before doing this I've had no rubbing even at full lock turning.

The faces on the workers watching this 10" bead to bead tire get forced onto the 7.5 rim was pretty funny.

Wait. You not only shoved 255s onto a 7.5" wheel but you also shaved (aka weakened) your front and rear knuckles for tires clearance?

Please PM me your SS#, DoB, and marital status. I'm taking a policy out on your tonight.

 

[EclipticalGS]

Wait. You not only shoved 255s onto a 7.5" wheel but you also shaved (aka weakened) your front and rear knuckles for tires clearance?

Please PM me your SS#, DoB, and marital status. I'm taking a policy out on your tonight.

Hehe wife beat you to that.

Of course being practical and all, the the thickness of the cast steel vertical bar in the area shaved was 27mm thick so a 3mm groove with about a 10mm radius is only 3mm depth at the deepest point and then exponentially returns back to 0. This was done along the vector at which my tire would roll into it around a very hard turn so it evenly reflects about the same radius the patch of tire that would "come close if ever". Lastly, the vertical bar is 27mm thick at the edges, it does however have a groove in it vertically (stock) which brings it down to about 23mm at its lowest thickness..Any problems that could occur have been error proofed by using a 2" long vertically, by 1/2" wide, and 3/16" thick plate heated up and bent to the radius of the vertical bar fits well inside the groove of the bar. Once welded in place directly behind the weakened area pretty much sealed the deal.

Currently in the middle of an AWD swap at a low tire pressure the meats will hook up nicely, already fwd with 40 psi in the tires my cornering has been very consisent and with the low profile added with the very tight fitting tire (side to side), it doesn't want to wash out on the rim. Lower the pressures and FWD launches @ 4500rpms were nice with light clutch feathering. My Chrysler 300 with 55/17s at 35 psi has noticable tire roll on the highway when accelerating out of turns and the dsm felt solid at much tighter turns with no visible rubbing even before the clearance added. That already tells me that my tire hasn't washed out enough to clear a 5mm gap that seems pretty rigid. Front suspension has about 3/4" clearance to fender, 1-1/4 in the rear, its set to -2* Camber, at full bump it sits a little over -3.5*.

So far I'm pleased with current setup.

 

[ZenkaiRacerDsM]

I need to bring this thread back to life.

I'm about to purchase a full set of 235/40/18's on my 7.5" wide rim with a 34mm offset. I hate tire shoping, but at the same time, need to learn more about our cars in terms of fitment and rubbing issues. And my car is riding on the Eibach Pro-Kit lowering it by 1.5 inches.

I realise there is a thread dedicated to a spreadsheet style explaination of "what wheels/tires fit my car" in the newbie forum but my SIZE isn't listed.

I got a great deal on the rims and I love the look and aggessive stance it gives the car, the current 215's are a little to narrow for my liking but I need to decide asap on whether or not I should go with 225's or 235's.

Help is appreciated.

DOHCTA

This is exactly what I'm running on my car minus the offset. I have the same springs as well. Mine are 42mm offset which should give me more fender clearance then you.

With that said my tires rub the rear fender lip. I would imagine with a lower offset the rubbing would be even worse.

It also depends on the brand of the tire too. I had some General Exclaims before the Federals I just got and the Generals cleared just fine. But by design the Federals are tiny bit wider and hit the rear fenders.

I do think the rear of my car sits abnormally low though for pro-kit springs. I would post a pic but am currently deployed.

Edit: Forgot to mention the rubbing only occurs over bumps.

 

[4WARND]

I picked up a set of Rota Grid Offroads, 16x8 with a 10mm offset. I ran them a bit last year with the Hoosiers and I had spacers on the front wheels. They seemed to fit fine. I did not have spacers on the back and once removed from the car I can see where they rubbed the drums slightly. I just ordered street tires for these wheels, Hankook RS-3's, 225/50/16. My plan is to add 10mm spacers to the rears and I think I should be fine? I will admit I am a total newb when it comes to wheel offsets! Any thoughts? I do have a DSS coilover kit on the car.

 

[jtmcinder]

If I'm reading your post correctly, with the spacers you will have a zero offset. That's just nuts.

But I can't be reading it correctly because it seems to say that the rear wheels rub on the drums.