17" X 7.5" RIMS. FITMENT/OFFSET??

[sweet97]

I Have Found A Wheel That I Like At A Good Price. It's An American Racing "casino". I Would Like To Get The 17" X 7.5" For Size. For The 7.5" Wheels What Offset Would I Need So Nothing Rubs? I Have A '93 Awd Talon. What Width Tire Would Mount To These Wheels And Also Not Rub?
It Seems Like The Stock 6" Is Close To The Strut/spring Mounting Plate? I Tried Posting This Question On Buschurs Site But Guys Don't Know What Offset They Have If They Do Have Wider Rims.
This Club Has Many More Members So I Am Hoping Someone Will Be Able To Provide The Info I Need! I Was Hoping That A 245/40 Tire Would Fit And Have The Same Diameter As Stock So The Speedo Will Still Be Accurate, That Is A Must. Any Help?? Tanks, Mark
Ps: Excuse The Caps As It's Early And My Eyes Are Not Working Well This Soon After Waking!

 

[sweet97]

The owners manual says the stock offset is 46mm(1.81") and that is with a 6" wide rim. Aren't there any guys rnning 7.5" rims that know their offset? Mark

 

[jtmcinder]

When you post something that's almost unreadable and - when a reader claws through it - turns out to be a question that is asked several times per week, then don't expect answers, not here and not on Buschur's list ... at least, don't expect an answer that doesn't first rip you a new one for being lazy and sloppy.

The offset that you want for a 245/40 is +40mm. But I would not put a 245/40 on a 7.5" wheel; if you insist on this width wheel, then I'd back off to a 225/45. This would also allow you to up the offset as high as +45mm (as long as you don't get Azenis), so you don't have to roll the fender lip.

- Jtoby

ps. I know that this isn't NABR, but it also isn't a Honda list

 

[sweet97]

Thanks Jtoby. As far as the original post that I am responding to here I mistakenly used caps throughout and the system left the first letter of each word capped so the post looked sloppy for which I apologized in that original. I guess you did not accept my apology. As I learn more about a subject my questions evolve so I will post the new question. If it is more appropriate to stay with the original and just post the additional question I can do that. I am neither lazy or sloppy and you can feel free to simply not read any of my posts.
I read dozens of posts and responses trying to get info on offsets. As i understand it the larger offset puts the rim closer to the fender lip. Is that correct? Mark

 

[wret]

Just the oposite. More offset centers the tire more inboard towards the suspension. Less offset centers the tire more to the outside.

See these:
http://vfaq.com/FAQlocator-suspension.html
http://www.prostreetonline.com/pso/pages/techtips/showarticle.asp?articleid=9
http://www.dsmtuners.com/forums/showthread.php?postid=792976

 

[sweet97]

Wret you cleared things up with that info! I go back to big block cars of the 60's and positive offset was outboard as far as I and others of the day called it.
So since the stock 6" rim on my '93 is 46mm that means that 4.8" is inboard and 1.2" outboard. That's with 46mm equaling 1.8". Split the 6" in half and I get 3". Add the 46(1.8") to the inboard side and I get 4.8" inboard leaving the difference of 1.2" outboard.
Now I believe I can calculate what I need to fit the 7.5" rims so the ties will not rub!
I could probably fit 5" inboard leaving 2.5" outboard.
Halving 7.5" equals 3.75". To have 5" inboard I would need an offset of 1.25" or approx. 32mm offset!
I believe I will be able to tell if the offset of any wheel I look at now will allow me to calculate whether it will fit clearly. Thanks again Wret!

 

[wret]

Wret you cleared things up with that info! I go back to big block cars of the 60's and positive offset was outboard as far as I and others of the day called it.
So since the stock 6" rim on my '93 is 46mm that means that 4.8" is inboard and 1.2" outboard. That's with 46mm equaling 1.8". Split the 6" in half and I get 3". Add the 46(1.8") to the inboard side and I get 4.8" inboard leaving the difference of 1.2" outboard.
Now I believe I can calculate what I need to fit the 7.5" rims so the ties will not rub!
I could probably fit 5" inboard leaving 2.5" outboard.
Halving 7.5" equals 3.75". To have 5" inboard I would need an offset of 1.25" or approx. 32mm offset!
I believe I will be able to tell if the offset of any wheel I look at now will allow me to calculate whether it will fit clearly. Thanks again Wret!

No problem. Just remember, wheels are easy to fit. It's the tires that make it tricky.

 

[dont need 8]

The owners manual says the stock offset is 46mm(1.81") and that is with a 6" wide rim. Aren't there any guys rnning 7.5" rims that know their offset? Mark

I have 17x7.5 with a 42 offset. I am running 235/45 and they rub occasionally when I hit bumps while cornering. I guess I will have to go back to 225/45, but I like the added wheel protection that the 235/45s give me.

 

[sweet97]

Don't need 8 what about a 40 series 235? Are the 235/45's taller or shorter than stock or about the same? Don't need 8 do they rub fronts or rears/
Wret I can see with the stock 46 offset and the stock tires how they come close to the springs in the back so I think I will be able to make an educated guess since I got that formula from you. that's the kind of info I needed. The American Racing "casino" rims I like come in a 17" x 7.5" but I did not get the offset(s) availale. I want to go as wide as I can for the wheel width. As toby said 225's should work nicely. i would need at least an 8" to try 245's. Kumho ecsta super 712's are a good traction tire aren't they? and fairly priced. mark

 

[dont need 8]

To maintain the same overall diameter as stock the 45 series tire would be closest on a 17" rim, 18s would take 40, and 19s would use 35 series. The smaller the number the lower the profile.

With a 42 offset my 17x7.5 wheels and 235/45/R17 tires are right at the edge of the fender without sticking out. I too like the wider 7.5" wheels.

 

[sweet97]

I guess i'll be going with the 225's. I am coming off my ride being a Conquest that had 9" rears and 8" fronts. the Talon looks like a Saturn with these skinny wheel/tire combo!

 

[Silverspyder]

I have 17 x7.5 on my '92 with a +45 offset...I have 225's and no rubbing here!

 

[wret]

I have 17x7.5 with a 42 offset. I am running 235/45 and they rub occasionally when I hit bumps while cornering. I guess I will have to go back to 225/45, but I like the added wheel protection that the 235/45s give me.

I would have said 42mm offset was about the highest you could go with those wheels and tires WITHOUT rubbing. Apparenly your brand of tires is a little wider at the tread.

 

[sweet97]

Wret wouldn't that depend upon where his tires are rubbbing? He says when turning and hitting a bump at the same time. You think then a 36 offset would solve that problem with that size tire? I am going to get the offset of the wheels I like tomorrow so I can see what tire I could fit. A 225/45 should be no problem yet still give the car a more aggressive stance. Mark

 

[wret]

Wret wouldn't that depend upon where his tires are rubbbing? He says when turning and hitting a bump at the same time. You think then a 36 offset would solve that problem with that size tire? I am going to get the offset of the wheels I like tomorrow so I can see what tire I could fit. A 225/45 should be no problem yet still give the car a more aggressive stance. Mark

Okay. It seems like you're really interested so I will go into detail (most guys want "Will it fit? Will it fit?)

With dontneed8's wheel / tire combo, with a 42 mm offset, he has minimal clearance between the tire and the control arm. It's speculated that 4mm is required to allow for tire flex when cornering, although I don't think that's ever been tested. This is the most critical point of DSM wheel/tire fitment. To get more room, you subtract from the offset to place the wheel more to the outside (outboard if you prefer). It's better in general to keep things as far to the inside as possible. You may get accelerated bearing wear and weird steering characteristics as you go below 35 mm offset.

40 mm is a good choice for tires up to 235 width. With that setup you can still get the tire under your fenders (barely). And yes, 225's would fit easily.

Look at it this way, "dont need 8" has 235/45/17's with 42mm offset. In extreme driving conditions he is rubbing so he probably needs a couple more millimeters clearance. 40mm offset (or 2mm spacers) would fix that problem. So, you can consider 235/45/17 with 40mm offset a ZERO CLEARANCE SETUP. You can change conditions such as diameter, width, and offset but don't go less than ZERO.

If you look at tire dimensions using my favorite calculator: http://www.miata.net/garage/tirecalc.html, you will find that a 225/45/17 tire has a radius of 317mm and the 235/45/17 has a radius of 321. This difference gives you 4mm more clearance with the 225's. Add this to the 5mm decrease in width (of one half of the tire) and you now have a clearance of 9mm (plus the 4mm needed for tire flex).

Once you get to where you think you have the perfect sizes selected, look at specs for the tire brand and model you selected. You will find some variation between brands. I was pleasantly surprised to find 245/40/18's Azenis ST115 fit on my 40mm offset wheels without rubbing. 245/40/18’s of another brand might rub like a cat in heat.

**EDIT**
Just noticed that "dont need 8" is comparing 2g fitment with 1g. This is not necessarily a wise thing to do. The fitment issues are similar but I have never compared clearances of 1g and 2g models.

 

[sweet97]

I'm interested because I want to learn. That's why the guy near the beginning of this post gave me some grief because I sometimes reword a question to try to get info from guys who sometimes don't seem to know anyways! Or with some info learned I have a new question close to the first.
Man you're able to run 245's up front too and with 8" rims! Those 18" must make for a very low profile, does that create a hard ride? I will be looking into the wheel I like tomorrow and find out the offsets available. It's an American Racing and I think it's called "Casino". It has some of the older 5 spoke look I am used to but the spokes split into 2 each for 10. Partly polished, partly machined wit fine grooves and the rest clearcoated over silver/light grey powder coat.
I was thinking of the Kumho ecsta super 712's. Are those a sticky tire? Any suggestion for a good moderately priced tire? Thanks, mark

 

[wret]

That guy that gave you a hard time knows more about this stuff than most, but he has no patience for guys asking questions that have been asked over and over again. He also has no tolerance for people using oversize wheels over puny brakes. The 17's you are considering are fine. 18's like mine cross into the show column (rather than the GO column).

Yes, you can run 245's in front. No dsm that I know of uses larger tires in the rear. Yes 40 series are pretty low profile and I would not personally ever go with anything lower. It would just be too impractical for public roads. Yes, they are a little rough especially combined with a stiffer suspension. You shouldn't have to wory much with 45 series on 17" wheels.

Ecsta Supra 712's are the bottom end of performance tires. They are not particularly sticky but they are cheap. They have no treadwear warantee and they wear quickly. I've had a couple of sets. IMO, pay a little more and get a better tire.

 

[jtmcinder]

Yeah, "that guy" can be a bit of a jerk when one of his pet peeves appears, but I hear he's better this evening, given that the event that was making him nervous is over (and he put a 2-plus-second hurting on his rival, tee hee).

I agree that the 712 sucks. If you've got your stock rims to put some Blizzaks or Graspics on for the winter, then I argue for either 245/40/17 MXs or 225/45/17 Azenis, depending on how long you want them to last. The best offset for these on a 2G is +40mm; I've heard that this also works on a 1G, but I've never seen it in person, so I probably shouldn't have written that.

- Jtoby

ps. thanks, Ron; very kind

 

[dont need 8]

Just noticed that "dont need 8" is comparing 2g fitment with 1g. This is not necessarily a wise thing to do. The fitment issues are similar but I have never compared clearances of 1g and 2g models.

Sorry, I didn't notice he had a 1g. When I had 225s they didn't rub at all though.

 

[sweet97]

Well I ordered my wheels and tires today. I got American Racing "casino's" 17" x 7.5". 45mm offset. I'm going with kumho Ecsta Supra 712's. 225/45-17. They may not get the best mileage but they are sticky and they come with a "W" speed rating which I was told is the current highest rating. I thank everyone for their help with assisting in my decision. Mark "Sweet"