TechArt rubbing issues!

Hey, I'm having some rubbing issues with my 295/35 ZR18 Michelin Pilot sports mounted on my rear TechArt 10,5" rims, I think the guy before me bought the wrong offset wheels or something.. Plus the Michelin Pilot Sport seems to have some sort of a outer lip that protects the rim and that makes it look a bit ugly and also adds even more to the rubbing issue.. I'm ordering new rear tires today and I wanted to see if anyone have some input on this issue? I was thinking of going with 295/30, that makes the tire 2.8cm lower (1.4cm upwards of course), that should be enough to solve the problem right? Or do I need to go down to 285/30 instead since the wheels sticks out a bit? My car is a Carrera 4 -04 with the X74 package! Thanks again guys!

bump Anyone?

Seriously? Cool your jets. People will respond if you let them. But bumping a thread wanting instant gratification will more than likely keep you from getting any input. 2.5 hours is not very long especially during the peak of the work day.

His anxiousness belies his screen name, don�t you think?

Sorry, I'm about to order them online ASAP that's why I'm rushing... I think I have the more aggresive offset, don't you think? Anyone? PS. I'm from Sweden, here it is night DS.

Before you order, it would help if you could supply us with a little more info. Where is the tire rubbing, inside or outside? If the offset on the wheels is wrong, then dropping down a size or two may (or may not) fix the problem. Do you know the offset on 10.5" TechArt wheels? I am not that familiar with the C4. Is it a "wide body" like the C4S?

Tim, It is a narrowbody C4, same as yours, I've taken pics now, how do I attach them?

Pics...

Now help me!!

Sorry but those wheels are the WRONG offset. Getting narrow tires is NOT going to fix it. Those wheels look like they belong on a wide body.

Sorry for the delay, but I had to stop and eat. Ok - Your offsets are way wrong! Just looking at your pics I am "estimating" that the rim of the wheel is protruding about 1/2" (or more) outside the lip of your fender. Dropping down in tire size will not help much, because the wheel will still protrude and so will the tire. There was another thread here l(ink below) recently where someone bought some new wheels and the rear offset number was too low for his car. He dropped down in tire size and now he thinks the tires look "stretched." The rim of the wheel extends beyond the tire (See post #56, top right pic). I suggest you read the entire thread because I think you are in the same situation as a couple of guys in the thread. https://rennlist.com/forums/996-forum/256724-upgraded-to-19-s-thanks-tim-question-though.html I am not certain how much you know about wheel offset, but I'll give you some links and a little info to help. If you already know all of this stuff, then I apologize. First, here is an offset calculator. http://www.1010tires.com/WheelOffsetCalculator.asp Below is the info I wrote in post #33 of the first link. Since I don't know the exact offset for your rear wheels, the example below assumes 52mm. On the Offset Calculator site, set the current at 10" width and 65 mm offset (OEM for most narrow body 996's). Then the new size at 10" width (I know, you have 10.5", that is the next step) and 52 mm offset.. You will see the additional "gain" on the face (outside) of the wheel is 13 mm. Now change the new rim width to 10.5" and keep the 52mm. Now the additional "gain" on the face (outside) of the wheel is 19 mm. Half of the additional 1/2" moves to the outside, compounding the reduction in the offset from 65 to 52. FYI, 26.1mm = 1", so 19mm is about 3/4" or so. Ultimately, you are going to have to find out the exact offset on your current wheels. The bottom line is that if you want to fix this long term and correctly, you are going to have to get new rear wheels. Either get 10.5" wheels with MORE offset than your current wheels (probably not less than 58mm) or get 10" wheels with 65mm (or 58mm minimum). I hope this helps. Reply here or PM me if you have any questions. BTW, what's your first name?

Tim, Thanks for your excellent post and all your help! I must have the TechArt 10,5 18"s with the 42mm offset that's listed in their parts catalog found at www.cecwheels.com The pics I showed you fools the eye a bit, the Michelin 295/35 looks like a damn ballon tire IRL, my car is lowered with the X74 and hardly rubs at all when I'm alone in the car, I'm almost fully convinced that going from a 295/35 to a 285/30 (it makes the tire height go from 663mm to 635mm, that's 1,4cm up and 1,4cm down of more space!) will solve the problem once and for all, at least I pray it does, I don't want any more headaches Arling from Lucent Motor told me that a 285/30 and some more negative camber should fix it easily. They've done it to several cars he stated.. What do you think? Once again, thanks!

LVDell, I think it's wrong of you to say it is the wrong rim since it is offered and recommended by TechArt for the 996 C4 narrowbody, also, it is way to small for a Turbo/GT2 since that car is wider and would need a giant 20mm spacer at least to make them look halfgood.. Thanks anyway for your time though, even though you often are a bit negative in your posts

Now I'm really sad and officialy screwed, just went out to the garage to take a final look before ordering my 285/30's thinking they will be much better than my 295/35's.. WRONG! I allready have the 30's Now what? Can I machine of some of the rim? Will going to 285/30 help? The Michelin has such a "fat lip" protecting the rim, looks ugly to, my previous Yokohama AVS Sports had flush tire sides, so does almost any other tire except the Pilot Sports, maybe this adds to the problem? Is there any danger to having one brand up front and another at rear? Damn TechArt for making one offset tooo agressive and one tooo girly Please, help?

This may help. I am not sure how much metal is on the inside of those wheels but you may be able to get them machined . The offset is way way too much, and I don't think there is enough metal to get what you need. I would offer to buy them but the offset is wrong! Too bad those would go nicely in my collection.

Slowpoke - 42mm offset? WOW! That's your problem. I agree with Paul (kilrgt) and would NOT attempt to machine the inside of the wheel. I would be concerned about structural integrity. As for a different tire on the rear, Porsche recommends keeping the same type of tire on both the front annd the rear. I could not find the "girly" offset you referred to in your post. What was the "girly" offset. You may be better of getting the "girly" offset and adding some spacers, or drop down to a 10" wheel. I have run out of alternatives. Sorry!

There you go again being the Rennlist police. Nice!

And there you go just confirming what most already know.......loving to just post without anything of worth. So answer me this.....do you agree that his bump was appropriate after 2 hours? Didn't think so.

Actually if you just look at the picture you posted you would understand why what I (and Tim) have said is that your wheel is NOT the proper size for your car. So, no, it is NOT wrong to say that is the wrong rim. And you really need to understand a bit about wheels before you start posting incorrect info. If you did, you would know that "at least" a 20mm spacer on that wheel you just offered in your pic would stick out on the wide body! As for your statement about being negative I wil say that you apparently know NOTHING of the input, help, and feedback I give to those that ask for it on this board. Just becasue you can't get your question answered IMMEDIATELY and you feel the need to bump a thread that WILL get answered at some point just proves my point.......you were called out and told to chill to which didn't sit well with you. If you have a question....post a thread...and sit back and wait for HELP. And if it doesn't come immediately don't DEMAND help. That is the quickest way to keep yourself from receiveing it.

Actually Dell is right. OK... Here's what I was told about that size offset it's for a Boxster and TechArt did use big *** spacers for the Widebody. I should know I HAVE a set, I think they are 15mm, BTW... does anybody need a set? The story goes something like this, TechArt made that rim 42mm for a Boxster, than made the C2 offset cast, but when it came to the Widebodies, they didn't want to spend the bread for a new offset cast, so... they used a spacer.

It was a joke, hence the damn smily face rolling around... uh. On a serious note, where's the hostility coming from? Knowledge? Being part of a online forum for a longer period of time or just posting more insightful information? It's nice that you speak on behalf of everyone here, I had no idea I wasn't saying anything of worth, wow. Was your second question rhetorical? The answer (not that you apparently care) is who cares if he bumps. Why's it bother you so much? Just answer his question with the wealth of knowledge you obviously have and be on your way. I think you're the one that needs to "chill".

Why are you thinking of maching them? Why not sell them and buy the CORRECT wheel for your car?

Thanks again for your reply! As I said, there are people running with theese wheels allready on their narrowbody cars so I will NOT sell the rims (who want to but 2 rear rims anyway?) and getting new ones! TechArt make stheese rims for a reason, the 60mm "girly" offset is no option since I don't want to ride with spacers, they only come in 8,5 or 10,5 so 10" wide is not an option neither. About the different tire thing, I know it is important since it a 4x4 car, but still, the sizes of the tires is not the same so does it really matter if the brand is? I think machining of 3-5mm of the rim and going to a 285/30 should solve this problem easily! Or else I'm going What do you think Tim?

I don't need to look at the pics, I have had cars 10x more extreme than my Porsche, I know that this wheel will work on the 996 with some MINOR mods, maybe tires alone will do it! My friend has a Turbo and he runs the same offset but 11,5" so NO, they will not stick out! Other than that, thanks for your time!

EricDee, I replied to ypur post on 6speed but again, What tires/mods/rolling do you have on your car? Please please take some pics of it? Thank you again!

Slowpoke - Here is my take on the whole situation. 1. Your car is a C4 �narrow body� 2. Your car is lowered with the X74 suspension 3. Your rear wheels are 18� x 10.5� with 42mm offset 4. Your rear tires rub on the fender 5. You want to maintain a wider, more aggressive look OEM rear wheels are 18� x 10� with 65mm offset, which is what I currently have on my car. Your wheels will protrude 29mm MORE than my OEM wheels. I dropped a �plumb line� from the outside edge of the rear fender and measured the distance between the �plumb line� to the wheel rim at the top of the wheel. That measurement was 18mm. If I added a 17mm spacer, the rim of the rear wheels would still be 1mm INSIDE of the lip of the fender. If I installed your 10.5� wheels (with the 42mm offset) on my car (with no spacers), the rim of the rear wheels would extend 11mm BEYOND the lip of the fender. The 18� x 10.5� with 60mm offset wheels are the correct wheels for a �narrow body� P-car. If I installed those 10.5� wheels (with the 60mm offset) on my car (with no spacers), the rim of the rear wheels would extend 11mm MORE than the OEM wheels, but would still be 7mm INSIDE the lip of the fender. If I added a 5mm spacer, the rim of the rear wheels would still be 2mm INSIDE of the lip of the fender. There are two other things to consider 1) the tire bead or �lip� that protrudes to protect the rim (indicated by the yellow in the attached pic) and, 2) the rolled fender lip, which extends inside the fender well (indicated by the red in the attached pic). As near as I could measure it, the bead on my tires is 3mm to 4mm. So the tire extends 3mm to 4mm beyond the rim of the wheel. Because it is slanted, the fender lip was more difficult to measure, but the lip is in the 20mm to 22mm range. That lip extends INSIDE the fender well and I took the measurements noted above from the OUTSIDE of the fender. This, of course, reduces the clearance for the tire by about 20mm. Ultimately, as I see it, you have three options: Option 1 � You can drop down a tire size and set more negative camber, but, in my opinion, you sill run a strong possibility of having your tires rub. Option 2 � You could try to �roll� the inner lip of the rear fenders. The rolled fender lips, combined with Option 1, MAY resolve the tire rubbing issue. Option 3 � You could try to sell your current 42mm offset wheels and get some 60mm offset wheels to replace them. If I were in your shoes, I would do Option 3 and get the correct wheel offset for the �narrow body� P-car. However, it is not my car and it is not my money so maybe that is easier said than done. Options 1 & 2 are just that� �options.� I am only throwing out other potential solutions and I do not guarantee that they will work. Whatever you choose to do is, ultimately, your choice and your decision. I hope you get this resolved to your satisfaction. Good luck!

Yeah, i was one of the guys on an older post that had an issue with the tire/wheel combo. In my case, 19". Not saying right or wrong, just posting a couple pics to show the difference between the michelin 295/30's to 275/30's. After further research from reputable tire resources, michelins are just taller and more oversized than industry standards. The first image shows how the car looks on 275's, which i currently have on the car with no rub (not lowered). Second pic is with the 295's, rubbed. Keep in mind they're rolling on a +56 offset, recommended by Iforged.

996 Jammy - That is quite a bit of difference between the tow tire sizes. I'm glad you were able to eliminate the rubbing issue. I have two questions for you. I know that yourhave 19" wheels with 56mm offset, what is your wheel width, 10", 10.5" or 11"? Also, knowing what you know now, if you had to do it all over again, would you still go with the 19" with 56mm offset? Just curious.

I would ask the same questions as Tim. Looking at your first iteration of the wheel (295's) look fantastic together but the offset is all wrong. Maybe there is less rubbing with the 275's but they just don't look right at all on those rims. The 275's look like they barely fit, show too much rim, and slope from the rim inwards. Not sure I follow the "oversized" by industry standards reference. The size indications on the tire are consistent across ALL tire manufacturers and have to be within a certain degree of variance to claimt he size stamped on the tire. I am afraid NO other tire manufacturer in the same size as your Michelin's will change the fact the wheels are the wrong offset. My question is why would iForge rec'd a tire/wheel combo that is incorrect?

Tim, you are a true tribute to this community and this board, thank you again! I have no other choice than to order the 285/30, I cross my fingers that it will work since it shouldn't be more than 5mm that stick out of the tire as it is now and it also gets 2mm lower upwards, then maybe some more camber.. If that doesn't work I will have to machine of maybe 3-4mm of the rim or simply drive the car to a junkyard Is fender rolling good and won't it harm the rigidity of the rear fenders? Any pics of it? Damn, I hate problems like this, they make car ownership so much less fun Once again, thank you so much!

Thank you for the kind words, and you are welcome! I have never rolled the fenders in any of my cars, but I would guess that the rigidity of the fenders could (or would) be compromised to a degree. How much more flex they would have, I don't know. Since I have never done this, I don't have any pics of rolled fenders. Make sure you let me know how you make out with the 285/30 tires. I would really like to see some "before" and "after" pics.

IMO, I think that concern is a bit silly. Im not sure if you know what rolling fenders does, but all our fenders have a small lip on the bottom, and it basically just bends that up flat, it doesnt touch the "vertical" section of the fender at all. Furthermore though, even if your fender was less rigid, how do you really think that would play out on your car, seeing as it isnt anything structural. Besides the aerodynamic effects, I think you could drive your car without a fender and not notice any less stiffness. -Mark

Dan @ vivid recommended the set up, not iforged, who said dan shouldn't have recommended that tire size for a 10.5 wheel. If i was going with a 295, i shouldve gone up to an 11. Lesson learned to never buy from Dan again as he isn't as knowledgeable as he says he is on all things porsche. Would i prefer them to be cherry and fit/look perfect?! absolutely, but i can live with this setup for now.

Hate to say it James but you got bad advice. That is an issue I would definitely take up with Dan. He seems to be a pretty stand up guy and should remedy the situation.

Thats what i thought, till he said there's nothing wrong with them and forced my cousin to return those kinesis wheels via Amex dispute. Stand up guy? I beg to differ.

Mark, I understand, however, that is the absolute last option for me, I'd rather machine of 3-4mm of the rim before touching the car, ordered 285/30's today, holding my thumbs and pray to God that it will work, otherwise I'm and trashing the car Thanks!

Tim, the kind words are deserved x10 If you were in Sweden I would buy you a I certainly will let you know how it works out, I have no other choice to this day than to order and try out the 285's Once again, thank you for all your time and help!

Well that sucks. Like I said he "seems" to be a stand up guy. But actual customers words are more powerful than an observer like myself since I haven't purchased anything from him.

How important was it to run 4 exact same brand tires on a C4 996? The Pilot Sport PS2 I have only comes in 295 wide, now I have no other choice than to buy another set of rear tires that will not match the front Maybe I should just go with some Pirellis or Yokohamas, they don't have that stupid fat lip on the side of the tire to protect the rim neither... Any input wheter this is dangerous or not?

Slowpoke......opinions will differ greatly on this topic but the bottom line is that Porsche states that you need to have the same tires all around on the 4WD cars because of the nature of how the 4WD system operates. On a 2WD it is ok though not recommended.

OK, and if you give me your opinion? And others here? I have heard stories of people getting problems due to not haveing same brand tires all around, I have heard stories about people having problems although they've had the same brand but wider in the rear and and I've heard stories that having more tire thread in the front or rear can cause problems, seems a bit far-fetched...? Input? Thanks for your time!

Personally I would NOT have different tires in the front vs. back on a 4WD. As well, I would make sure that I am within a safe and tolerable variance when changing tire size as well. For example, less than a 2-3% variance from the orignial tire size that came on the car is acceptable. Personally I would try to get closer to a value less than 1%. All too often you get people that get a higher sidewall to fill in the fender yet have no idea the havoc they can bring upon the cars normal characteristics suc as braking, traction control, etc. Here is a tire calculator that will allow you to put in the factory spec that is made for your car and then you can experiment with new sizes to see what the variance is and then allow you to find the proper tire dimensions to stay within that tolerance: http://www.1010tires.com/TireSizeCal...?action=submit Hope this helps.

LVDell, Arling from Lucent have given me instructions to jack up the car and see exactly where the tire rubs the fender and go from there, will post more after I do this later tonight, stay tuned, if you care Thanks a lot!

Standing by...........

Wooow be carefull machining the rims. You might weaken the wheel. Imho just sell them and buy the proper ones with the correct offset. If you bought them at a dealer I would go there and have a "nice" chat with them Good luck Ronny

If you take some metal out of those rims, they still wont fit, and then you wont be able to sell them, the 285 rear tire is not going to make enough difference. Bite the bullet and order 2 new rears, I know this is not what you want, but its what you will need to do. I have played around with many different rims and offsets for my C2( some think I have a rim fetish) .Techart is a great wheel for our cars , but I would not want to play around with them you need at least 10 mm off to make that rim work.

Now that's the understatement of the year!!!