IS1

I have got my Iforged Seneka's with 235/35/19 up front and 265/30/19 in back. Falken GRB 451 tires and H&R coilovers. The shop has raised the coilovers to there highest perch and I still get occasional rubs on hard bumps? What is the solution to this? Do I need to buy stiffer/adjustable shocks? Have them make an aluminum spacer to get the car higher? Roll fenders?
HELP!

Mach430

Can you push the wheel out further with a spacer? If the company that built your wheels was aware that you had coilovers (prior to ordering), they should have designed them at a size and offset that would not hit the spring perch.

smgC32

Your problem is most likely the wrong wheel offset causing fender interference. I don't think that your tire is comming in contact with the spring perch/collar. If your ride height in the front is over 13.5" from the fender lip to the center of the hub, your tire should clear the lower perch. You are probably at 14.0"-14.25" ride height. In order to check the problem, do the following:

Turn the steering wheel full lock. Jack up one side of the car. Look at the strut assemebly on the side in which the front of the tire is pointing away from the fender (you get a better and easier view on this side). Measure the length of exposed threads on the strut. If you are all the way up to the top, you should have at least 1.5" of exposed threads as measured from the top of the sway bar tab where the threads start, to the underside of the lower collar. This lower collar should be higher than the wheel lip and level with the top of the tires tread. You typically only come into a problem when you run the coilovers at 0"-.5" of exposed threads. Look at the relation between the tires rim bead and the strut housing. How much clearance do you have? Measure by inserting shims between the gap. Use multiple business cards until they stay without falling out. Depending on your tire selection in 235 35 19, you will have 0-3mm of clearance if your wheel's offset is correct for this application. What is the width of your front wheels and their offset? A 235 35 19 should be used on a 8.5" rim width. The working offsets for this rim width are limited to 30-32mm. Anything larger will interfer with the strut tube, anything smaller will rub the fender. Your wheel and tire combo is less than a quarter inch higher from the center of the hub to the top of the tires tread so height should not be the issue here. Good luck and let us know what problems you uncover.

I1 ULOOZ

I would not recommend using spacers unless you absolutely have to.

Mach430

As long as the spacer is TUV approved (such as H&R), there is absolutely nothing wrong in using it. TUV approval is only granted when a product will work as well, if not better, than stock.

However, I would definitely agree if the spacer is not TUV approved.

IS1

Let me re-phrase that it is only the back wheels that rub.

Wiedermann

Mr IS1:
I know the "rubbing" issue has been discussed back and forward sooo many times... and not to **** off Mr Vader and have him choke my using his dark power of the "forged" (as well as many others... the Doc, Vomit.. everyone!! lol)...

Even after the rolling of my rear fenders was completed, when I have more than a total of 2 occupants on the vehicle (including the driver), say anyone on the rear seats, say one or more in the rear, when I go over a hump on the freeway at freeway speeds, the rear tires will rub; and to that, there is no escape. There are other people on this forum that I have been fortunate to meet in person and have seen that they (for those that have mods in suspension and/or wheels with or without tires) also have the same problem… reagardless how well their wheels’ offsets are, regardless how well their fenders are rolled, the cars still rub. That is now to count that in some cases... if the famous wheel's offsets are wrong, then regardless of how well the fenders are rolled the car will rub... one "solution" that is "offered" and it has to come to your personal choice is to choose a wheel offset that is lower than what is needed for the wheel of your choice. This will cause the wheel to "sit in" more inside the fender, which will allow your wheel and tire to travel more up and down inside your fender and possibly (and hopefully) help you avoid any rubbing... the downside to this... and those with engineering majors can probably explain it better than I will ever do, is the wheel simply sits more inside the fender and not flush with the fender as it is designed... not to count that you can opt to have negative camber on your wheels, but then other problems will arise.. again, all a matter of personal choice. Those that have visited the plant in Germany probably have seen the demo little cars they have where you can change the camber adjustment on the wheels and see how those cars freely run.... (negative camber will cause the vehicle to offer resistance on the road... therefore the car does not travel "freely" on the surface --won't "free fall" downhill per say-- however as result the car will have better grip on the road... and to compensate for that negative camber that basically grips the car on the road and doesn't allow it to "freely" go on the road??? whelp???.. basically you have the engine having to use its force to really "push" that car against the ressistance offered by the negative camber as well as the rest of the mass, blah, blah... again... someone with good physics, or engineer can show the mathematical reason of what I said .

Having bigger wheels and tires... The grip is great!!... however, rubbing is a problem... to eliminate that problem???.. whelp???... the solutions have been posted:
-Roll fenders (if done properly so.. .then)
-Take out the interior fender padding (though the tire then will rub against the fender.. so still rolling fender is the solution)
-Put 255/35 R19 on the rear (narrower tires) ... which actually eliminated completely the rubing on my car... however, I opted to keep the 265's on the rear, I don't have often people in my car except my wife... if I have more, then I take other vehicles that I have.

If you have the "correct" offset in the rear where your problem is... you should know that you are "supposed" to rub in situations as you described... there is not too much space when you are done with the lowering and bigger wheels. If you had the "wrong" offset and you forced the wheels to sit

Assuming you have the correct wheel(s) offsets in the area where you currently rub (front, or back.. on this case your problem seems to be only in the rear) AND, your fenders have been rolled properly (inner fender liner has been rolled), NO SPACERS.. I don't want to take anything away from those who have them and don't have "any" problems with spacers, however... and I am sure those that have their phisic formulas more up to "shape" can prove mathematically all the wrongs of having such devices with the centrifugal, centripetal forces, etc, etc and basically show you that the wheel eventually will pop out ripping the bolts and have the car with it... well... lets have those with the numbers show you what I am talking about.. (I have seen those tests many years ago at a mechanical engineer's lab, and the wheels DO pop out...)

In my experience the smaller tires 255/35 R19 did the trick.. at least when the same tests were run with my car under the same circumstances where the 265/30 ZR19 rubbed, the 255/35 R19 didn't rub!.. that was a gain!... just narrower tires...

ALSO, different tires, even on the same exact size are different. I currently have Pirellis on my car, the 265/30 ZR19s in the rear actually bulch out of the rim where are the comparable Michelins 265/30 ZR19s don't! (my problem was finding the Michellins for the front Front: 235/35 Z R19 Rear: 265/30 Z R19 so I ended up just getting Pirellis all around in the same size)... I have seen other forum's members cars (C32s especially) and under the same circumstances during testing, their cars have also rubbed at some point or another

Your REAL solution options:

-Go back to original (ick, ewww!)
-Cut the fender out (heavy mod) which will require body shop work, repainting, etc, but then your problems WILL be gone (with the tire size you have, change it to wider ones and you may have all the problems ALL over again)
-Don't go fast over humps on the road man!!.. what are you doing!!!



Cheers

Wiedermann

SiLvaC32

try to roll your fenders, i don't see the reason why you are rubbing unless you did not tell them you are going to get H&R coilovers.

IS1

OH, yes they knew H&R coilovers were going on and I have it in writing and verbal acknowlegement. I even used the exact tire and brand they specified (Falken GRB fk451). They do have a HUGE 4" rear lip and the rim barely clears the rear caliper. Maybe this is the down side to a nice lip?

bensitto

I have 265/30 19's on the rear and most of the rubbing was on the inner fender where the bumper and rear fender meet. There is a clip that holds them together, I shaved off a small section of the metal clip with a dremel with a metal cutting disc. This solved most of my rubbing although occasionally I do get rubbing when at high speeds hitting dips on the highway, or when I have 4 people in my car. I may have to cut off some more of it to solve the problem.

SiLvaC32

you have a 4" lip?!?! WOW!! i guess that is the problem.... if you had only 3" lip you won't rub at all.

i'd suggest you shave down the clip also... thats wha i had to do.

smgC32

It would have been nice to know that it was the rear to begin with. Also could you please be more specific and state exactly where the rubbing is occuring; inside, outside, condition of tire sidewall?

The building tolerance of the W203 chassis is open to a large margin of error. I have never had a problem with the rear tire rubbing anywhere on my car with both the stock AMG suspension and larger aftermarket wheels, and after the installation of the Carlsson RS's, including the addition of two adults in the rear compartment. I run 18x9.5" wheels in the rear with an ET of 36. I have had both the Goodyear GS-D3's and the Toyo T1-S's without any issues. And I have never needed to relocate the screw that retains the metal fender and bumper cover or file down the junction. I have rubbing problems with the passenger front that no one else seems to have... go figure.

Coilovers have NOTHING to do with rear wheel/tire fitment. The rear set up of the W203 is not a coilover design in that the spring is not sitting over the shock, but rather they are seperate. In fact the spring for our car sits inboard of the rear shock so it would be impossible for the rear spring or the adjustable spring perch/collar to interfere with the wheel/tire. It is also at a point horizontally that is within the interior diameter of the wheel itself. The coilover kits for this car provide the same size diameter rear spring as the factory's and the same size rear shock assembly. Other than the adjustable ride height, there is no difference in fitment.

If your clearance problem is at the outer fender, adding a spacer will only make matters worse. I will assume that you are running a 9.5" rear wheel, which is really the only proper size you should be running with a 19" rim and 265's. The usuable offset number for this size wheel is between 32-36mm typically. Given your 4" lip, your offset number most likely will be way below 32mm. It is impossible to fit a 9.5" three piece wheel with a 4" lip on a C32 without outer fender rubbing problems regardless of where your rear ride height is set, and yours should be close to 14.5" in the rear according to your statement of adjustment request to the installer.

What is the exact specifications on your Iforged wheels? Front and rear diameter and width, as well as offsets front and rear? Are you cutting your tire in the rear when it rubs? Have you put shoe polish on the tire to see where it is rubbing the body panel?