My experience with 18" wheel upgrade for R129 - PeachParts Mercedes-Benz Forum

KenSilver · #1 11-01-2004, 05:34 AM

After a lot of idea searching and opinions over the last few months, I finally decided to upgrade the rims on my 93 SL500 from the original 16" to the AMG 5 spoke staggered set that are standard on the 2000-02 SL.

The new set is:
Front: 8.5J x 18 ET 25 with 245/40 R 18 tyres
Rear: 9.5 J x 18 ET 23 with 275/35 R 18 tyres

I've put on Goodyear tires - the Eagle F1 GS-D3. These are not to be confused with the earlier F1 tires. These new ones have the highest rating in the Tire Rack customer reviews in all segments of handling, ride, cornering, longevity etc, than Michelins, Pirellis, Dunlop's and the rest.

So finally, after several weeks of ordering, shipping and sorting, this afternoon I put on the new AMG rims (with machined lips - very nice!) and took the SL for a test ride.

I had always been concerned with the larger wheels that I would have excessive tramlining, sensitive steering and a hard ride, as happened when I upsized my 350SL from 14" to 16" wheels. But it turned out to be nothing like that at all. In fact, apart from some slight - and I mean *slight* - firmness of the ride at low speed, nothing has changed. I needn't have worried about a thing.

There has been no tramlining whatsoever, and even though our secondary roads are a bit like European roads... narrow, windy and bumpy... it hasn't made any difference to the steering accuracy. It's as solid as a rock, handling just like the original wheels.

Steering precision and road feel is just the same.

On the highway/motorway, the ride is perfect right up to 120 km/hr. The car runs straight as an arrow, the ride is comfy and luxurious--just like the smaller wheels, and there's no increase in tire/road noise either.

While I haven't put the tires through their paces because of the 500 mile run-in period, I have no doubt they will be very stable when cornering hard. As for the wet, I don't care - I don't drive when it rains.

So to sum up, all my worries were unrealized. The tires look stunning because they fill out the arches and make the R129 look very pretty, they run as well as the smaller wheels, and there are no bad side effects whatsoever.

If you have been looking to sharpen your SL's looks up, you'll have no problems going to 18" instead of 17", I guarantee it!

I'm taking some photos of the wheels and others upgrades on my SL tomorrow, and will put them up here soon after. And change my sig pic too!

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons: http://www.kensilver.com/SL
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate (my wife's)
~1999 Suzuki Grand Vitara. black & silver
~1991 Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

Bruce Hat · #2 11-01-2004, 11:13 AM

Hey Ken, Glad you like the new tires/wheels. The AMG's look great on the SL. Looking forward for some pictures.
http://www.peachparts.com/shopforum/attachments/mercedes-benz-sl-discussion-forum/19287-consider-before-buying-sls-sl-jag-signature.jpg
Bruce

SilverSL500 · #3 11-01-2004, 12:02 PM

Quote:

Originally Posted by KenSilver

and I mean *slight* - firmness of the ride at low speed, nothing has changed...

the ride is comfy and luxurious
Ken Silver

Hmm. I've got the same setup, but using Michelins. I would not call my SL's ride "slightly firm", and no way is it close to comfy and luxurious!

I'll have to try those Goodyears next time

S

KenSilver · #4 11-01-2004, 05:45 PM

Here's some shots with the new wheels.

Ken Silver
--------------
1999 Mercedes SLK, 1999 Suzuki Grand Vitara, 1993 Mercedes SL500, 1991 Daimler (Vanden Plas).

Here's the original factory 8 holes before the change:

KenSilver · #5 11-01-2004, 06:11 PM

Quote:

Originally Posted by SilverSL500

Hmm. I've got the same setup, but using Michelins. I would not call my SL's ride "slightly firm", and no way is it close to comfy and luxurious!

Sure, compared to my Daimler, this ride is quite firm. It's what I've been accustomed to in a sports car, but this ride is still better than our SLK - and the Grand Vitara - by a long shot.

The Eagles have a softer sidewall than most of the contenders, and maybe this makes a difference. I'm running them at 40/42 psi which is higher than standard (though not for low profile tires) and it's still quite comfortable.

And then there's the 'butt' factor

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate
~1999 Suzuki Grand Vitara. black & silver
~1991 Jaguar Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

ericgr · #6 11-01-2004, 07:16 PM

I was told by a mechanic that the front ends on these cars are not designed to withstand the added abuse more metal, and less cushioned rubber, has to offer. This made sense to me as well. While these larger rims have a unique look to them, I have struggled with the argument that more metal and less rubber is an improvement despite all the new cars doing it. Your car looks beautiful and hopefully the new tires and rims will work out well on the car, maybe you can keep everyone up to date over time and all will be well.

KenSilver · #7 11-01-2004, 08:40 PM

Quote:

Originally Posted by ericgr

I was told by a mechanic that the front ends on these cars are not designed to withstand the added abuse more metal, and less cushioned rubber, has to offer...

Eric,
That's an interesting comment. I'd heard that the suspension and steering components remained basically the same right through to 2000-02, when these wheels were standard with the AMG body. So it seems to me to be an approved update. Let me know if you hear anything else on these lines, but hey - I can't go back!

And yes, I will keep you updated... if only to say how happy I am!

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate
~1999 Suzuki Grand Vitara. black & silver
~1991 Jaguar Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

KenSilver · #8 11-01-2004, 11:22 PM

Quote:

Originally Posted by Bruce Hat

Hey Ken, Glad you like the new tires/wheels. The AMG's look great on the SL...

Thanks Bruce,

On another subject, have you got underbody pics of your new exhaust tips? There's a couple of things I couldn't figure out from your explanation that would be solved with a picture or two from underneath.

Since my AMG bumpers and sills will be here in less than 2 weeks, I'm trying to get the tips organised as soon as possible. Your ideas welcomed.

Ken Silver
--------------
1999 Mercedes SLK, 1999 Suzuki Grand Vitara, 1993 Mercedes SL500, 1991 Jaguar Daimler.

ericgr · #9 11-02-2004, 06:39 AM

my comment was general with regard to an arbitrary older MB and these wheels. Your info is better and specific to your car so fortunately it looks like you should be in great shape. I did not know your model was already in spec for them. Your car looks beautiful with the new tires and it must be an incredibly powerful and crisp drive, congratulations

Bruce Hat · #10 11-02-2004, 10:51 AM

Ken, your car looks great, I mean really great. Sweet ride. It makes me want to get the lower moulding on my SL painted to match. . I have 17" amg's on mine with "yoko aviddbs2". The ride is firm, but soft and I like it. I like all your improvements. BTW I'll take some pictures of the tips and post them.

KenSilver · #11 11-02-2004, 12:28 PM

Quote:

Originally Posted by Bruce Hat

Ken, your car looks great, I mean really great. Sweet ride. It makes me want to get the lower moulding on my SL painted to match. . I have 17" amg's on mine with "yoko aviddbs2". The ride is firm, but soft and I like it. I like all your improvements. BTW I'll take some pictures of the tips and post them.

Thanks Bruce! Don't get dirty under there!

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate
~1999 Suzuki Grand Vitara. black & silver
~1991 Jaguar Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

KenSilver · #12 11-02-2004, 12:31 PM

Quote:

Originally Posted by ericgr

my comment was general with regard to an arbitrary older MB and these wheels...

Eric,
Yes, I'd heard those comments about the 107s. Hopefully it doesn't apply to mine.

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate
~1999 Suzuki Grand Vitara. black & silver
~1991 Jaguar Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

elau · #13 11-03-2004, 10:34 AM

Ken,
Beautifully done!! How hard is it to change out the side grille?

KenSilver · #14 11-03-2004, 12:38 PM

Quote:

Originally Posted by elau

Ken,
Beautifully done!! How hard is it to change out the side grille?

Thanks elau,

Easy, but Expensive! I bought these genuine panels from the previous owner who originally paid over US$2,000 for them. They consist of the complete lower body parts - the 2 slot panel, lower door, and panel ahead of the rear wheel.

My paint shop did the changeout, and I paid them the usual 20 gold pieces plus a share of my holiday home and free overseas trips for life.

I gather it was an easy change, with the parts clipping into position. The fit is perfect. There are kits around which have only the front 2 slot panel, but I'm told they are fiberglass - not the special MB plastic - and I've heard the fit is not as good.

At the beginning of my research into whether I needed /really wanted to do this, I thought I only needed the 2 slot plank. But MB are cunning - they changed the design ever so slightly so that all three parts are required for a match. I actually had to put the new panels against my SL to see the difference, but once they're on, it is a bigger change than I realized.

If you look carefully in the last pic, you may be able to see the slight curved fluting along the bottom of the panels, and a 2cm flat line at the bottom where it meets the top of the sill.

I only made these changes because I have ordered the genuine AMG Sports body parts (both bumpers and sills, due here on the 10th), and it would not match the original panels.

Ken Silver
--------------
~1993 SL500, glistening triple black, xenons
~1999 SLK 230 Kompressor, silver/black leather, CD, immaculate
~1999 Suzuki Grand Vitara. black & silver
~1991 Jaguar Daimler, shiny grey/grey leather, best in country!
~ex 350SL, 230E, 280E, MX5 and a lot of other makes not nearly as nice.

spinedoc · #15 11-03-2004, 04:18 PM

Congrats Ken on the 18's, I know you were vacillating betw those and the 17's, glad to see you made the ONLY right decision!!

In regards to the Michellin's and a harsh ride, I beg to differ. I had the Pilot Sports and I think the ride was quite comfortable. I now have the Pilot Sport A/S and they are an even more comfortable ride (but much worse handling).

The only issue with the Michellins is how fast they get eaten up. What mileage are the F1's rated for? Maybe I will grab those next time I need to shoe the horse.