W124 E class alloys / sunroof queries

[willoughbybrown]

First post!

I have a 1993 W124 E200 saloon and want to smarten it up a little. I have been offered some alloys from a W210 E class Elegance saloon (apparently the standard alloys)/ They are the same size as the W124 wheels, being 195/65 R15. Is there any good reason why I should not fit them to the car? I am worried about fouling brakes, needing spacers, needing different bolts etc.
I also have an offer of SL320 alloys from a 1993 car. The wheels are 225/55zr 16 and seem a little too big for the car. Would they fit, and if so would any recalibration of the speedo be required?

I also have a problem with the sunroof. It does not leak, but the leading edge is slightly raised and at motorway speeds the noise is quite intrusive. Has anyone had a similar problem?

This is my first benz, having worked my way up from BMW's and a Porsche 924. Sorry if I am weak, technically speaking, on the marque.

Thanks

Andy

 

[william silver]

alloy wheels

The tyre size might be the same but you must check the ET measurement (hub face to wheel edge measurement) to ensure the wheel does not foul either the wheel arch or the inner wheel arch.

 

[talbir]

195/65 15 is very different from 225/55/16.

There is approx a 3% difference in rolling diameter - so your speedo reading with the 225/55/16's would be also approx 3% too slow.

You need to ensure the rolling diameter is the same when moving up wheel and tyres sizes.

195/65/15 :

65 represents the height of the sidewall as a ratio of the width of the tyre, i.e. in this case, 65% of 195mm. Given 1 inch = 2.54cm, diameter of wheel plus tyre is :

2 * (195*65%) + (15*2.54*10) = 634.5mm


For the 225/55/16 :

2 * (225*55%) + (16*2.54*10) = 653.9mm

So diameter difference is approx 3% - which is too much. Need to have this difference within 1%.


The second issue ie regards the Offset, or ET number as it is known. Offset means absolutely NOTHING without considering the WIDTH of the wheel. The two need to be considered together. If two wheels have the same ET number but one is 7.5" and the other 8" then you have a 1/2inch difference -which can be enough to cause plenty of damage. If the width of the wheel increases, then generally the ET should be decreasing.

Also the offset is the measurement from the hub face to the centre line of the rim, not the wheel edge. If the hub face extends beyond the centre of the rim towards the inner wheel arch, then it is a negative offset (as seen on some trucks and Widebody MB's such as W126 SEC's which had 11" rear tyres with an ET of -12.7 !). But with standard MB's the offset is always positive as the hub face does not extend beyond the centre point of the rim.

I am pretty certain the wheels on the SL320 will not work on the standard W124 - given the tyre size is 225/55/16 they are likely to be the original MB 8-hole or 16-hole, 8 inch alloys with ET 34. The only W124 these will work on is the E500 which has very flared arches and similar suspension components to the SL500.

The W210 alloys will likely work but the w210 may have a higher offset. If they are the same width, this won't neccesarily be a problem, but they sit a little deep inside the arches. If the width is the same, then ensure the ET number is not more than +/- 5mm different.

IF you buy original MB wheels, then bolts will not be a problem. All MB bolts (at least for models upto 1999) have a shaft length of 40mm. However, wheels from the S-class W140 models have a bigger diameter bolt, 14mm, whereas W124/w126/r107/r129 have 12mm diameter bolts. It's when you fit aftermarket wheels that bolts become an issue - too long and they foul the handbrake shoes on the rear.

Spacers- avoid on the fronts if you can and only ever use spacers TUV approved for front usage (otherwise it'll invalidate any insurance).

Wheels which are the wrong offset/width combination can lead to rubbing on arches (inner or outer), hitting the inner track rods on turning, or not provide adequate clearance from the brake calipers.


Talbir

 

[willoughbybrown]

Thanks

Thankyou for your replies. Decided to keep the car as it was intended and just change the tyres.

Andy

 

[turnipsock]

What about the 16" wheels with 50 profile tyres. It would look good but you would feel every bump and British roads aren't that smooth.