I'll try to make this simple. You want the 300x28 front brakes, with 278x24 rear brakes. That will bolt on with no mods, other than tweaking the splash shields to clear the rotors, and needing 16" front wheels to clear the calipers.

The 300x28 front brakes are used on the early 500E (lightweight Brembo calipers, very hard to find) and most early R129's (iron ATE calipers), actually all SL320's and most early SL500's I think? These are a little hard to find used, but easier to locate than the Brembos.

The 278x24 rear brakes are used on all W124 V8 models for all years (1992-95 400E, 500E). You could use the 278x9 solid rears, found on almost all M104-powered cars and most wagons. However the caliper is abnormally heavy and there's not much more weight penalty when using the vented stuff, but the 24's are harder to find used, while the 9's are plentiful and cheap. If you can't locate the 24's, the 9's would be a decent upgrade from your stock 258x9 rears.


The E320/E420 brakes, 274x25mm, will NOT fit unless you either swap the lower control arm to the type with the welded ball joint, OR you install the R129 knuckle & hub used on the E420/E500 with your old lower control arm. If you can find an E420 in the junkyard and swipe the caliper AND knuckle/hub really cheap, that would be great. Or, find an E320 and get the lower control arm and caliper - spring compressor required, and the LCA should have good bushings & ball joint. Otherwise, it's more work and more parts to source. I originally thought the E420 front setup would fit, but I was wrong - it only fits the W201's (except the 16v)! D'oh. I sold those to a 190E guy and bought a set of the SL320/500E calipers, they're in my shop waiting to get painted, and maybe installed this winter.

Don't bother with anything larger than 300mm front, or 278mm rear, unless you plan to take the car to the racetrack. The early 500E brakes on a lightweight 124 chassis, with Porterfield R4-S pads, should be more than enough. For normal street use, the stock brakes are surprisingly decent with R4-S pads, stainless lines, and good brake fluid.



HTH,

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Dave
Boise, ID
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I put 500E brakes and it required some time with a hammer to make them fit.

Then I have some 996 turbo brakes going in and they require special fabrication again.

if they owe you money, look around for an M104 engine swap or 94-95 conversion for your W124

Which 500E brakes... the early 300mm/Brembo calipers, or the later 320mm/Ate calipers? In the rear the splash shield must be cut (or hammered, I guess).

i only bought the fronts. they were from a guy here on mercedesshop!

Dont you guys think using Porsche calipers on a front engined car isnt such a good idea? Just seems the brake balance would be a bit off.

As for suspension, the OE sportline kit seems to have gotten good reviews. If the steering box fails, maybe install the sportline set up with the faster gearing?

IMO, OE brake parts from heavier/faster models are best for daily drivers.

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2002 VW Golf TDI-169,000 miles B20

In general, yes it would be advisable to upgrade both front AND rear brakes for proper balance. Piston sizes are important too. My setup should work pretty well on most 124/129/201 models. Custom fabbing Porsche stuff has a high bling factor, but performance wise there is no adavantage over other solutions like the OE parts or StopTech kit...