BMW E30 / E36 / E46 - Roll-center / bump steer correction -kit

MRT-20003-9W
  • €427,00
    Unit price per 
(Excl. VAT)
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RODOBAL rod end / spherical bearing upgrade (service) available for this kit, click here

Roll-center / bump steer correction -kit for BMW E30 / E36 / E36 M3 / Z3 / Z3M / E46 / E46 M3 / Z4 / Z4M models (excluding E30 M3 / E30 iX / E46 xi/xd models)

Another version of the popular kit now available! Main features:

  • 20mm roll-center correction

  • 20mm bump steer correction

  • Original steering ratio and Ackerman angle with no angle increase

  • All new one-piece fasteners and billet castle nuts with PVD coating

  • Lightweight AW-7075 aluminum tie rod extensions

  • Bump steer adjustable ±5mm

  • Please refer to wheel fitment chart and check compatibility with your wheel/knuckle combination

  • Control arms and/or knuckles/spindles shown in the pictures not included

  • E36 type tie rod inner ends must be used on all E30 applications

  • E90 type longer tie rod inner ends must be used on all E46 / E46 M3 control arm applications

  • Control arm bore needs to be tapped for bearing retainer insert on E30 M3 "Dorman" and E46 M3 control arms, thread tool included **

  • Comes with mounting hardware and of course MRT Engineering decals


Why do you need one?

When lowering your car (BMW E30 / E36 / E46 etc.) the front end geometry goes wrong. The main purpose of the kit is to correct these geometry issues.
The extended mounting stud changes control arm pivot point vertical distance by 20mm correcting the roll-center and camber curve.
Tie rod end pivot point is also changed by 20mm in vertical direction which corrects the bump steer curve.

Does it fit my car?

The kit can be combined with most of the E30 / E36 / E46 control arms and knuckles/spindles. See available variations:

Outer joint size:

  • 32mm (E30 M3 "Dorman") thread tool included **
  • 41mm (E30 non-M / E36 M3 / Z3M)
  • 48.5mm (E36 / Z3 non-M, E46 / Z4 non-M aftermarket, E46 M-Sport / Z4M)
  • 33mm (E46 M3) thread tool included **

Spindle/knuckle:

  • E30 non-M
  • E36 / Z3 non-M
  • E36 M3 3.0
  • E36 M3 3.2 / Z3M
  • E46 / Z4 non-M / Z4M
  • E46 M3

Is it easy to install?

Instructions, PDF

Assembly drawing, PDF

The kit comes with instructions, if you know how to change a control arm or an outer joint, installing this kit is basically not any harder. You'll need a press for removing the old outer joint and installing the new outer joint, no other special tools needed.

If you need any further info please contact us!

How about the lifetime and service of the kit?

The kits have been proven on street and track applications by hundreds of our customers. We're constantly doing R&D to make the kits even better, all improvements are based on customer feedback which is very important to us.
We have proven the very same bearings with no maintenance for 20,000 kilometers, through the year, in daily use without signs of excessive wear. When the bearing life comes to an end, they're easily replaceable! Bearings are available around the world from automotive and industrial dealers and any of the spare parts can be also bought separately from us.

We want to keep our customers 100% happy thus we're only using the best materials and manufacturing processes available. All parts are CNC machined: aluminum parts are aerospace grade AW-7075 with hard anodized finish (silver and black), mounting studs are made of highest quality CrMo tool steel and small spacers/adapters used on the kits are 316L stainless steel.

We use DHL Express shipping for all items. Please find your order tracking information from DHL website.