u/Muted-Can4546

Hello everyone, I am planning a project build with a very specific goal: I want to achieve the famous, sharp, highly communicative, and progressive mechanical steering and handling feel of the Ford Mondeo ST220.

Essentially, I want to build a "RWD Mondeo" (or a perfect "pseudo-RWD" in the case of the ST220 itself by eliminating understeer). I am deciding between three vastly different platforms and have mapped out how to modify each chassis to eliminate factory numbness and get that precise mechanical connection.

I would love to get your thoughts, engineering insights, and feedback on these three potential setups!

1. Limited Slip Differential (LSD)
   • Mondeo ST220: Helical type (Quaife ATB QDF41Z)
   • Jaguar XJR: Helical type (Quaife ATB GKN 14HU)
   • BMW E46 330i: Helical type (Quaife ATB QDF14N)
2. Suspension & Dampers
   • Mondeo ST220: stock
   • Jaguar XJR: Bilstein B6 (Performance dampers on stock springs)
   • BMW E46 330i: Bilstein B12 Pro-Kit (B8 dampers + Eibach springs)
3. Anti-Roll Bars (Sway Bars)
   • Mondeo ST220: Uprated rear bar (22 mm Hardrace) to rotate the rear, stock front bar.
   • Jaguar XJR: Stock front bar (33 mm) + Uprated rear bar (20 mm Ultra Racing) to kill the yacht-like body roll.
   • BMW E46 330i: Hollow 26 mm from E46 M3 (front) + Solid 20 mm from E46 Cabrio (rear).
4. Chassis & Subframe Reinforcement
   • Mondeo ST220: None required.
   • Jaguar XJR: None required.
   • BMW E46 330i: Yes, mandatory. Rear subframe chassis plates must be welded to prevent the floor from tearing.
5. Bushings
   • Mondeo ST220: OEM (stiff enough from the factory).
   • Jaguar XJR: Purple Powerflex polyurethane bushings on the rear front lower control arms + rear subframe main mounts (to stop the subframe from squirming).
   • BMW E46 330i: Purple Powerflex on the rear subframe + trailing arms. Front: Z4 M eccentric control arm bushings to increase caster to ~6.5°.
6. Alignment Specs
   • Mondeo ST220: Front Toe: 0.05° total (Toe-in) for sharper turn-in with the LSD. Rest is stock.
   • Jaguar XJR: Front Toe: 0.05°, Rear Toe: 0.10°, Front Camber: -1.0° to -1.2° (via custom shims). Rear Camber: OEM stock (~ -0.60°) to keep the rear progressive.
   • BMW E46 330i: Front Toe: 0.05°, Rear Toe: 0.10° (sharp, playful setup), Front Camber: -1.0° to -1.2°, Rear Camber: -1.3° to -1.4°.
7. Steering Adjustments
   • Mondeo ST220: Stock.
   • Jaguar XJR: Steering rack internal travel limiters reduced by 50% + 15mm front wheel spacers (fixing the notoriously awful factory turning circle).
   • BMW E46 330i: "Purple Tag" steering rack (short ratio from E46 Compact) + polyurethane steering guibo.
8. Power Steering Pulley
   • Mondeo ST220: Stock.
   • Jaguar XJR: Uprated larger pulley (+10-15%) for a heavier, more mechanical steering feel & pump protection at full lock.
   • BMW E46 330i: Uprated larger pulley (+10-15%) for a heavier, more linear steering feel.
9. Weight Reduction & Distribution
   • Mondeo ST220: None.
   • Jaguar XJR: All-aluminum performance radiator to reduce heavy overhang weight in front of the front axle.
   • BMW E46 330i: None.
10. Wheels & Tires

• Mondeo ST220: Balanced OEM 18" (225/40/18).
• Jaguar XJR: OEM or lightweight forged wheels (255/40/18).
• BMW E46 330i: Lightweight wheels, sharp square configuration 225/40/18 all around (to keep the rear rotating instead of staggering).

11. Engine Weaknesses & Reliability Flaws

• Mondeo ST220: Oil starvation in long high-G corners (oil pan lacks proper baffles = spun rod bearings). Poor cooling of the rear cylinder bank.
• Jaguar XJR: Plastic timing chain tensioners and guides (1st/2nd gen fail; must upgrade to 4.2L metal 3rd gen). Nikasil cylinder bore risk on pre-2000 models.
• BMW E46 330i: Massive oil consumption (stuck/clogged piston rings, brittle valve stem seals). Oil separator (CCV) freezing/clogging. Brittle DISA valve flap & worn VANOS seals.

12. Main Chassis & Concept Limits

• Mondeo ST220: FWD Layout. Limited launch traction from a standstill, especially in wet conditions.
• Jaguar XJR: Weight (1.75 tonnes) & old 5-speed automatic (lacks a 6th gear and true manual mechanical connection).
• BMW E46 330i: Chassis cracking tendency requires heavy upfront welding. Shorter wheelbase makes it snappy on the limit compared to the Mondeo.

Overally the Mondeo is the cheapest & easiest build, though it's limited by the FWD platform, i never rotate around its axis. The BMW requires the heaviest mods, but is closest to what I want. Jaguar is in the middle, but is limited by its weight.

Which route would you choose to build the ultimate "RWD Mondeo" experience? Looking forward to your technical insights!

How much does your E46 communicate? I mean progressive load, transfer of forces in the suspension, self-aligning torque, grip, etc. The thing old Fords (Mondeo mk3, Focus mk1) did.

Viable or not? From what I've looked, there's several centimetres between the wheel and the damper now (I have ET 12 and 6.5J). Anyone has experience with this setup?