XYZ Racing Pro Rally Coilovers — Maserati BITURBO SI φ52 welding (PCD: 4X98) 1986-1991

The Biturbo SI’s turbocharged front-engine, rear-drive layout was never built with loose gravel and snow stages in mind, and its factory strut top mounts reflect that. XYZ Racing’s Pro Rally coilover for the φ52 Welding configuration replaces that bolt-in limitation with a fabricated, welded-in top mount built for the loads that competitive rally driving actually generates.

This is the Φ52 Welding variant specifically, which means the 52mm strut body is paired with a top mount designed to be welded into a modified body shell rather than dropped into the stock captive fitting. It is not a weekend fast-road part. It is built for teams and privateers running the Biturbo SI on stage.

What this coilover does for your 1986-1991 Maserati Biturbo SI

A welded top mount removes the compliance and flex that a factory rubber-bushed captive mount introduces under repeated hard landings, which matters enormously once you are running a 38-year-old chassis over rutted gravel or ice at speed. The Biturbo SI’s nose-heavy turbo four already loads the front struts hard under braking into a stage corner; a mount that cannot move independently of the body keeps that geometry consistent lap after stage after stage. Ride height and damping are adjustable on the coilover body itself, so you can raise the car for suspension travel over crests and washouts, or firm it up for a faster, drier stage, without swapping components. For a car this rare, that adjustability also means one set of coilovers can be re-tuned across a season rather than replaced.

About the Pro Rally coilover

XYZ Racing builds its rally gravel and snow suspension in two distinct forms. The first is an amateur-spec unit that installs directly onto the original chassis mounting points, no bodywork changes needed. The second, which this Φ52 Welding kit belongs to, is the professional type: it requires the body to be modified so the top mount can be welded directly into the shell. That trade-off buys a stiffer, more direct connection between the strut and the chassis, which is exactly what a car competing at the front of a rally field needs when the factory mounting hardware is decades old and was never rated for stage-pace impacts.

Fitment for the Maserati Biturbo SI (1986-1991)

This kit is built for the Maserati Biturbo SI (chassis code MS03) across the 1986 to 1991 production run, in the φ52 Welding configuration with a 4×98 PCD. Because the top mount is welded rather than bolted, fitment work should be planned alongside a fabricator familiar with the Biturbo’s shell.

What buyers also search for

• Maserati Biturbo SI rally coilover kit for gravel and snow stages
• Maserati Biturbo SI Pro Rally suspension with welded strut top mount
• 1986-1991 Biturbo SI 4×98 PCD coilover for competitive rally builds
• Professional-spec rally suspension conversion for the Maserati Biturbo SI

This is a fabrication-level install for a genuinely rare rally platform, so check the φ52 Welding spec against your car before ordering, then configure yours below.