:: Fitting a Silverstone Spoiler ::

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Left are the part numbers for the standard Silverstone rear spoiler, the fitting kit and the 1994 BTCC style jacking kit that raised the rear spoiler up into the air flow

Place the rubber feet on the bootlid and then the spoiler on top to obtain the correct position; remove the spoiler, leaving the feet in place.

Tape the feet to the boot.

Once done, measure the distances to the edge to make sure that the spoiler is equally spaced on both sides.

This is the underside of the AC Trofeo BTCC 155 spoiler that is not available anymore. It was based on the 155 Silverstone spoiler with the jacking kit fitted, raise a further inch and the middle leg removed.

A metal strengthening plate is provided with kit, use this to mark out the holes on the boot lid.
Put plenty of masking tape around the area to minimise damage if the drill slips. Now drill the holes. The boot is double skinned so you need to drill through two layers towards the front of the spoiler.
You will need to remove the rubber grommets and bump stops from the inside of the boot to gain access to the underside to put the bolts and washers in.
You may have to nibble / bend some metal away to allow you to get a socket in for the bolt head towards the rear. This can be done neatly and covered with the rubber bump stop.
Once the holes are drilled, paint the bare metal edges with primer to protect from rust. Make sure you get as much swarf / loose metal out from between the boot skins as this will rust over time and cause corrosion.
Insert the bolts and tighten, though not too tight at the front as it will buckle the boot.

Here is the AC Trofeo spoiler from the rear.

It looks a factory item in my opinion as it uses the standard rubbers etc and has the aerodynamic lip on the plane of the spoiler to give downforce.

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