Porsche 911 - Using Gtechniq C4 Restorer to Renew Plastic Trim Colour

The scuttle panel around the windscreen of my Porsche 911 has become quite discoloured and is no longer the dark black as originally supplied, now more a dull grey colour as the sun has faded it over the years.

I had been advised that a product called Gtechniq C4 was available and would restore trim back to its original colour so purchased a bottle of it. The cost is quite high and the bottle is tiny - around £25 for 15ml of Gtechniq C4 but that also came with an applicator, microfibre cloths and cleaning solvent too.


Porsche 911 - Using Gtechniq C4 Restorer to Renew Plastic Trim Colour

The instructions are that the area to be treated needs to be perfectly clean so the pack I bought also includes IPA IsoPropylAlcohol to wipe it with beforehand to remove any residues before applying.


The applicator takes a tiny drop of C4 and it covers a surprisingly large area. Having treated the whole of the trim along the front of the Porsche 911 windscreen the bottle of Gtechniq C4 looks barely touched.

The shot below shows the top half being treated compared to the untreated bottom section with a significant difference between them.

Porsche 911 - Using Gtechniq C4 Restorer to Renew Plastic Trim Colour

The result of the Gtechniq C4 being applied looks very impressive. The proof will come over the next few weeks and months to see how well it stands up to the UK weather. The details claim it will retain the look for around 2 years. If this is the case the small 15ml bottle will last as long as the car!

 Porsche 911 trim once Gtechniq C4 has been applied to half of it (left untreated, right treated)

Porsche 911 trim once Gtechniq C4 has been applied to it (below)