STi weight reduction

So the Team decided before we head out for our first track test session that a few minor modifications to help increase the vehicles performance were required. And the cheapest and easiest way of doing that is by making the car lighter! The STi from factory weighs in at 1270kgs which we hoped to bring down to approximately 1200kgs without major carbon fibre panel work or lexan racing windows.



So besides completing a minor mechanical service (oils & fluids), we got straight to work! Stripping the STi was relatively straight forward; a couple of screwdrivers, spanners, a little bit of pull and tug and there you have it, instant lightness :-D. Now we didn’t just settle on removing seats, carpets and door panels, we wanted to remove as much weight as possible.


We also figured if we remove the sound proofing in the car that would save around 10-15 kg, which was quite considerable. And after a little research we settled on using some dry ice. The dry ice would harden the sound proofing material and by using a hammer or rubber mallet it would break off fairly easy.

The whole car required 4-5 kgs of dry ice to get all the sound proofing off, all the way from the boot right down to foot wells. I did this job on a pretty hot day so that could’ve affected the cooling capacity of the dry ice, but if you’re quite quick and efficient you could probably get the job done using about 3 kgs.

All I did was place a couple of handfuls of dry ice, applied it directly on top of the soundproofing material and left it there for a few minutes till it hardened. Then with the hammer gave it a few hits and it just crumbled. Some of the glued down parts won’t come of so easily though, so you'll need to chisel those bits off.


Dry ice - boot

Now you’re not going to get a perfect finish when you’re done, there’ll be a few scuff marks and traces of glue here and there. But if you really want a clean finish there are a couple of options. One is you could sand down any traces of glue and re-paint the interior or the other option is to use paint thinners. I opted for the paint thinner option simply because I had some lying around in the garage. Just apply a little with a clean cloth to where the traces of glue are and after some vigorous wiping the job is done. Also make sure you’re not in an enclosed area when using the paint thinner. Have the car doors and windows open!!


10kgs of sound deadening

John