Subaru GC8

Due to a accident that I had I was forced to scrap my project which was a Honda Civic EG which although was a daily car as well it also had all the goods for the track (Hardrace bushes , camber kits , Tein Flex Z coilovers and much more. ) Plan was to built the engine in September and start twicking it and hitting the track . Unfortunately as mentioned being a road car it was involved in a crash (come out ok) but the chassis didn't make it or at least in my eyes it was gone . Was lucky enough though to find a quite good GC8 . Which needs work yes but its in good condition and a good base .

Now as a novice 4wd car driver (alsways had fwd car and some rwd) I can say the car is quite quick in the mountain pass and quite good . Now it has Bilstein PSS9 coilovers , 18inch rimsand OEM size brakes . I would like some opinons from anyone with more experience with these cars than me . In a previous post I had asked about the oem strut brace (carbon) and a lot of positive responce in regards of it so I am on the look out for one . Now should I go 17inch rims ? Should I keep the PSS9 , or go to another brand ? Also in terms of brakes should I keep the oem size with better disks and pads or go for bigger ? Plans in terms of engine is a fmic , td05 or a vf35 or similar , standalone ecu to take a dvantage of the HPAcademy webinars and learn more how to tune antilag , flatshift , avcs etc. So at the moment not that much power but to learn through my car what is shown to me here and HPA .

The car will be a little bit of everything daily , if possible to hit the track a few times (Covid has restictions) and mountain passes at least once a week .

TIA .

Firstly, which Model Year GC8 is it? There are a lot of changes that have been made to the GC8's in their lifetimes so knowing which version it is will greatly assist in what is recommended.

With the brakes, even the standard 4 pot calipers and rotors that are fitted to the later model vehicles are very marginal for fast road use, and will give up after a few track laps, even with upgraded fluids and pads. The calipers being cast iron retain a lot of heat and this leads to issues, the seals in the calipers are also a weak spot with elevated temps. The 2 piston calipers should never be used anywhere near a racetrack. The rears brakes do not do a lot of work on these vehicles so they can be left standard for longer, but if you do change the front calipers to a larger caliper with bigger bores for the brake pistons then you can run into balance issues on the standard master cylinder.

The gearboxes in the early vehicles are made of glass and do not appreciate being rushed on shifting, the later (MY99 on) boxes are slightly better as they made some changes to the boxes that made them less likely to flex under load and thus keep everything aligned, but they are still vulnerable to damage from hard usage.

DO NOT fit an uprated clutch to these cars, Subaru deliberately used a clutch that would slip to act as a fuse for the driveline, replacing the clutch with a heavier duty unit will lead to breakages in the gearbox and driveline.

The earlier vehicles ran a smaller top mounted intercooler, replacing this with a unit from a later model will not gain a lot performance wise, but it will reduce the amount of heat soak that the cooler suffers from and will keep the inlet charge cooled for longer under high loads.