[Sabertooth^2]

4: It's the same pump. Your info was wrong. I was running 15psi boost on the stock GS pump as well. It's a 240lph pump, same as an Evo
5: Yes go bigger. If you're going OEM, 565cc Subaru are a better choice. Beware, they're not as good to tune with as an aftermarket performance injector, and most of them don't flow 565cc
6: these cars don't respond well to piggybacks. For $550us you can buy actual tuning software for the stock ECU and be able to change basically everything.
7: stock plugs are already cold. Going 2 steps colder will likely result in issues when not running the nitrous. I haven't had issues on stock plugs at 28psi boost
8: a lot of math involved. Keep torque under 250lb-ft
9: that's fine

 

[Sabertooth^2]

Here it is priced in CAD

FI Tuning Access | Speed Farm Garage

As an alternative to going standalone, FI tuning can be done with Fastworks. This is the tune choice for running nitrous/superchargers/turbochargersIt's a very complex job, and without the vehicle in person, it can't be done to 100%. Think of this not as a tuning service, but as creation of the...

www.speedfarmgarage.com

 

[Sabertooth^2]

Can you tune in launch control?

Yes, for manual trans cars

It works by being enabled when the clutch is pressed in, and speed is below a set limit. When both of those are true, it sets a launch control rev limiter. All fully adjustable

 

[Sabertooth^2]

If you don't plan to run 100+ octane race fuel or alcohol, skip the 11.5:1 pistons. I usually sell forged aluminum 8.5:1 for FI applications on pump gas.

These are the usual upgrade. If you wanted something higher, let me know. I've got no idea what shipping costs or times would be, however, to Ukraine.

4G69 87.5mm Piston Set (4) | Speed Farm Garage

Wiseco Sport Compact Series pistons, set of 41400HD seriesBore Diameter 87.50Compression Height 28.87Forging Type StruttedOil Ring Thickness 2.8Piston Material 2618Piston Pin Included YesPiston Pin Material 9310Piston Volume -21.00Product SeriesSport CompactRingset IncludedSecond Compression...

www.speedfarmgarage.com

Honest answer though, at 250hp goal, keep it stock, run a 50-75 wet shot above 4000rpm, set up your tuning, and call it a day

 

[Sabertooth^2]

100 mon+ron/2, 100ron, or 100mon? I'm a bit confused on your location, so can't really tell what scale you're using. But I'm talking in North American MON/RON/2

And no, 4G64 pistons will reduce compression, and a thicker gasket will again reduce compression.

A custom camshaft from Brian Crower would sort you out power wise.

I could get flat top pistons or domes if you did want to go higher still. Eg, a 0cc will get you 10.57:1. A +1.9 is the highest I see Wiseco going which would give 10.9:1, which isn't unreasonable on 91+ fuel.

 

[Sabertooth^2]

FI tune, 750 CAD

For the cost of a proper nitrous setup though.... I really suggest going turbo instead. Cheap and nitrous means heavy limitations, or expensive controllers with medium sized limitations

Take bottle fill costs into account too, and think about how much you'll use it, and if you'd rather a car that ALWAYS makes more power or just when you spray