So you pretty much want to change the final drive just to make 2nd, 3rd and 4th gear rev higher?

Sure sounds good on paper, but I cringe at the thought of your DSM being constantly revved out super high the whole way around Shannonville. I say your car will overheat by the end of the first lap.

I recall Daren Peacock pedalling his 2g around Cayuga last year becasue his coolant temps were getting hot. Sure as hell looked like the DSM couldn't even handle a single all out lap.

Your forgetting it's a DSM. I say you actually get it out on the track and see how the car likes the current setup before keeping the car revved near 8.5k for 2-3 km straight.

If it were me, I'd keep the gear ratio as is, and keep a smaller turbo, which makes more power under the curve, and stay in a gear longer rather than constantly revving the car high and shifting through several gears because you want it to behave like an evo3. Will the car weigh ~2500lbs as well like an evo3?

I'm almost confident you'll have overheating problems as is. I've seen it enough already. Just trying to be realistic here. This is not Gran Turismo, lol.