If you can get a 1000cc jimny engine ( baka turbo pa) you're in luck.Maybe you can adapt weber carbs from an old cortina in your 3 cyl. Its been done by a Zuk racer. Cone types are more effective since air is rammed thru but a good round one is more efficient than the ordinary paper filter. Just dont get the ones with cheap foam, they end up in the engine. Think K&N. I used to play around with a Starlet & I know the feeling of lusting after speed. You're quite admirable