random thought - hybrid td04, or td05 for track day car
 

Sat here thinking about turbos for my track day toy. Basically, engine-wise a 2.1 with bug eye WRX heads, 3" exhaust, STI tmic.

My current turbo is a TD06-20g (billet), which doesn't really get on song until 4k RPM, so I'm looking at building myself a new turbo, as even though I don't mind the late spool for the road, on track I think it might be a hindrance.

My current favourite choices are either:

- TD04 with billet 19t (or 20t) wheel
- TD05-16g (with billet wheel)
- TD05-20g (with billet wheel)

Obviously the td04 would spool the best, and hopefully produce in the region of 300-310bhp, but do you think the extra oomph of a td05-16g billet, for example, would make it faster on a typical track? brands is my closest track, and when i had my non-billet 20g it was somewhat annoying to have lag in the corners (e.g. coming out of druids, there'd definitely be some delay between putting your foot down and the turbo responding). Could it be the case that a smaller turbo with less power would actually be faster? :)