I have been contemplating going into the 400+ bhp club for a while now, seen as I'm fully forged, and I'm on the brink of doing it, but have a slight dilemma.

I want to be comfortably in the 400 bhp and want to keep lag to a minimum, but should I just be done with it and go for GT3071?
There are so many different specs and trims and variations, and having a chat with Flea the other day and he said the lag between a GT2871r and a GT3071 will be minimal.
But the nature of a bigger turbo is going to be more laggy right?

What do I do..........

you'll suffer more lag by going for the larger turbine AR - a 0.86AR housing will be at least 500rpm behind a 0.64AR

For this reason, I'd recommend a 3071 with a 0.64AR turbine housing. It should only be a tiny bit laggier than a 2871 with 0.64AR

The 2871 will give 400bhp, but its nearing its upper limits and you'll need plenty of other supporting mods to extract the best from it

Mate, empty your inbox!

Done.