why can't we use one of these turbos?
 

We can.
But we don't. At least that I've see.
Why? Because t$$xas and because they often fail, so more t$$xas

You can solve this even cheaper: go buy a Holset variable geometry turbo like the HE341VE. Sure it's a 40lb turbo, and will need to be a custom top-mount setup, but who cares when it will make 55 pounds of positive manifold pressure amirite?

a few people ran the aerodyne, which was prone to failure. i wasnt impressed by dynos.

another ran the VNT25 or GT22V -- remotely and it performed terribly.

Variable geometry turbos are popular on diesels because they have much lower EGTs than gas motors, so the variable stuff can actually survive a reaonable amount of time.

--Ian

That makes a lot of sense. Also, I read that another trick that porsche uses to reduce lag is to briefly lean the mixture as the engine starts into boost. Any tuners able to pull this off with MS? Or, is it too risky?

Everyone and their mother has done/tried this. It doesn't help nearly enough to be worth running the engine lean

Neg Cats for (me) restating crap.
But folks have tried VNT turbos for decades in the motorcycle and car world. It never works. the exhaust gas temps are too high in a gas engine. Don't bother. Buy a modern turbo and forget this forever please!

Thanks for setting me straight. I've been spending way too much time at the dealer getting my car fixed... nothing to do but read up on the hot new models. Apparently, this is more "marketing" than a "performance upgrade". Just what Porsche needs is more reliability problems...

The exhaust temps too high thing was correct in the 80's. All the new tech handles 1600* easily.

*f ?

1600*f is just where the fun starts. I get near 1500*f with just 160kpa on the track. Others see 1800*f sustained.

https://cimg8.ibsrv.net/gimg/www.mia...e0f5e868dd.png

This is my audi's turbo and downpipe after 1-2 minute of first gear "drifting" in the snow recently. Doesn't take much to get things hot in a turbo car.. Rip k03s