@shyber
Hooking it up in July on CNG.
It can be done, you just need to know the proper people to do it.
Already have a Starlet GT with a friend (actually the person who is going to do the CNG setup, his car has a 1300cc intercooled turbo a nice intake and a free flow exhaust) running on CNG. That thing is fast, I tried catching up to it in a 2001 City (my own, petrol, runs beautifully) ... had no chance whatsoever to catch up.
Common misconception that a better intake worsens mileage. It improves it. Your car performs better, means u have to push it less to get a certain speed. Means more fuel economy.
When people get exahusts n intakes they keep pushing the car more and get crappy mileage.
And with a feather foot on the pedal, that turbo doesnt spool ... no boost (confirmed via guage), no extra fuel ...