A cheap chip

[Marajin]

Assuming you live in a country that allows those things ..

If your looking at a proper de-mande then do it right so that you don't have to look back in 6 months or a year wishing you had while sitting on the side of the road with a popped turbo or engine.

Your options are>

Unilevers, Gearherad in maryland, or Mr. Hag down in atlanta.

if you have a 871 engine you can do it yourself using instructions for MM off the internet. Guys who are decent with a computer get brave and do their own with good success.