I don't know if the 1.6 will compete with what it will run against but it will be fun to try. I have to run against 2.3 turbo Fords, one has twin Honda goldwing motors on alcohol, another has two big snowmobile engines and stuff like that. I can run up to a 2.4 diesel and two turbos if I want but I got a deal on two 1.6 VW's so I am going to try one. Going to port the heck out of a 1.6 head and see if it works. want to go to a T3-T4 hybred at some time also. Thinking of trying a inline pump if I can find a deal on one. Its a low budget project.
My original plan was a D24 but they are hard to find in my area of the country. At least I could not come up with any.
You pulling tractor guys really amaze me. I have a friend running Bolens bodywork on a custom frame about the same size as yours with a gas turbine. Make smoke!!!
I do have a good TO4 turbo off a larger diesel engine with a 2" inlet but I have no idea if there is a small enough exhaust housing for it so a 1.6 would spin it. I am looking for a used TO3 so I can make a T3/T4 turbo.