I was just trying to see if anyone had any input on some modifications that would further increase the fuel mileage of a 1st gen.

It seems like the "TAG" product has had a good bit of sucess in doing this, among other things, and it is surely one my first things on my "to do list," but I was wanting to know if there were other mods I could do also (Short of the $2500 Dollar add on overdrive units on the market).

 

Advancing the timing, going to a smaller turbine housing, and freer flowing air filter and exhaust are all I can think of, and I'd do them in that order. The TAG is held in by the silencer ring snap ring that the HX and HY turbos use, so it's not easily applicable to the H1C on your truck.

 

How about going to synthetic oils in everything, tires at max inflation, make sure the front end is aligned and it tracks straight. Also, to get nitpicky, reduce the weight- i.e. don't pack around your anvil collection! I used to get people complaining about their VW bugs getting 'bad mileage'. Open up the trunk and you have 6 bags of cat litter for traction, a 20 ton bottle jack, a tow chain made from the anchor chain off a battleship and enough tools & spare parts to rebuild the space shuttle!! Last but not least, a good wax job to cut wind resistance. A bunch of little things that add up to one big thing! Jim