Things that helped my turbo Raider fuel economy:

The air temp sensor in the MAF had a poor solder joint resulting in a higher resistance and poor fuel metering. Test it and repair as needed.

An old O2 sensor that did not read right.

A poor connection on the intake manifold temp sensor.

A worn dist with a bad vacuum advance mechanism. The wear was in the bushing area where the advance plate rotates on the main shaft. It was loose and egg shaped right at cruise rpm. This caused spark scatter and poor ignition.

Factory alignment setting at maximum camber gave high rolling resistance with big tires. Resetting it to near 0 and upping the pressure helped a lot.

A down pipe that eliminates the front conveter, less back pressure = better throttle response and better fuel economy. This is a great modification, the difference in torque is amazing. I posted pictures on this a while ago, you might be able to find it doing a search.

A hollowed front converter helps but the section that bolts to the turbo needs porting, nasty bend. My second converter is a larger high flow unit.

A lockup torque converter for my auto, this added an easy 2+ mpg on the highway.

I went from 13 mpg on the highway to 20 or so at speeds a bit over 70, 75 mph typically. The engine also throws off a lot less heat and runs cooler now.

Kevin C