Join Date: Jan 2008
Location: Tunbridge Wells
I had, until recently, a diesel performance / economy chip fitted which boosted my BHP from 150 to 170. Although it could, theoretically boost economy with less need for heavy acceleration to get up to speed and maintain it, I found myself using the extra power all the time so MPG dropped to around 42 MPG on a regular 130 mile round trip daily commute on the M25 and major A roads.
Having removed the chip (which incidentally lowered my insurance by around £150), economy has returned to around 48-50 MPG based on a manual calculation rather than the trip computer. The computer is unreliable and gives a better reading than is the case e.g. 56 MPG v 50 MPG actual average consumption. I have an '54 reg GT.
Alfa Romeo GT Cloverleaf Q2 170bhp
Alfa Romeo 159 Sportwagon TI Q4 210bhp