Has anyone noticed an increase in fuel consumption when replacing the factory fit tyres to F1’s? This question has been posed on another forum. The car is a MK2.5 1.6, the author reckons his car went from 38 mph to 32 mph after the swap.
No, nothing of the kind. Must be something else.
If the figures are accurate, that’s a 15% drop in economy, which is pretty severe. I don’t suppose there’s any chance he fitted the wrong size of tyre?
I would suspect that the new tyres are not inflated correctly, and is causing drag, or possibly that whilst removing the wheels (or possibly fitting them), so much force has been used (possible because airguns were used before), that the suspension geometry has been knocked off, again, causing excess drag.
Tyres can make a difference, but unless he had economy tyres before (and even then…) there is no way that the tyres alone made that big a difference.
The cold weather at this time of year can badly impact fuel economy (not usually that much), especially if you are starting your car to de-frost it (1500RPM for 5-10 minutes, and no miles travelled)
Thanks for the replies. I suggested to the owner that his handbrake was maladjusted or his driving habits had change but he insists that the only change has been fitting F1’s. Would fitting them the wrong way round affect mpg (as well as handling) ie the arrow pointing backwards?
I have a MK2.5 1.6 and get in the region of 38 mph on F1’s. Maybe I’ll switch tyre brand next time and get a 15% improvement in MPG[:)]
I’m a sad anorak who keeps a spread sheet of all my motoring stuff including petrol/mpg etc. I changed to Eagle F1s about 3 months ago and the petrol consumption is still a pretty flat line
I too keep all petrol records on a spreadsheet. My wife’s 2002 1.8i Sport:
First 3 years (21,000 miles, factory tyres) 30.44 MPG; next 3 years (23,000 miles, F1 tyres) 30.20 MPG. Changing to F1s didn’t affect MPG.
Thank you all for yr replies which confirm that F1’s do not adversely affect mpg. I will refer the correspondent on the other MX5 site to refer to your replies. If he has the courtesy to tell us what the real problem is I’ll put the answer on this thread.
re fitting them the wrong way round - no change in economy or handling, but it might aquaplane a tad more in deep water