131 fuel economy

[Robert]

I know that Fiats are no fuel wasters. Nevertheless I was stunned by the (relatively) low fuel consumption of my car during the 3MA meeting. On the way from Kingsteignton to Dover, doing a moderate speed of 60-70 mph (100-120 km/h), the car took a meagre 7.6 l/100 km (equals to 37 mpg). Not bad for double Webers that are still not properly tuned  . 

[bellamacchina]

For sure your car uses much less fuel than mine

[jasonh131]

As i said on the main 3ma thread ,jade did 26 mpg and his 3526 mile trip.
 and i poodled down to the hotel at 50 mph and got 45 to the gallon  , not so on the outings or on the way back.

[mirafioriman]

Are you sre your calculations are correct? I would have thought a standard 2 litre 131 would struggle to do 37 to the gallon.

[jasonh131]

Yes its possible, a much modifyed 131 produce 's more power at a specific rev s say 2000revs at 60 mph in standard form ,so a modified one needs less revs to go the same speed .
 if you can resit the urge and poodle a a very small throttle
response ....its very hard  

[Robert]

420 km distance, filled in 32 litres of fuel. I'm doing fuel calculations for more than 30 years now, so I assume this is correct. Am astonished myself. Nearly perfect conditions, not much braking and 99% of the distance in 5th gear.

On the outings, fuel consumption was higher, but never exceeded 10 l/100 km. I do know, however, that with the old setup the car took on rallye stages around 15 l/100 km.

[Tas131]

Yes its possible, a much modifyed 131 produce 's more power at a specific rev s say 2000revs at 60 mph in standard form ,so a modified one needs less revs to go the same speed .

It still requires the same engine revs to do the same speed unless you've changed the gearing. The engine may produce more torque in that rev range, and hence require less throttle to hold the car at that speed.

My 2 litre with twin 40 IDFs used 10.5l/100km consistently. I never had any long trips with it though. Mostly to and from work, a 37km round trip. It now uses between 13 and 15l/100km of LPG, but it's still cheaper than running on petrol.

[longhamrob]

Remember the 131 speedo overreads probably at least 10%. They reported that on a road test in that era.  If you have lower profile tyres than original if will overread even more. Your speedo is telling you that you have travelled more miles than you have done, quite a lot on a tankfull and will knock a noticeable few mpg off.... I check my mpg on every fill up of my 131R. With  twin 44idfs, i average 24mpg less the speedo correction making it nearer 22mpg.