I've been running a test on a 10% solution of veg.oil derived fuel in mineral diesel over the last few months.
At the time, mineral diesel was £1:40 per litre, the veg.oil was £1:09 per litre.
The test was brim-brim for fuel consumption, personal estimate for everything else.
As far as I could ascertain, the transesterification process was the same as would be performed by an amateur. Information on cloud point was given by the supplier.
The results were as follows:-
No difference in performance was noticed, but the engine micro. noticed as there was a brief flash of the mil. lamp after starting when the mixture reached 10%.
There was a faint whiff of veg.oil from the tail pipes.
There was a degradation in fuel consumption by about 3 to 5 mpgUK.

Conclusion: There was no advantage in using veg.oil at this price. Also the vehicle handbook advises in heavy type AGAINST using veg.oil at more than a 5% solution in mineral diesel. As far as I know, there is ATM a 3% solution from the pumps in UK, prob. to help lubrication of the car's injector pump with the low-sulphur diesel.
It would seem then that bio-diesel has the same problem as bio-petrol (ethanol and methanol). There is a fall off in fuel burning efficiency.

I would imagine if you're using bio-diesel in an old engine of the passive injector type, you're making it yourself, and you live in a warm country, there would be no reason not to carry on.

Leedsman.

 

what you say is true about bio-diesel fuels.

i run bioD in my Opel Isuzu coupe,1.8L, but i get my Veg oil for FREE ,and i mix it 50-50%, so my money saving for the year is very low,like 50%.

yes its old tech mechanical injection, but bio has plenty of lube in it.

and true it doesnt have as much power,BUT it aint no race car anyway, not with only 1.8L. but i'm close to 50mpg on a US gallon. and it is warm in texas(most of the time)!

some place on this site there is a diesel Ford Mustang, check out , google diesel mustang, texas mile. i seen the car run and just shows the potential of a Ford with a GM diesel in it.

course i got a Jaguar also, V12, i like cars,all kinds.

 

i do believe USA diesel fuel has been upgraded,in just the last 6 months, the old deisel smell is almost non exsistent, and smoke, on mine is non exsisent also, power is up.

makes me happy! altho not happy with the cost.