Thread: e10,91,95,98 for d2 v8

Don't think 98ron was widely available back then but 98is 98 and 95 is 95 Ron , (research octane number) . d2 v8s don't have high enough compression to take advantage of 98 in standard guise
Regarding measuring differences with gauge.... You wouldn't get even close to accurate
Cheers

personally i find i get further on a tank of 98.
it may cost more, but i feel its worthwhile.

ive done three tankfulls since aquiring my D2 V8 and decided right off the batt to work out if there is any differnce between 95 and 98

Both tanks have been similar routes - about 180 km a day back and forth to work, combination of a little city traffic and mostly highway diriving.

First tank was 95 ron and avg 16.3l/100
Second refill was on 98 ron, and came in at 16.2L/100
On my second refill i put 87 litres in - so not much 95 left in the tank to water the 98 down.

taking what could be traffic variables into account, i dont think theres any economy benefit to runnig 98

There is no way you will see an economy benefit % which exceeds the price difference % in a Low compression RV8 even with Motronic as it will be tuned to run on 91.

If you are lucky enough to have one of the last D2As with a High compression v8, you may see a benefit as the timing will be optimized for 98 and using 95 will knock back the advance, but it is doubtful that the % increase in economy will exceed the % difference in price.

An extremely dirty carboned up V8 will see a better increase, but probably an Italian tune up will do the same thing.

Regards Philip A

Originally Posted by PhilipA

If you are lucky enough to have one of the last D2As with a High compression v8, you may see a benefit as the timing will be optimized for 98 and using 95 will knock back the advance, but it is doubtful that the % increase in economy will exceed the % difference in price.

actually my D2 (not D2A), is a high compression v8.

High compression v8 in d2 is relative, cars that can use the 98ron are usually running 11.5 or higher compression ratio, the knock sensors (piezo electric microphones)on d2 won't tell the ecu to advance the timing any further from 95ron to 98ron therefore any benefit is less than negligible, but if your happy paying the extra for the placebo effect then you won't do any damage

that would be true if timing advance was the only thing 98 was good for.

Originally Posted by Eevo

that would be true if timing advance was the only thing 98 was good for.

It is a scary day when I find myself in total agreement with you Eevo