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[Skylarking]

Since this is a fuelly thread ... I had the old project car pink-slipped today, was talking to my mechanic about the stuck IAC, and he initially thought the problem might be fuel.

He said 98 is really unstable & only lasts a month before getting dodgy ... he reckons 95 is nowhere near as unstable, and that if you go for a drive before the car's going to be parked for some time you should try & use as much as possible of your 98 & put at least a half-tank of 95 in for when it's sitting there. He also reckons never use 98 for mowers, whippersnippers etc for the same reason.

Hm, don’t know but isn’t 98RON a more refined fuel grade which contains more volatile components as compared to 91RON? I‘m not a chemical engineer working in the petrochemical industry so can’t say, but if that’s so, it seems logical to accept how the more refined volatile compounds would be the first to evaporate, since they are more volatile. As such, I‘d think 98 would have a shorter shelf life than say 91. And just like radioactive decay, wouldn’t that mean if 98 looses its aromatics or other volatile compounds, then what’s left behind may be something that is more akin to 91?

Whatever the case, old fuel ain’t as good as new fuel. However, I must also confess I haven’t had issues with either 98 or 91 in my lawnmowers (I have two, a 2 stroke and a 4 stroke). I just use whatever is convenient on the day I fill up the 5ltr can and it lasts me many months

 

[[paradox]]

Just went for a big cruise yesterday ~300km each way
average fuel use got down to 8.6L, travelling at 110. Nice. Never really payed attention to it before.

I think the best i got out of my VE was 9.1L

 

[figjam]

He said 98 is really unstable & only lasts a month before getting dodgy ... He also reckons never use 98 for mowers, whippersnippers etc for the same reason.

........... and yet I have been told by the local mower and garden tool retailer, who has been in the business for 40 years, to use 98 as it lasts longer in a sealed container, and don't use E10 as it gums up the carby when the motor is not used for a long period.
The truth must be out there somewhere.

 

[mpower]

........... and yet I have been told by the local mower and garden tool retailer, who has been in the business for 40 years, to use 98 as it lasts longer in a sealed container, and don't use E10 as it gums up the carby when the motor is not used for a long period.
The truth must be out there somewhere.

i think it's in a pudding.

 

[kleanphil]

I just finished a tank of E10 and got 582km on 69.5L , i was a bit surprised as highway traffic was stop go for atleast 5 to 10 min each morning and a few days in the arvo . I just filled it again with E10 and will see how this tank goes . i think the jobs are a bit closer this week which seems to use more fuel as the highway klm's are a lot less

EDIT: I was doing 128k's a day there and back with about 25km done on local traffic roads for 3 days , a trip to the shopping centre 1 day and 1 day 128km's there and back and a one way trip of 64k's with 6 k's on local roads .

EDIT AGAIN : I thought i might have made a mistake so i checked my distances on google maps and according to that i did 604km's which did my head in , i think i need KIT-KAT !!

The discrepancy between google maps and the odometer i believe is because of tyre size as i have 35 profile and i think standard for my rims is 30 profile so it may be closer to the 600k which is not bad concidering the shitty highway traffic i copped. i'm pretty sure thats the way it would go with the bigger tyre .

 

[Batca]

Since this is a fuelly thread ... I had the old project car pink-slipped today, was talking to my mechanic about the stuck IAC, and he initially thought the problem might be fuel.

He said 98 is really unstable & only lasts a month before getting dodgy ... he reckons 95 is nowhere near as unstable, and that if you go for a drive before the car's going to be parked for some time you should try & use as much as possible of your 98 & put at least a half-tank of 95 in for when it's sitting there. He also reckons never use 98 for mowers, whippersnippers etc for the same reason.

My marine mechanic when I owned my boat said similar . He advised just fill it with 91 as it would sit for periods of time (Merc optimax 2 stroke)
I only use 91 in my mower chainsaw etc but add a bit of stabiliser to it in the jerry can if it will store for a while

 

[Big Red VF-SII Go-kart]

Just went for a big cruise yesterday ~300km each way
average fuel use got down to 8.6L, travelling at 110. Nice. Never really payed attention to it before.

I think the best i got out of my VE was 9.1L

If it's a V8, this figure is plausible, but you have to ask, on a 300 x 2 trip on the open road, can it do better? On PULP98, I think so.
The speed gain from 100 to 110km/h should not trouble either the V6 or V8: it is literally free-pedalling.
The V6 SiDi running PULP98 can burble along at 3.9L/100 over a 440km one way trip on the freeway. Surely a V8 can get down to at least 6 to 7.5L?

 

[J_D 2.0]

If it's a V8, this figure is plausible, but you have to ask, on a 300 x 2 trip on the open road, can it do better? On PULP98, I think so.
The speed gain from 100 to 110km/h should not trouble either the V6 or V8: it is literally free-pedalling.
The V6 SiDi running PULP98 can burble along at 3.9L/100 over a 440km one way trip on the freeway. Surely a V8 can get down to at least 6 to 7.5L?

If the V8 was doing 8.6L/100km on the highway on 91RON it would need to get down to 6.88L/100km just to break even on the fuel costs. I would think it would be difficult to get down that low with a V8.

My VE V8 manual is lucky to get below tens running on 98RON cruising on the highway (when I’m not running it on LPG that is). Admittedly my SSV has extractors, 2.5 inch twin exhausts, CAI and is dyno tuned to run on 98RON so would be biased toward power rather than economy but still...

 

[Forg]

Y'know, I'd expect that exhaust & intake mods plus a tune to suit high-octane fuel, yet without cam changes etc, should actually improve fuel-economy c/f a standard car being used in a similar low-load way. Assuming an optimal tune, I guess, which could be a big assumption.

 

[J_D 2.0]

Y'know, I'd expect that exhaust & intake mods plus a tune to suit high-octane fuel, yet without cam changes etc, should actually improve fuel-economy c/f a standard car being used in a similar low-load way. Assuming an optimal tune, I guess, which could be a big assumption.

I would expect so but seeing as I didn’t get the tune done (was done by the dealership as part of the dealer upgrade package when it was new, along with all the other mods) I don’t know what parameters it was tuned for.

Seeing as it still had the Holden factory warranty off the new car lot with the tune I expect that it would be quite conservative and err on the side of caution (over fuelling) to protect the factory warranty.