Fuel economy on long trips

[aardvark]

Hi
After the suicidial kangaroo runied my journey 10km south of Barcaldine I limped into Longreach where the car lived for 2 months while it was being fixed. Being of strong will and mind to get to my chosen destination I hired a Commodore Omega to complete my journey to Karumba and back to Longreach b4 flying home. The one thing that did impress me was its fuel economy on the long journey. Sure I like the MPS power when I need it , but what would improve the MPS 6 fuel use on long trips.

Just asking for experiences . b4 I try and justify things to the cranky blonde

Cheers Phil

[Onyx]

Try weight reduction method before going on long cruise.

Number 1 - Lose the blonde in the passenger seat. The BOSE sound system is good enough and you can turn it off when you need some peace & quiet. Whereas the blondes, they can't.

[aardvark]

I agree the blonde doesn't have a volume knob, but I have banned her drinking in the car which does reduce the noise level

And they think mobile phones are distracting

[Doug_MPS6]

I figure my 8.5-9.5 l/100km on a long trip is pretty good, loping along at the limits in a nice tall 6th gear, with tonnes of pull available being right on the optimal turbo spool up rpm.

I have no idea what a Commode Door does in terms of fuel burn, but I doubt it's much better than this, and the MPS6 has more power, pretty much the same room, better handling and better plastic, although blondes remain optional for both.

In fact in mine there seems to be a distinct shortage of them. That particular option can get expensive! There ain't no such thing as a free lunch!

[aardvark]

Ah but some mods, like the downpipe could actually help the economy by removing restrictions on the engine. Any extra power when need would simply be an added bonus. And justifiable to the cranky blonde

Sent from my Milestone using Tapatalk

[Scaredycrow]

Kinda interested in this.

In the recent past I managed my best ever economy managing 550km on 47L of juice. For this run we had 2 ppl in the car and a weeks worth of luggage in the boot. (all told maybe 200KG of weight). Fuel was Caltex 98 octane. Maybe 50 of the KM were done off the freeway, the rest was sat at 110km/h.

How does this compare with what everyone else gets?

I'd be of the opinion that mods like an intake, DP, and ecu tune should improve overall engine efficiency, and thus save some fuel, but does it actually happen?

[Doug_MPS6]

My economy improved significantly after all my mods, despite (or maybe due to) cranking up the boost to 17psi on the Standback. The car is effortless in all phases of running at locally permitted speeds (and a bit beyond when "military boost" is required). My TPS rarely exceeds 20% as shown by the DashHawk, even on more spirited driving. My average commute burn to and from work in peak and largely stop-start traffic is 12.5 l/100km. This is usually one-up and just a few knick knacks, extinguisher and emergency gear in the boot.

[Scaredycrow]

12.5 aint great... I wonder how much you "lose" due to awd. I avg between 11 and 13 around town (13 being pushing abuot as hard as I can for the whole tank in the middle of summer).

[Watto]

I recall my best result was about 6.8l/100k on a two up trip to Kalgoorlie. Average speed just under 100km (including towns) and big tail wind. Return trip into the wind pushed this out to 7.6. Only mod was catback exhaust but I am sure that driving on the cruise control helped!

[RedDjinn]

intake/exhaust/intercooler/tune are u fuel friends for fuel eff

[Bakis]

I was averaging about 10.4 -/+ .5 litres per 100km pre tune and intake/tip and race pipe the driving is normally 10 - 5% freeway driving and 70 - 80% is stop start around town including 60km/h hilly driving rest is proper driving :P.

After all the work was done economy was 10.1/100km but this has been 1 fill up i'll keep you posted on how it goes.

I've noticed hwy cruising at 2,500rpm in 6th would give me economy of approximately 7l/100km.

[guitar69]

Before mods, my average was 10.6l/100k.
After mods (TIP, SRI, DP, BOV, Hypertech Tune, 3"CPE exhaust), average is........10.9l/100k.
Mind you, the 1st figure was averaged over 5 months, the second over 8 days. All done on BP 98ron.
Team WA just had a cruise last weekend. about 310 k's door-to-door for me. Spirited, blonde-free driving produced 9.8l/100k.
Less than your average Pov-pak Dunnydore.

Lies, damn lies, and fuel consumption figures.

[Scaredycrow]

I've noticed hwy cruising at 2,500rpm in 6th would give me economy of approximately 7l/100km.

Here lies the difference between us, my hwy cruising is between 3200 and 3500 rpm in 6th

[Nexus]

FUEL ECONOMY : On the 950Km trip from Toowoomba to bathurst I watched my calculated long-term average fuel consumption drop from 9.1l/100Km to 8.3l/100Km 580Km still with > 1/8th of a tank indicated - specifically 575Km from 47l = 8.2l/100Km (can't find receipt now, but between 45 and 47 l)

Just after manifold install....I've found I can use more around town with a lead foot, on highway some significant gains. Not certain if I can see similar gains around town - haven't tried to

The return trip from bathurst saw those averages rise from 8.3 to 8.6 L/100, however I took a route close to the range and therefore much more mountainous terrain and range crossings, and in addition toowoomba --> bathurst is on average slightly downhill, whereas bathurst to toowoomba is slightly uphill...

I expect I could see gains around town, too, but haven't been strict enough with my right foot.

[240MPS]

Here lies the difference between us, my hwy cruising is between 3200 and 3500 rpm in 6th

What speed is that doing

[Doug_MPS6]

240MPS see attmnt I made up a while back
Gear speeds chart.pdf

[Damnfuzz]

240MPS see attmnt I made up a while back
Gear speeds chart.pdf

Nerd!

I like it, that kinda research and graph building is right up my alley!

[SarcasticOne]

6 owners, correct me if im wrong, but doesnt raising the handbrake to the first notch dis-engage the rear diff, and increase fuel economy?

[lucifuge]

Using personal data from Fuelly | Share and Compare Your MPG, I always record my proportion of city to highway driving at each fill-up. Using this I built a simple model to predict fuel economy rate. It's usually accurate to within 3% or so.

Predicted fuel economy = 10L + Proportion of city driving * 4.4L.


So at either extreme my best (highway) = 10L + 0x 4.4L =10L/100km, worst (city) = 10L + 1x 4.4L =14.4L/100km.

[Bakis]

Ok with a cruise that involved a lot of hard driving and some gently hwy km and the some start stop driving I averaged 10.04l/100km which I'm happy with considering the percent of hard driving completed.