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Old 03-25-2014, 08:38 PM   #5 (permalink)
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xecute's Avatar
Join Date: Feb 2013
Location: Dunedin, 9010 NEW ZEALAND
Posts: 21

ITZOLD - '81 Ford Mustang L
90 day: 15.44 mpg (US)
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Originally Posted by MetroMPG View Post
How did I miss this intro thread?

A belated welcome to you, xecute.

Sorry for an obvious question: with the amount of driving you do, was fuel economy not more of a priority in vehicle selection?

Clearly you enjoy the Mustang; maybe that's all that matters!

I needed something serviceable, LHD, American, able to be ecomodded. It was the only alternative to either the 98 Explorer, or a 1996 NZ market Taurus.

The average cold running city figure of 10.3 US mpg in San Francisco like hills of Dunedin, open road warm running best of 17 mpg at 62 mph average open road speed, but normally 53 to 73 mph due to traffic flows and grades of up to +/-12%. My overall average is therefore 13.7 mpg vs. the 22 US mpg ideal for the LA basin test.

New Zealand is a totally different kettle of fish, with coarse high friction chip seal with a soft structural number (flexible with high deflections under load), very sharp relief with overall average climbs of +4% common to audits, then -4% downgrades on return. It's rare to get dead flat conditions. Automatic transmissions, and road conditions and traffic densities on two lane undivided center line roads make it very, very hard to practice moderation in driving.
I've been very busy with road inspection and other work. I've used a 1.6 liter 1992 Mitsubishi Galant sedan and my dads old Camry style Front drive Central Fuel Injection Corona 1832 cc sedan, and not gotten better than US 22.4 MPG with my standard 780 mile monthly inspection on coarse chip seal with 3300 feet rises over 90 miles being the common theme. And with a tight dead line for completion, I cannot be gentle with the throttle or drop below a 50 mph average speed for 16 hours driving. Always two lane, undivided centreline, behind trucks and caper vans and tourists.
US mpg Figures for the G spec 170 hp 4 speed auto RAV4.1's were 16.2/28.2/22.2, and the 5 speed 205 hp Explorer was 15.2/22.6/18.9.
In US mpg, best 523 mile G spec 170 hp 4 speed auto RAV4.1 average was 29.3 mpg at 62 mph average. Around town, 17.7 mpg

With the XLT 98 Explorer, a fully US compliant vehicle, the best open road figure was 29.3 mpg also, but 21.65 was common open road, 16.7 mpg town.

When the bluff 3.5" wide export guard flares were removed, the 265 /70 16's replaced with 235/60 16's M&S, I got 23.35 average open road, and 17.7 us mpg around town.

The road conditions are probably like a combination of Idaho and some parts of Southern California's coastal roads. Its worse, we have two lane blacktop, and I have an audit schedule which has been the same since 2010 to date, which means I am totally time bound to cover the miles in the same time-frame, at the same average speed. There are no slip lanes, no options to reduce speed, and therefore compared to the US Highway figures, the 92 hp 3.3 six is much harder worked than the two SUV's.

I was up to 15.44 after practicing moderation, but it hurt my arrival times, with average speed dropping 10 mph over a 780 mile audit, it cost me 2 hours and 20 minutes in total, plus safety issues with traffic flow where I use video camera evidence.

Performance is a partial issue. I'm also truck driver, so its nothing for a loaded semi taking a 300 hp 50 ton weight to less than a 44 second 1/4 mile, roughly equal to a traction limited 3300HP G Class loco weighing 127 tons. Though I can't really enjoy a 20 second quarter mile car, its acceleration isn't an issue except that it won't go up a 12% grade at 60 mph without 100% throttle. My old SUV's didn't really suffer like the Mustang does, but its got very little total cdA aero drag compared to those SUV's I've used.

At least the Stang is 4 seconds faster than the best race horse over the 660 dash...

My set amount of work means my only option to reduced fuel consumption is aero and engine efficiency. The average speed won't improve much with any coast down reduction or power gain..

Last edited by xecute; 03-25-2014 at 09:28 PM..
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