RPM's at 65 mph.

[Mudnut]

I am waiting until they sell the Mustang down in Australia. I am considering all options, as I have a 150k round trip commute . I usually set the cruise control to 105 kph (roughly 65mph) once I am up the mountain range, to avoid radar traps, and kangaroos. 100 kph speed limit down here. My current car JCW MINI sits on about 2800 rpm in 6th gear. I currently get around 7.8 - 8 litres per 100k.

What I am looking for is rpm's for the GT with PP: ? fuel consumption

GT Auto: ? fuel consumption

Eco Boost PP: ? fuel consumption.

This will give me a rough idea what the car will use, and I can factor in if it is justifiable in getting the GT vs the Eco Boost to SHMBO (She Who Must Be Obeyed).

Cheers,

Ken

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[Old 5 Oh]

I am waiting until they sell the Mustang down in Australia. I am considering all options, as I have a 150k round trip commute . I usually set the cruise control to 105 kph (roughly 65mph) once I am up the mountain range, to avoid radar traps, and kangaroos. 100 kph speed limit down here. My current car JCW MINI sits on about 2800 rpm in 6th gear. I currently get around 7.8 - 8 litres per 100k.

What I am looking for is rpm's for the GT with PP: ? fuel consumption

GT Auto: ? fuel consumption

Eco Boost PP: ? fuel consumption.

This will give me a rough idea what the car will use, and I can factor in if it is justifiable in getting the GT vs the Eco Boost to SHMBO (She Who Must Be Obeyed).

Cheers,

Ken

GT PP is going to be about 2,100 RPM at 65. GT AT with 3.15 gears will be closer to 1,800 or a little less.

Guys are reporting 25 mpg and better for PPs at that speed, even more for non-PP GTs. EBs are seeing over 30 mpg. Sorry, you can convert to l/100k. :frusty:

 

[JoeDogInKC]

GT PP is going to be about 2,100 RPM at 65. GT AT with 3.15 gears will be closer to 1,800 or a little less.

Guys are reporting 25 mpg and better for PPs at that speed, even more for non-PP GTs. EBs are seeing over 30 mpg. Sorry, you can convert to l/100k. :frusty:

My GT + PP is just under 2000 rpm at 65. Probably around 1950 or so. At 75 -80 though, it's closer to 2500 rpm.

 

[Shark77]

The math on it is this:

Assumptions:
Rear tire diameter: 27.7in (between tire options this could vary rpm +/- 30 rpm at 65mph due to diameter differences)
Manual 6th Gear: 0.651
Auto 6th Gear: 0.69

RPM at 65mph for final drive

Manual
3.31: 1700rpm
3.55: 1820rpm
3.73: 1910rpm

Auto
3.15: 1715rpm
3.55: 1930rpm

 

[Mudnut]

Thanks for the replies.
Just had to google mpg to litres / 100 km


Conversion Table
10 US M.P.G. = 23.522 Litres / 100 km
15 = 15.681
20 = 11.761
25 = 9.409
30 = 7.841
35 = 6.721
40 = 5.881
45 = 5.227

So the GT is roughly 2l / 100 km more, or about $3.50 extra for fuel over here. Strong argument for getting GT over the Eco Boost, not to mention the sound of that sweet V8

Cheers,

Ken

 

[Colleton]

My GT+PP was dead on 2K with the cruise set on 65mph.

 

[Old 5 Oh]

The math on it is this:

Assumptions:
Rear tire diameter: 27.7in (between tire options this could vary rpm +/- 30 rpm at 65mph due to diameter differences)
Manual 6th Gear: 0.651
Auto 6th Gear: 0.69

RPM at 65mph for final drive

Manual
3.31: 1700rpm
3.55: 1820rpm
3.73: 1910rpm

Auto
3.15: 1715rpm
3.55: 1930rpm

Forgot about factoring in the taller tires! Now a 3.73 behaves just like a 3.55 did on the old standard 25.5 inch tires. And the 3.15 is really pretty high. Good thing the AT has such a deep first gear!

 

[1320']

I am waiting until they sell the Mustang down in Australia. I am considering all options, as I have a 150k round trip commute . I usually set the cruise control to 105 kph (roughly 65mph) once I am up the mountain range, to avoid radar traps, and kangaroos.

I know it's a real problem..but that made me laugh way more than it should have.

 

[Shark77]

Forgot about factoring in the taller tires! Now a 3.73 behaves just like a 3.55 did on the old standard 25.5 inch tires. And the 3.15 is really pretty high. Good thing the AT has such a deep first gear!

I based it on the GT PP rear tire 27.7 inch.

 

[JimmyTwoTimes]

The math on it is this:

Assumptions:
Rear tire diameter: 27.7in (between tire options this could vary rpm +/- 30 rpm at 65mph due to diameter differences)
Manual 6th Gear: 0.651
Auto 6th Gear: 0.69

RPM at 65mph for final drive

Manual
3.31: 1700rpm
3.55: 1820rpm
3.73: 1910rpm

Auto
3.15: 1715rpm
3.55: 1930rpm

... WOW.

Jeez, I am SERIOUSLY going to miss the 2.73:1 final drive on my current Mustang. At 65 mph, I'm at about 1300 rpm. I can't imagine how bad the engine will be straining at 1715 rpm for long stretches... I mean, I can see getting that high in short bursts coming out of a red light or something, but on a long highway cruise? Jeez.

 

[Mudnut]

I know it's a real problem..but that made me laugh way more than it should have.

Well I hit a Roo on the way home from work tonight. Fortunately I was in the Land Rover Defender, and not the MINI.

No damage to the car. (Bull Bar) Roo was dead before it hit the road.

As interesting as they are, they are really stupid. This one was the size of a large Labrador. Jumped right in front of me, with about a second to spare.
Fortunately no one in the oncoming lane, when it bounced off my car, as it would have gone through the windscreen.

Cheers,

Ken

 

[oyitsagreen]

... WOW.





Jeez, I am SERIOUSLY going to miss the 2.73:1 final drive on my current Mustang. At 65 mph, I'm at about 1300 rpm. I can't imagine how bad the engine will be straining at 1715 rpm for long stretches... I mean, I can see getting that high in short bursts coming out of a red light or something, but on a long highway cruise? Jeez.

1715 RPM is cake for the engine. They are designed to be safely operated up until redline.

 

[SVTFreak]

I know when I was in Oz on vacation, I was amazed at the number of Roos. They are worse than the deer down here (up here to you Aussies).

I was going to tell you what I get in my auto pp gt but someone broke it down for you. What they've calculated is correct and highway at 65, my computer shows 24-26 depending on a few factors. I haven't ran it like that long distance yet but it should extrapolate.

 

[Keyser_Soze]

1715 RPM is cake for the engine. They are designed to be safely operated up until redline.

I think he's talking about mileage, and possibly about exhaust drone at higher RPM's if he goes aftermarket. I'm sure if you take the same Mustang and applied 3.73 gears vs 3.15 gears and tested them at 75 mph, the .15 would come out far ahead in mileage due to the lower RPM's.

As a general question, can anyone chime in on RPM's contribution to gas mileage on these 5.0 V8's? Big difference between the 3.31 and 3.73, given identical external circumstances?

 

[foghat]

... WOW.

Jeez, I am SERIOUSLY going to miss the 2.73:1 final drive on my current Mustang. At 65 mph, I'm at about 1300 rpm. I can't imagine how bad the engine will be straining at 1715 rpm for long stretches... I mean, I can see getting that high in short bursts coming out of a red light or something, but on a long highway cruise? Jeez.

:frusty:

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