Just a quick question!!

Now don't get me wrong, I had no illusions that my STi was going to be good on the juice but what is the ideal cruising speed on the motorway for one? Its a 1999 Import STi. I only ask because my Integrales used to be rubbish unless I did around 85mph, 70mph and they were really thirsty for some reason!! Sounds strange, but I did own 3 and they were all the same!!
I am not after any sarky replies please just average nice speed to drive on the motorway thats least thirsty. (and I don't drive moon miles by any means before anyone suggests buying a diesel)
Aslo, is it right to get around 22mpg around town (bit of a squirt now and then!)

Thanks guys (and gals!)

 

I think its been proven that 85 gives better fuel economy over 70 actually!!!

I get 22mpg round town in a uk ppp.

 

22 sounds good for around town.

 

Motorway ..... 56MPH apparently??

Pete

 

Pete, do not sit at a constant 56! The airbox resonates at that speed and disrupts the flow across the MAF, it can be fatal. aparently you can buy a gauge to monitor this though.

Mark.

 

Oh!! Fooooooooooooooooook!! Thats my MAF knackered

I thought I was getting 36MPG because I was driving careful ...... it's the MAF thats running the Engine weak!!

Bugger, Bugger, Bugger off to my local Boxer Engine re-builders to get spanked with a £2000 bill!!

Thats if I can get in!! They are swamped by blown Engines!!

Why, oh why, don't owners take the plugs out before they start these cars after a nights oil drain down!! makes me mad, I'll have to wait now!

Pete

 

 

LOL @ Pete

 

It's amazing how many people think 56mph is the best economy speed for all cars, just 'cos the mpg figures used to be given at that speed.
Would've thought an 'engineer' would know better...

I'd guess (simplly put) it's a combination of highest gear, being at the rev range with the most torque but taking wind resistance into effect too.

 

One benefit of our chocolate alloy engines is that a high proportion can be recycled into easter eggs.

 

In the days when mpg was measured at 56, rather than the extra-urban etc, ECU's were set to provide economy at theat speed, to push the figures up. Just like the stange half-boost issues in 2nd.

Mind you, test have shown manufacturer's figures (calculated by bench testing, not actually driving a car), are generally 20-30% optimisic.

I get around 15mpg in my Classic, just can't face driving it efficiently!

 

PMSL ......... havent heard anything as funny as this in ages

 

In most cases 56MPH is the most efficient speed to cruise at, it was explained to me in an engineering class once, it is carried on with airoplanes, with the most economical speed happens to be around 560MPH.

I have however forgotten the details, as you do.

 

Thanks to all the replies. Think I'll just drive at 150mph then I'll get there quicker and won't have as long to use all my fuel up on a long winded drive......ha ha ha. What do you think to my logic?? Sounds like woman logic!!!! If i'm on the road less time I won't use as much fuel........hmmmm the kind of thing my girlfriend would say!!!

 

Having driven a Focus RS about for the past 2 years, I never reached above 20mpg. Usually averaging about 18-19mpg. 12mpg pushing on a bit. About to take delivery of my new STi UK PPP. I'm expecting the Focus to seem positively econimical compared to the Sti. At the end of the day though, I've bought it for one reason....... to go as fast as possible. Sod the fuel costs. Just hope I feel the same in 6 months time.

Stilover

 

Oh, it's nice to remember that old chesnut being trotted out back in the golden 1970's - when 40MPG was considered the height of economy and only from the most frugal car. 56MPH may still be the optimum, but with engine technology moving on and the Impreza being a more powerful car, it's probably most economical at say 70-80 MPH. I seem to remember reading somewhere not that long back that big cars like Jaguars are more economical at higher speeds.

 

Eeee.... it must be at least a week since we had a fuel economy thread...

Them were 't'days......

 

...the number of scoobies ive seen at a steady 56 on the motorway..

...having said that as long as your off boost and below the speed-limit icant see you can do anything more.... .But what a pisser to blip the throttle between 80 an 90 and be getting <20 mph while MR 2 litre bmw is getting twice that.

 

On the MY04 STI setting the rev limiter at 2500 on the motorway will see 28mpg and at 3000 it will return 25mpg. Providing your speed is constant even 100 will see 20 to 22mpg.

What seems to kill the mpg is acceleration (obvious really). Nothing like diving down your favourite B road emerging 5 mins later with the fuel guage having visably moved. If you floor the loud pedal everywhere it is easy to drop the MPG to 12 - 14 on the road. On the track down into single figures.

 

Well I'm getting 36mpg now ......................

I must have a record breaking Impreza ... the brake pads are STILL standard after 56,500miles - I'm starting to wonder about it??

Pete

 

....im sure you have pete