MPG of powerful engines

Dec 16, 2004 45 Replies

Reading the discussion with Sleeker about his MPG and lambda probe etc I was surprised to hear Vamp's MR2 gets "close to" 30mpg on a long cruise.



Also, Impreza WRX and Lancer Evos get really bad MPG compared to an ordinary



2.0.

If these cars are more powerful for a given cylinder capacity, then surely they are more efficient and should return better MPG when not being driven hard, whilst understandably being very thirsty when all the power and revs are being used.



I'm especially surprised at Vamp's 30mpg on a run. The car is quite light (certainly lighter than say a medium sized four door saloon) and very aerodynamic (at least to look at it you'd think so).



The best I ever got out of my Dedra Turbo was 24mpg and I drove grannified like I never drove before and the journey was mainly motorway and A roads.



Mind you, my friend with his Y10 Turbo averaged 11mpg on one tank of fuel. And that's only a 1 litre engine! Mind you that week he really enjoyed the car!



I tend to get 19-21mpg out of my car on most trips (some mway M62 nr Leeds, some town, some a road - 25 miles each way). I tend to drive with a wooooosh most of the time when moving though.

------------------------------------------------ "We are all individuals" "I'm not!"

"Carl Smith" wrote

I'm not familiar with what car you drive?

My 19 16v turbo averages 14ish MPG, i don't do many long journeys tho

The Standard 19 16v averages 20 MPG with the same driving.

Neither of which impresses me much...

03 Astra GSi 2ltr Turbo in Black.. um.. well okay in road dirt colour at the moment.

------------------------------------------------ "We are all individuals" "I'm not!"

I get around 30 from a gallon round town in the G, I wonder how low I could get it if I gave it a bit more stick. (I very very rarely get to within 2000rpm of the redline.)

Most turbo cars are less efficent off boost due to the lower compression ratio. The Evo, if i remember correcly is an exception with a comp ratio of

8.8 to 1???

I tend to get around 26mpg from mine on my normal drive which is 4 miles to work, park up all day 4 miles back from work. and the odd run here and there.

On a Mway run i get around 32-35mpg depending on traffic.

I find the 1.8T engine very good mpg wise given its performance and the weight of my tank :)

Mark Audi S3 (running chipped all the time)

Best I've had so far is 32mpg from my volvo, the temptation to make use of the turbo-torque is too great most of the time.

Mine isnt massively powerful, but driving round town i guess i'm doing about

30mpg. On a long run i've had around 40mpg. The Volvo (2.0i, not very powerful, but torquey) used to manage 25mpg with normal driving, you might touch 30 on a run.

In news:1103209607.274061327ac2806b40a48b763a18d0a9@teranews, fishman decided to enlighten our sheltered souls with a rant as follows

My old Cosworth (264 bhp per litre) averaged around 16 mpg in quick driving,

14 when caned, and an astonishing 40ish on a long, off boost run, the 4x4 Turbo Sierra (95 bhp per litre) averaged around 16 in quick driving, 10 when caned, 28ish on a run. The Merc (64 bhp per litre :-( ) gets 20ish round town, 20ish when being caned, and about 26 on a run. The Excursion (58 bhp per litre) gets 7 mpg in town, 18-20 mpg on a run. The Capri (55 bhp per litre) gets anywhere between 20 and 40 mpg depending.

i've seen mildly modded MR2's (running around 300bhp) make better mpg than my standard MR2 does! i think it's all the free flowing stuff, air intakes and exhausts that help a bit. the K&N on my MK1 gave me about 2-4 extra miles in town driving than the standard air box.

i was surprised at the MR2 could make 30mpg to be honest given the performance, i guess it's down the gear ratio's. i made 29.7 or so i think so close to 30mpg when i went from my house up to stevenage, 70 odd mile trip i think and was doing a steady 75-80mph all the way with the odd bit of boost to get past middle lane hogs.

aerodynamics of the MR2 MKII is capable of over 200mph as tested in the US during a land speed record :)

oops sorry for the top post :(

top posting! you bastard, flame him lads! and check for typo's :)

Gran Turismo could have told you that! :)

All four wheel drive Imprezas, even the cooking models, are notably inefficient - probably associated with the additional transmission losses of all wheel drive.

Perhaps. I guess it'll depend on how efficient they are when being driven less than balls out.

The ex-bosses BMW M5 could return 33 mpg on a run if he used cruise control and stuck to the speed limit. His overall average was 27 mpg, including some towing use. Actually, as I understand, there was very little difference in fuel consumption if he cruised anywhere between 50 and 100, as you'd expect given the 5.0 V8 and 400 PS.

But it's not just the donk, heh. The Subaru et al have the aerodynamics of a house brick to stick 'em on the tarmac, this creates lots of drag, and it'll make quite a difference. That and low compression engines, too, plus gearing that's optimised for performance not economy.

I appreciate that it's twenty five years ago, but a 1.6 Cortina returned around 30 mpg. Now a 1.8 Mondeo (the nearest by class) returns 35 mpg and a

1.6 Focus high 30s...

They've generally got a lot of valve overlap, so at low revs a fair bit of the petrol goes in the inlet valve and straight out the exhaust valve.

vRS 1.8T i'm getting 27mpg. Running it in the mpg was well over 30, well actually 31-32. Been testing out the traction control quite frequently of late with the greasy roads round here. I use 4th-5th gear as often as possible in moving traffic but like to drop it down a gear when the roads open up. That 27 mpg is with semi-sensible driving. At 150 (on the clock) the old primera GT used to do 7mpg.

My 1.8T on the motorway will sit at 40mpg all day long, and it's quattro, I get 480 miles to a tank @ 60litres

I think that equals 40mpg?

That flat four won't help either - a lot of valvetrain...

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