Mpg !!!!

[Sohail]

Evening all

Me again !!!!

Just calculated mpg for yesterday's trip which was a mix of motorway, a and B roads. Am only getting 18 mpg, my car is a auto. That sounds low to me. Any ideas on What coud be causing it please.

Thank you

Sohail

[richardthestag]

Heavy right foot?

when my stag was auto with tv8 and strommies 18mpg average was about right for it. On one particularly enthusiastic drive home from france i was a lot worse than that best i ever got on the bw35 was 22mpg and that was driving pretty carefully, well for me anyway.

now that the car is Manual o/d i can almost touch 30mpg on a motorway run, cruising at the legal speed limit but being gentle with the throttle. With a heavier boot it will still do low 20's on a decent run but the smile on my face is bigger

round town i dread to think, its only money.

the car seems more economical when it is supping on decent super unleaded than supermarket 95ron.

[martin]

Depends on a large number of variables, too many to diagnose on here. Just to counter Richard's experience, crossing France to Switzerland, with my BW35, 31 mpg, still repeatable. If I press hard, it drops to about 18, but usually in stop start, does about 22. No complaints.

[cliff wilkins]

Did 220 miles on the drive it day and my mk2 auto did about 19 20 mpg i worked out taking it fairly easy
50 to 60 mph max all day

Cliff.

[ChasR]

In my Stag doing 70-80MPH down the motorway it does around mid 20s MPG. As an example I went to Brean Sands with a few friends a fortnight ago. Going down there at 50 (the lock up drive going in and out was 'fun'), and then doing 80MPH on the way back had me use around £55 worth of fuel on a 200+ mile trip. When it was on Strombergs the MPG was not any better (maybe better around town, but I blame that on my right foot (it went to around 18MPG in town!).

FWIW mine is on a Holley 4 Barrel. I reckon that figure could be further improved if I took a look at my ignition system (I am fairly sure that my vacuum advance is not working).

[Guest]

Mines got a Rover lump, 3 speed auto and an Edelbrock 4 barrel downdraught (think Holley) and I get around 18mpg which, I think, is eyewatering

[KOY 23]

Fairy feet Martin is right, there are many variables. My experience of Strombergs, Holley and Weber, also BW35 and ZF:

Open road driving, BW35 around 22-24 on Strombergs, ZF pushing 30, which I would expect is similar to MOD.

Reasonably tuned Strombergs and Weber similar, Holley reduced the high 20's to very low 20's, jetting was supposedly set up for a Stag but I'm sure could have been optimised, which I did with the Weber.

Around town it's the wrong side of 20, gearbox type makes little difference.

In all situations the main variable is your right foot.

John.

[V Mad]

Check your spark plugs; what colour are they?
Check tyre pressures.
Check your ignition timing, and advance mechanisms.

[mjheathcote]

Holley and BW35 local runs 18-20, motorway around 80ish 22

[AlanD]

i have an auto, 65, i live in derbyshire so if i'm not going up a hill i'm going down one, i worked mine at around 24mpg driving steady, lower if i put my foot down, i'm happy with that, it is as the lads have said though, tyre pressures driving style etc and the set up, and the type of petrol you are using, i get better mpg from super unleaded, shell or BP i find the best

Alan

[Westfaling]

Anyone run the numbers on whether the extra cost of super unleaded pays for itself in mpg?
Nick

[richardthestag]

Just to counter Richard's experience, crossing France to Switzerland, with my BW35, 31 mpg, still repeatable.

Crikey was that on the back of one of these?

Recovery Truck.jpg

[richardthestag]

Anyone run the numbers on whether the extra cost of super unleaded pays for itself in mpg?
Nick

Not really as I only tend to use super unleaded these days in it. I dont tend to go for the really fancy expensive Shell offerings, partly because the pumps are always occupied by the Scooby crowd but mainly because normal 98ron super unleaded does it for me. When the Stag was designed and in production was it a 5star leaded petrol guzzler like the Rovers of the day? That stuff was 101ron - AvGas and racing fuel standards now.

And when I was a supermarket 95ron cheapskate the car had an BW35. Maybe this is why twinkle toes Martin can get 31mpg out of his and I struggled to get 22. what are you using Martin? apart from a feather to press the throttle that is

Some 95ron out there is awful and never never use the cheap stuff in France, makes the poor old car stutter and run so badly I though I was never going to get there. wasnt intentional but fuel warning light on, self service unmanned station, middle of france, middle of night and the only unleaded on offer was sheep urine.

[jbuckl]

18 is ok.

as others say, check tyre pressures & plug colour.

It may be possible to get slightly higher from a bw35 but not much fun if youre aiming for 31mpg

[MB]

Or get a speedo that over reads mileage. You might feel smug claiming high mpg, a bit like "pissing your pants in the rain"