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[Entwood]

AHHHH .. methinks I spot something ....

Are you resetting the average mpg every trip If so it is highly inaccurate over short distances, a traffic queue will drop it amazingly fast on anything less than a couple of hundred miles.

[geoffr70]

AHHHH .. methinks I spot something ....

Are you resetting the average mpg every trip If so it is highly inaccurate over short distances, a traffic queue will drop it amazingly fast on anything less than a couple of hundred miles.

Ergh :-/ yes! Most of the time, well all the time actually! I know it's not recommended, but I still do it. Perhaps with the trip not being accurate, it's counter productive as you say?

[tunnie]

only 28mpg? nothing to shout about. I get 27mpg average from a 3.0 Auto Estate and not sparing the horses!

I had a pre-facelift 3.0 estate auto for a few months, i easily, easily, got 30mpg with a light right foot.

With a manual, i'd expect mid 30's. As said, your labouring the engine, 4th gear at 20mph is going to labour it, and badly too. Use the gearbox properly, and with clean breathers, mid 30's is easily achievable.

I don't think I am labouring the engine. Anyway how did you get that from an auto? I used to get about 20 mpg. Half way through my current tank I'm on 17.8, that cannot be right. I've got no vac leaks, fully serviced, clean oil, clean breathers etc etc. Most of my journeys are short, but still?

As others have said, 4th gear, 20mph you are laboring the engine, sorry but thats a fact.

Clean breathers and good servicing, 30mpg average is easily achievable,  from a 3.0 auto. A certain admin as got i think 24mpg average over past 3,000 miles, and he drives with the throttle off or on 

[humbucker]

on average i was getting 35mpg out of my elite. admittedly all motorway miles and it's pretty flat round here, but 28mpg doesnt sound all that great to me?  :-/

[Kevin Wood]

IMHO the most efficient RPM range is between 2000 and 3000, don't floor it to get there and don't drive up to something then smack the brakes. Anticipation and smoothness are what you are after.

Nail on head. It's a fallacy to believe that running the engine in the lowest gear you can is good for economy. Just because it will pull from low revs doesn't mean it's best for economy.

Engines are, in general, most efficient at the bottom end of the rev range where they have decent torque delivery, so about 2,000 RPM and above for the V6.

Below that, the engine isn't moving the intake or exhaust charges quickly enough for the cams to work properly. If the engine had carbs it wouldn't be driveable in that rev range. Fuel injection resolves that but it's inefficient nevertheless.

Kevin

[robbo2345]

agreed geoff when i had my vecci 2.5 irmshcer would do the same no problem on level ground 

Right on robbo! I bet your veccy still pulled like a beast!

Sure did geoff terrific piece of kit chipped too it was ex-plod quick response (Norwich to Yarmouth in 15 mins ) with regards to mpg my old 3.0 elite saloon returned 39.8 on a run 

[geoffr70]

only 28mpg? nothing to shout about. I get 27mpg average from a 3.0 Auto Estate and not sparing the horses!

I had a pre-facelift 3.0 estate auto for a few months, i easily, easily, got 30mpg with a light right foot.

With a manual, i'd expect mid 30's. As said, your labouring the engine, 4th gear at 20mph is going to labour it, and badly too. Use the gearbox properly, and with clean breathers, mid 30's is easily achievable.

I don't think I am labouring the engine. Anyway how did you get that from an auto? I used to get about 20 mpg. Half way through my current tank I'm on 17.8, that cannot be right. I've got no vac leaks, fully serviced, clean oil, clean breathers etc etc. Most of my journeys are short, but still?

As others have said, 4th gear, 20mph you are laboring the engine, sorry but thats a fact.

Clean breathers and good servicing, 30mpg average is easily achievable,  from a 3.0 auto. A certain admin as got i think 24mpg average over past 3,000 miles, and he drives with the throttle off or on 

i don't think so

[geoffr70]

agreed geoff when i had my vecci 2.5 irmshcer would do the same no problem on level ground 

Right on robbo! I bet your veccy still pulled like a beast!

Sure did geoff terrific piece of kit chipped too it was ex-plod quick response (Norwich to Yarmouth in 15 mins ) with regards to mpg my old 3.0 elite saloon returned 39.8 on a run 

I get about 9-10 mpg from a 1982 Dennis RS133, fitted with the 540 engine. (10.5 litre N/A V8 diesel!) With an Alison MT643 autobox (IIRC). It's only putting out 149 kw, don't know the torque firgures, but it shifts and is easily as fast as modern Dennis fire engines and faster than the Volvo FL614s by a long shot! I've had 77 out of it and it weighs 12 tonnes with all the kit!

[robbo2345]

agreed geoff when i had my vecci 2.5 irmshcer would do the same no problem on level ground 

Right on robbo! I bet your veccy still pulled like a beast!

Sure did geoff terrific piece of kit chipped too it was ex-plod quick response (Norwich to Yarmouth in 15 mins ) with regards to mpg my old 3.0 elite saloon returned 39.8 on a run 

I get about 9-10 mpg from a 1982 Dennis RS133, fitted with the 540 engine. (10.5 litre N/A V8 diesel!) With an Alison MT643 autobox (IIRC). It's only putting out 149 kw, don't know the torque firgures, but it shifts and is easily as fast as modern Dennis fire engines and faster than the Volvo FL614s by a long shot! I've had 77 out of it and it weighs 12 tonnes with all the kit!