122s mpg

[Othen]

Originally Posted by packers1712

Excellent, sounds like mine must be ball park on the tune front then, also my car was supplied with a dyno sheet showing 142BHP (from back in 2016 so may not quite be that still, trying to get it back on the rollers for confirmation)!

Doug.

Did you ever get Mr Roberts checked on the dyno again Doug? 142HP would be very impressive indeed .

Alan

[packers1712]

Hi Alan,

Yes I did having been around the houses with it a bit (twin 40 DCOE installed- dyno'd, didn't like how it ran- removed DCOE's and re-fitted SU HS6's & re-dyno'd found to be running too rich at fast idle-needles in SU's replaced for larger ones & re-dyno'd again) got there in the end but numbers weren't as impressive as the supplied dyno sheet with the car had suggested, Mr Roberts has 97bhp at the wheels and Neil, the dyno operator suggested flywheel hp of approx 130 given the tyre size I have fitted and total transmission loss!
The debate about how to calculate bhp to flywheel hp will no doubt re-ignite and can be argued indefinitely at the same time as altitude, ambient temperatures etc, etc!

Now obviously the factors that allow the above results to be arrived at are considerable and its probably fair to assume the rolling road that produced the dyno sheet supplied with the car was ambitious, ultimately he is running the best he ever has so the numbers are somewhat inconsequential, I'm more than happy with the performance given his age and that's all that really matters!

I've yet to do a "proper" MPG check but I've accepted it is what it is, the grin factor while driving him out weighs fuel consumption concerns!

Doug.

[Othen]

Originally Posted by packers1712

Hi Alan,

Yes I did having been around the houses with it a bit (twin 40 DCOE installed- dyno'd, didn't like how it ran- removed DCOE's and re-fitted SU HS6's & re-dyno'd found to be running too rich at fast idle-needles in SU's replaced for larger ones & re-dyno'd again) got there in the end but numbers weren't as impressive as the supplied dyno sheet with the car had suggested, Mr Roberts has 97bhp at the wheels and Neil, the dyno operator suggested flywheel hp of approx 130 given the tyre size I have fitted and total transmission loss!
The debate about how to calculate bhp to flywheel hp will no doubt re-ignite and can be argued indefinitely at the same time as altitude, ambient temperatures etc, etc!

Now obviously the factors that allow the above results to be arrived at are considerable and its probably fair to assume the rolling road that produced the dyno sheet supplied with the car was ambitious, ultimately he is running the best he ever has so the numbers are somewhat inconsequential, I'm more than happy with the performance given his age and that's all that really matters!

I've yet to do a "proper" MPG check but I've accepted it is what it is, the grin factor while driving him out weighs fuel consumption concerns!

Doug.

Thanks Doug,

That is really interesting.

I could not agree more about the satisfaction of running a well sorted out motor car completely overshadowing whatever maximum power output the engine might have. GAM has a B18D motor (so twin SU carburettors and low compression) rated at 90HP - I rather suspect that was at the flywheel rather than roadwheels. In practice that works very well indeed, just enough to keep up with traffic and plenty for the skinny tyres, chassis and brakes.

I keep records of GAM's fuel consumption every time I fill up (only about once every 6 weeks). For running around town (90% of its use) it does 21-23MPG. I'm planning to take it to the Amazon get-together at Southwold on 21 May and will measure the consumption then. I think I may get close to 30MPG now that the overdrive is sorted.

[Clan]

Originally Posted by Moomoo

My ‘66 ,121 would do high twenties in the situation you describe. The tune is critical, I found ,like with most old motors, plugs,points, carb,air filter.

Mine, had no overdrive.👍

Indeed, It is so easy to get the carburettors set wrong which will increase the fuel consumption dramatically with no driving symptoms. It is essential to get someone with a co meter to set them up then never twiddle with them as they don't wear or alter on their own.
( All assuming compressions are equal and correct and the car is serviced properly, with decent quality points. )

[Othen]

Originally Posted by Clan

Indeed, It is so easy to get the carburettors set wrong which will increase the fuel consumption dramatically with no driving symptoms. It is essential to get someone with a co meter to set them up then never twiddle with them as they don't wear or alter on their own.
( All assuming compressions are equal and correct and the car is serviced properly, with decent quality points. )

I have a CO meter, but I can't find a specification for the CO content in the green book.

I'd be very surprised if an Amazon (or any similar 1960s motor car) would achieve high-20s fuel consumption running around town. Back in the day 30MPG on a run was considered very good for a small car on a run (I think I recall Ford advertising the Escort of the day achieving 30MPG, but that was probably with an 1100cc engine). I don't think there is anything wrong with the way GAM's motor is set up.

[Clan]

Originally Posted by Othen

I have a CO meter, but I can't find a specification for the CO content in the green book.

I'd be very surprised if an Amazon (or any similar 1960s motor car) would achieve high-20s fuel consumption running around town. Back in the day 30MPG on a run was considered very good for a small car on a run (I think I recall Ford advertising the Escort of the day achieving 30MPG, but that was probably with an 1100cc engine). I don't think there is anything wrong with the way GAM's motor is set up.

genearaly about 2% the MOT will ensure it is never more than 3.5% anyway so it can't be too far out I guess.

[Othen]

Originally Posted by Clan

genearaly about 2% the MOT will ensure it is never more than 3.5% anyway so it can't be too far out I guess.

That would have been my guess (GAM isn't liable for MoTs any more); although 2-3% is a sensible guideline it doesn't particularly help much in setting up the two SU carburettors (except as a gross error check).

The green book doesn't have a specification (I suppose no one had thought of analysing the exhaust gasses of a motor car back in 1963). I'm pretty sure I have the SU carburettors right, so I'll probably carry on tuning them by ear as I've always done .

[Juular]

I often wonder how these would fare with a later redblock installed, for example a B230E. Given I can squeeze 35mpg out of the much heavier 240 on a run, in the 122 with overdrive it might be a real practical daily car.

[packers1712]

Is the B230E FI or carburettor'd?

Doug.

[Othen]

Originally Posted by Juular

I often wonder how these would fare with a later redblock installed, for example a B230E. Given I can squeeze 35mpg out of the much heavier 240 on a run, in the 122 with overdrive it might be a real practical daily car.

Originally Posted by packers1712

Is the B230E FI or carburettor'd?

Doug.

I think that would work pretty well, as long as you could get the gearing high enough to take advantage of the extra power. I think the highest ratio rear axle in a standard Amazon is 4.1:1, so you might have to fit a rear axle from a 240 (or 740) with a 3.31:1, 3.54:1 or 3.73:1 ratio, 131HP would have no problem pulling overdrive and would probably achieve 35MPG. I recall reading about someone that did that somewhere in these pages - the other big advantage would be disc brakes at the back !

I'd say that would be the way to go for a skilled chap like yourself Juular. Your B18 motor is pretty worn anyway, so a fuel injected, 2.3litre 4+1 speeder with rear disc brakes and a 3,54:1 rear axle would be a good solution, within your capabilities and quite something when finished.

Doug: B230e is K-Jetronic FI - mechanical so pretty easy to graft on.