Er, Economy?

Author
Discussion

mduroe

Original Poster:

40 posts

261 months

Thursday 8th April 2004
quotequote all
Chaps,

Just a recent purchaser of a 3R, and I wanted to check something with you all. Aside from the tank on the 3R seeming incredibly small (is this something to do with the fact that the sender is not at the bottom of the tank so registers it empty when it still has quite a bit of fuel in?)

Anyway, I'm still running mine in. It seems to cost only about £30 to fill the car up, and if I'm lucky, not doing hard driving (I can't, yet), I get 90 miles town driving. Ferraris are more economical. Can this be right? Not bothered so much about the economy, just wondered if this was to be expected.

Also, is anyone else having teething problems with the build quality. When I picked mine up from the showroom, there were scratches on the hood where it looked like someone had opened it with a set of keys clutched in his hand, the gearnob also looked like a few shifts had been admisinstrated by a heavily bejewelled hand, and the window winder rubs against the door leather to make a nice circle (actually there was one already when I picked the car up)

Also, another niggle. If you look at the lip of the front of the bonnet, which you can from your seat, does the underneath protector-layer (looks like black paint) bleed over the lip and look like rough brush-strokes along the edge of the panel. And my wheels seem to rub against the body at full lock in both directions. Anyone else getting these?

Just curious,

Marcos

crb1

922 posts

249 months

Thursday 8th April 2004
quotequote all
Marcos,
I've had my 3R for 3 weeks and covered 1850 miles. Average mpg is 19.7. I get somewhere between 170 and 200 miles per tank which usually needs approx. 40 litres to brim. IMO mpg during running in should be a fraction higher if you are being good to your car!
As to your problems (I have none of these) make sure your dealer corrects them at the 1000 service.
Chris.

amg merc

11,954 posts

260 months

Thursday 8th April 2004
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Marcos, doesn't sound right - was yours a new car and who is your supplying dealer?

Micknall

826 posts

256 months

Thursday 8th April 2004
quotequote all
The M12 has a 64-litre tank capacity, and yes, you're right, it generally takes only 40-litres to fill when the gauge is on empty. So there's a generous safety-margin, but this is by design.

We recommend owners not to run their cars below a quarter of a tank, especially if they're driving fast on a twisty road or circuit, due to the risk of fuel starvation. However, on a straight motorway running to 'E' on the gauge is okay.

If you sit at between 90-100mph on, say a motorway, you should get about 23mpg, or around 200 miles to 40 litres. This figure rises to 28mpg if you sit at a pretty constant 70mph.

When we've figured the car, mpg has dropped to 8mpg, but that's not unusual for a biggish-capacity performance car. Overall, driven briskly on a variety of roads, you should get between 20 and 22mpg.

gizard

2,254 posts

290 months

Thursday 8th April 2004
quotequote all
The Fuel tank is aprox. 60 litres - but the sender will say that it's empty when there is aprox. 15 - 20 litres left - this is to prevent fuel starvation on track days during hard cornering (which can destroy the engine) - so with normal driving you should be able to drive a bit further. Going on the average of 20 mpg (normal driving) you should be able to get around 50-60 miles with some spare.

Guy

RobP

2,097 posts

248 months

Thursday 8th April 2004
quotequote all
Marcos- as everyone has pointed out the fuel guage is wildly inacurate; a 'safety' feature to prevent inadvertant fuel starvation apparently. Personally, I would prefer accuracy.
I've just completed my first 1000 miles and,assuming the mileometer is accurate(!)averaged about 23mpg using the full tank method. Best (economy-wise) was 25mpg. This was keeping revs below 3000 rather than the 4000 factory recommendation.
No problems at all with build quality , other than a missing screen-washer mechanism on the passenger side; which was a fuss free correction at the 1000 mile service. Also had the seat runners moved forward as I am a short-arsed bleeder - I can now fully depress the clutch without pivoting my hip, but am sitting too much ahead of gear lever and hand-brake. Maybe a bespoke lumber support might be in order , but if anyone has any (sensible) suggestions, I'll be glad to hear..

brianj

256 posts

249 months

Thursday 8th April 2004
quotequote all
Factory has lumbar support and headrest available as extras trimmed to match, I believe, as I need to order for my (small) wife.

Brian

RobP

2,097 posts

248 months

Thursday 8th April 2004
quotequote all
Thanks Brian -I tried one at Mole Valley, but it was more a 'whole back' support than a lumber support. Did the trick in terms of pushing you further forward, but left you in a sit-up-and-beg driving position, with very little lateral support and no shoulder support from the seat. What I need is something that only pushes hips forward...

amg merc

11,954 posts

260 months

Thursday 8th April 2004
quotequote all
RobP said:
, but if anyone has any (sensible) suggestions, I'll be glad to hear..


Rob, don't know if they'd do this but maybe ask the factory whether they'd rig you up an adjustable pedal box (I believe that TVR offer the option). You can then have the pedals set closer to you, thus sit further back on the seat runner for an improved gear-change?!

V6GTO

11,579 posts

249 months

Thursday 8th April 2004
quotequote all
Would it not be possible to have the pedals cut and welded so the part you push with your foot is a couple of inches further forward? Or baybe some 2" blocks on the pedals? (Yes, I am being seroious!) M.

DanH

12,287 posts

267 months

Thursday 8th April 2004
quotequote all

Maybe you could fit and aftermarket metal pedal on top of the current one you have. They are normally used by maxxers to give that authentic drilled pedal race car look (*ahem*) so they are designed to mount on top of what you already have. Would probably help a bit?

Otherwise perhaps the factory can adjust the pedal. Did you find this problem during the test drive?

ashleyw@sicl.co.

3,836 posts

248 months

Thursday 8th April 2004
quotequote all
Curious, why would fuel starvation kill an engine?

m12_nathan

5,138 posts

266 months

Friday 9th April 2004
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Fuel is used to cool the pistons, no fuel = melted pistons. This is the case on all engines, not just the noble.

ps. we are talking about 6500rpm round a corner, the fuel is moved off the pick up by g force, not simply running out of petrol.

matt_t16

3,402 posts

256 months

Friday 9th April 2004
quotequote all
ashleyw@sicl.co. said:
Curious, why would fuel starvation kill an engine?



Turbo'd engine with high combustion chamber temps and pressures. Fuel starvation would equal a lean condition as fuel pressure in the rails dropped away (less fuel pressure, less ooomph behind the injector when it opens so less fuel metered for a given pulse length). Lean condition leads extremely rapidly to a very large increase in heat, both the burn temp of the mixture and the resulting temp of the combustion chamber (think what happens when you blow on a burning ember) and usualy to detonation/knock. Combination of these two will kill an engine dead, usualy by melting a couple of pistons.

Note: Any force inducted engine and most very high compression N/A engines will suffer in the same way.

Cheers
Matt

>> Edited by matt_t16 on Friday 9th April 00:23

ashleyw@sicl.co.

3,836 posts

248 months

Friday 9th April 2004
quotequote all
Thanks guys.