NBW

I've read in several threads that as standard, the Turbo 'over fuels' to prevent the engine running lean. Hence 20-25mpg.

Question, what would you need to fuel accurately, and have a safeguard that prevented the engine running lean?

Second, how much would this cost?

Third, having done this what mpg is achievable on a motorway run at a steady 80/85mph?

Cheers
Tim
MY '00 (not a gutless one ), engine standard but WR Sport BB and soon to be fully de-catted.

Luke

good post. would like an answer to!!!

Deane

Hi there

The way I have managed to get reasonable economy is fitting the Apexi Super AFC. This was initialy to ensure that I was getting enough fuel when on high boost. But is has two throttle settings so you can lean off the fuel mix when not under load. This must be done with extreame caution as we all know what can happen. I had mine set up by DP Motorsport in Warrington. I have managed to get about 250 miles out of one tank on a motorway cruse at a reasonable speed. I think that my Lamba is now playing up and I am now only getting 210 to a tank, still not too bad.

Hope this is of some use.

NBW

Deane,

I already do 300 miles on a tank if it includes a lot of motorway driving. Usually get 27 mpg on a run, occasionally 29.

Otherwise it's <= 25 mpg.

Cheers
Tim

john banks

If you use an interceptor type computer to modify say the MAF signal before the ECU in closed loop zones would the ECU just adjust it back again using the (correctly functioning) lambda sensor?

Anyway, why would you want to run leaner than stoich?

Is the issue with a Scooby that boost is very addictive and the car is thirsty on boost?

My wife can get 32mpg in our Scooby oh her work commute. She averages 28mpg in her Pug 3.0 V6. I get about 21mpg in the Scooby and 23mpg in the Pug. Now our cars are not as economical as equivalent powered Saabs or Volvo turbos of say 200-250bhp even though they are heavier, but most of it is still the driver. You have the toys, you pay for them is my thinking. Otherwise a PD TDi or a 320 or 330d is on the cards.

NBW

John,

See your point entirely. I can live with the fuel consumption generally, but occasionally I do longer motorway trips, usually on business, and the cost of fuel is not entirely covered by what the company reimburses me.

I was just wondering if there was something I could do that would be cost effective.

I take your point about breathing mods and leaning out, and may be the decat (can't wait!) will improve mpg. However, my experience tells me that once there is more performance you tend to use it thereby negating any effiency gained (from an economy perspective).

PD TDi or 320/330D ? I don't think so, not just yet

What set me thinking was a colleague has just got a TT 225, and now that it's run in he regularly gets low 30's on a motorway run. I guess it's slightly more aerodynamic than our cars, but it's also 100KG heavier.

Thanks
Tim

SecretAgentMan

The only way to get a better mpg is to remap, it runs silly rich with the stock ECU.

I am seeing much better mpg with the link now - if I want to...
If I have fun it gets much worse. *lol*

/J

Goldfinger

I've got a MY99 Turbo 4dr with SS BB and ITG panel filter (definitely not a gutless one ). Does a mixture of driving (ie: a bit of 'spirited' driving, motorway, urban etc.) I get c. 24 mpg but during my annual blast down to Croatia to see the in-laws on SUL 98 RON I got more than 400 miles on a single tank without the red light coming on cruising at a constant 90mph or so in warm weather ... this equates to low 30s which is bloody good. I find the fuel consumption has dropped markedly during the winter - anybody else noticed a difference.

I have had mpg down in the low teens once or twice as well

Cheers
Phil

john banks

Breathing mods can lean you out a bit.

At cruise the car fuels quite sensibly using the lambda sensor. On boost or at high revs it is open loop and chucks fuel in as per the MAF sensor mainly. With some cars running 10% CO or more this is rich, but the advantage is it gives cylinder cooling and knock control and the engines last well.

A remap may give you better economy. Some map for 7% CO on boost which gives more power, but on a small turbo at high boost may run hotter than at 10%.

I am not a mapper this is just my basic understanding.

[Edited by john banks - 2/8/2002 10:22:51 PM]