Car (or bike) Chat!

[Audio Advent]

Ha! I did a 200 mile trip on just £25 the other day. And I was being a bit of a prat driving wise on the motorway (gave myself a talking to afterwards - it's a relatively new car to me and it's quite fast) ! But that's because it was LPG at 53p a litre.. and my quick calculation gives about 20mpg for that trip. A bit disappointed with my fuel economy on my Saab Aero - only getting like 23 mpg average in town, 30mpg if I reset it and drive calmly on a motorway.

£40 and 270miles in a 3.5l engined car is pretty good - I work that out as 36.5 mpg assuming £1.20/l for the fuel. 50mpg would be £30 (that's your new target).

[walpurgis]

I used LPG (dual fuel) company cars for a few years and the performance drop off when switching to LPG was very noticeable. Needless to say, the LPG option was only used as a back-up.

[StanleyB]

A bit disappointed with my fuel economy on my Saab Aero - only getting like 23 mpg average in town, 30mpg if I reset it and drive calmly on a motorway.

Lucky you. I get 18MPG on average in my SAAB. Motorway is around 27MPG.

[Marco]

I keep getting a niggling feeling that I should look for one of these as a replacement for my second car: http://www.autotrader.co.uk/classifi...colt&logcode=p

They are rare and well below the radar. Seriously nippy. Supposed to be a hoot to drive.

Treat yourself, Geoff. Life's too short, mate, to deprive yourself of some well-deserved fun!

Marco.

[Marco]

A bit disappointed with my fuel economy on my Saab Aero - only getting like 23 mpg average in town, 30mpg if I reset it and drive calmly on a motorway.

£40 and 270miles in a 3.5l engined car is pretty good - I work that out as 36.5 mpg assuming £1.20/l for the fuel. 50mpg would be £30 (that's your new target).

Saabs seem to be rather thirsty... You and Stan should be able to achieve better fuel consumption than that. Are both your cars petrol engines?

I'd probably get nearer to the 50mpg mark if I drove slower next time, but that wouldn't be as much fun - and there's not much point in having a car like that if now and then you don't enjoy what it can do [haring round tight bends at 65mph, and the like]! My Brabby's very spoiled, though.

I keep her in tip-top condition (as car tweaking/engine tuning is a big hobby of mine now, even more so now than hi-fi), with the engine kept tuned to the peak of its performance. It's been 'Terracleaned', so all internal built-up carbon deposits have been removed, which improves both performance and economy, always 'fed' with the best fuel, either Shell V-Power Nitro+ or BP Ultimate diesel), and oil. The latter currently Ester-based Silkolene/Fuchs Race Pro S 5W30.

I also occasionally use Valvoline Syn-Power Diesel fuel system cleaner, which is excellent:




The car has also been fitted with K&N air filters and a WIX Racing oil filter. I check the tyre pressures every week [nitrogen filled], ensuring that all are at the optimal PSI level (which makes a big difference when it comes to fuel economy), and low-profile Pirelli P Zero Corsa tyres have been fitted. Good tyres also improve fuel economy. The car also has a sports body-kit and lowered sports suspension, all of which makes it pretty aerodynamic.

Therefore, I think the fuel consumption figures I'm getting are probably testament to a combination of all of the above

Marco.

[Audio Advent]

Saabs seem to be rather thirsty... You and Stan should be able to achieve better fuel consumption than that. Are both your cars petrol engines?

Yeah.. don't know what that's all about. I thought Saabs would be efficient. Then again it's the Aero (sporty) version. 2.3 turbo. All saabs are turbos so perhaps they just push too much fuel into each stroke? Petrol, yes.

The car has also been fitted with K&N air filters and a WIX Racing oil filter. I check the tyre pressures every week [nitrogen filled], ensuring that all are at the optimal PSI level (which makes a big difference when it comes to fuel economy), and low-profile Pirelli P Zero tyres have been fitted. Good tyres also improve fuel economy. The car also has a sports body-kit and lowered sports suspension, all of which makes it pretty aerodynamic.

Therefore, I think the fuel consumption figures I'm getting are probably testament to a combination of all of the above

Marco.

Nitrogen filled tyres?! What? What does that do (other than mean you can't pump them up with a foot pump)? Doesn't help I guess that the Saab has done 172k, is 15 years old and owner before last was a rudeboy. Rear suspension is saggy (common fault over time, the bushes go) which causes wear on the inside of the tyres and mine have been swapped to the front so need to get those and the suspension sorted which may help.

Stan: I read on a Saab forum that if you take a particular fuse out of the Saab for 15 minutes, the ECU then resets and learns your driving style and then sets up for that. So, if you want it to be more performance oriented, you take out the fuse, replace it and then go burning up the streets for a bit! If you want it to more economical you do the first drive all smooth and slow acceleration etc. Now, I don't know what models that applies to to be honest but I'm hoping (if it's true in the first place) it applies to my year 2000 model.

[Audio Advent]

I used LPG (dual fuel) company cars for a few years and the performance drop off when switching to LPG was very noticeable. Needless to say, the LPG option was only used as a back-up.

I've found no real difference, except for two things: when the LPG is in use the ECU isn't adjusted properly for it so it doesn't idle at the right revs and you have to give a smidgen more pedal to stop it stalling on pulling off. second, when you begin to run out there doesn't seem to be enough pressure in the tank to get all the fuel you need when putting your foot down so you can get a bit of hesitation if not complete fuel starvation and refusal to act (then I just switch over until I'm driving steady again). I guess that's down to the practicalities of an after market LPG tank in the boot rather than it being part of the design of the whole car.

LPG is higher octane than normal petrol so an engine designed for LPG should be able to get more performance out than normal petrol. My Saab being a turbo means it might be utilising that higher octane in that it can achieve higher compression without any pre-ignition and so wiz up the turbo faster than with petrol without causing problems.. but I don't know if the ECU actually controls the turbo compression in any way at all. I'm sure it could though if tweeked!

I think LPG is great: much lower emissions, half the price, same fuel economy and I don't notice any performance difference (other than the particular tuning issues on my car).

I might try the fuse-out reset trick and start up with LPG to see if it will re-map itself to the LPG instead of petrol as I try to only use LPG for financial reasons. I've not had the car that long as you might guess..

[Marco]

Nitrogen filled tyres?! What? What does that do (other than mean you can't pump them up with a foot pump)?

See here: https://shop.atseuromaster.co.uk/car...en-inflation/8

It's what's used in Formula One racing cars, and as stated, keeps the correct tyre pressure for longer. I've tested this now over a period of two years, and it definitely works. With normal air, I used to lose around 2-3psi a month on some tyres, and now with nitrogen, nothing.

With sports suspension and very low-profile tyres (30, on 19" rims), you can really feel the difference in how the car handles when the tyre pressures are right, and when they're not. And with nitrogen inflation at only £1.25 a tyre, which lasts ages, it doesn't break the bank either....

I check the tyre pressures weekly, with my own gauge, and as soon as any of the tyres lose pressure, I pop along to my local ATS (5 mins from my house) and the lads there perform the nitrogen inflation. It takes minutes, and I get a nice coffee there, too!

The other thing I'm anal about is ensuring that the wheel balancing and tracking are *spot on*, so I have the latter regularly checked too, especially with the condition of the roads these days! All that makes a big difference to how your car handles (which impacts on the driving experience), and how long your tyres last. And at around £230 a pop, for the Pirelli P-Zero Corsas I use, I want them to last for as long as possible!

Outside the car dealership, where I bought da Brabster:





And outside of my humble dwelling:







Marco.

[walpurgis]

The Nitrogen thing is strange, considering that roughly 3/4 of normal air IS actually Nitrogen. I don't see how using pure Nitrogen in tyres can make a difference.

[Marco]

Trust me, mate, it does. The figures don't lie. Over a period of two years now of using nitrogen, when testing my tyre pressures, they are staying constantly correct for much longer.

Marco.