Fast, Fun, Frugal

[Guran]

The May 2009 issue of WHEELS magazine has a feature article called "Fast, Fun, Frugal" in which they track & road test a group of performance cars that have an ADR81 fuel consumption figure of less than 10L/100km. It's an interesting academic exercise. The 135i Coupe qualified for the mix ... just (9.6L/100km ADR81). It was ranked 6th, despite being the 3rd fastest around Oran Park's south circuit (51.85s, behind 911 Carrera PDK on 49.89s and Lotus Elise SC on 50.79s), 2nd quickest to 100km/hr (5.4s behind 911 on 4.9s), and the 4th most fun (behind Elise SC, then 911 and Clio 197). The let down for the 135i was fuel consumption which was the highest of the lot at 16.5L/100km. The fun score was also reduced by the lack of an LSD which meant it was "hard work, but fun" on the track at 10/10ths. The winner? Renaultsport Clio 197.

[spdrcr]

Lets be honest, the 9.6L/100km is a joke. I think it would be difficult to get this on a freeway.

[Guran]

Actually, looking at the data more closely, it appears that it was mainly the "affordability" score (ie. list price) that influenced the placement of the 135i. Take list price out of the equation, and the 135i finished 3rd behind the Lotus Elise SC (1st) and Porsche 911 Carrera PDK (2nd), and only just ahead of the Clio 197 (4th).

[Guran]

Originally Posted by spdrcr

Lets be honest, the 9.6L/100km is a joke. I think it would be difficult to get this on a freeway.

Let's face it, the ADR81 figure is only ever intended as a relative comparison with other cars under controlled conditions. It involves half an hour on a wheel dyno, monitoring of exhaust emissions, and a complicated calculation. You should never expect that this is the sort of fuel consumption you'll achieve on average.

On the other hand, the lowest fuel consumption I have recorded with my 135i is 9.70L/100km. That was probably with mostly freeway driving, but nothing special like hyper-miling techniques or anything silly. I've also had 9.76 and 9.80L/100km. At the other end of the spectrum, my highest is 12.7L/100km.

The fuel figures WHEELS recorded where after a 115km road loop of urban crawl and freeway cruising, followed by a few laps around the south circuit at Oran Park and straight line drags on the main straight. So they were always going to be much higher than the ADR figure. But the record goes to the Audi A3 which has an ADR81 figure of 5.8L/100km but drank 98RON at the rate of 15.6L/100km in the tests!!! In comparison the 911 drank 15.6L/100km compared with the ADR figure of 9.6L/100km (same as the 135i). Most of the cars used 50-70% more fuel than the ADR figure which is no surprise considering they spent a lot of time at WOT.

[lavaletta]

The track times I can understand, but the straight line acceleration (5.4 secs) seems a bit slow. Did it say whether it was a step or manual?

[qship]

I must be doing something wrong. I havent reset the fuel consumption meter for about 3000k! Imust visit a race track one day................

[Alext]

8.9l/100km after 3000km?? You must do a lot of highway mileage!!

[Guran]

Originally Posted by lavaletta

The track times I can understand, but the straight line acceleration (5.4 secs) seems a bit slow. Did it say whether it was a step or manual?

It was a manual. WHEELS always test with driver and passenger in the car, which means that their times are typically a bit slower than everyone else. They've been doing it this way for 56 years and not likely to change it! This is actually the third time they've tested 0-100km/hr for the 135i: Oct 2008 was 5.5s and Nov 2008 was 5.6s. So this is their best result and is only 0.1s slower than the BMW claim of 5.3s. Ditch the passenger and it would be possible to better the BMW claim.

[qship]

Admittedly more than most. About a 50:50 mix of city and country driving. The Porsche and elise times should be tripled as this is how long it would take them to take 3 passengrs around a race track!

[TP 135i]

Originally Posted by spdrcr

Lets be honest, the 9.6L/100km is a joke. I think it would be difficult to get this on a freeway.

Interesting statement.............
Over 12,000 miles I've averaged 10.00L/100km (23.5 mpg, US)
With all highway driving I've gotten 7.42L/100km (31.7 mpg, US) The highway drive was with little or no traffic and with very easy acceleration and top speed of around 105 kph (65 mph).
9.6L/100km seems very easy to achieve.

[sparoz]

Swapping the RFT out apparently get you an extra 10-20%. That's what the tire guy reckons from less unsprung weight - imagine what will happen if I lighten up my wheels as well

[amk2912]

I did a run last weekend down to Margaret River in the SW of WA. I filled up down there and when I got back I had 467km on the odo and it took 43.8 litres to fill the tank - this means a range of 560km on a full tank and 9.3L/100km.

I'll report back this weekend after a BMW track day this Friday...be interesting to see how the consumption goes after a day of hard driving!!

[Blacky]

Originally Posted by qship

I must be doing something wrong. I havent reset the fuel consumption meter for about 3000k! Imust visit a race track one day................

That is sensation, the same as I get from my 130 so the twin snails don't harm the fuel consumption if you drive it right

[jksgoh]

Originally Posted by Blacky

That is sensation, the same as I get from my 130 so the twin snails don't harm the fuel consumption if you drive it right

my 125i uses more than that! and with a significant amount of it being freeway driving as well!
think my average is sitting at about 10.2 now...

[oldman]

I recently did a trip from Central Coast to Bowral and back (yes.. mostly highway) with a JB+ installed and averaged 8.7 which I thought was really good.

[TimMc]

Originally Posted by sparoz

Swapping the RFT out apparently get you an extra 10-20%. That's what the tire guy reckons from less unsprung weight - imagine what will happen if I lighten up my wheels as well

Sounds like BS sparoz. Lighter unsprung weight will help with suspension response, have a slight affect on fuel consumption around town and bugger all at constant speed on the highway. Might help outright acceleration a little.

[Blacky]

Originally Posted by jksgoh

my 125i uses more than that! and with a significant amount of it being freeway driving as well!
think my average is sitting at about 10.2 now...

just looked and my current fuel economy is 8.8

I do a lot of freeway driving in Melbourne, but I also drive the suburbs but don't drive to work in peak hour.

[RadiuM]

damn local newsagent doesn't have the may edition yet.. so I bought the Wheels 2009 best buys.

the 1 coupe got the best Coupe under 100k!

[Guran]

Sorry forgot to mention that I get my WHEELS via subscription. I think it goes on sale in newsagents from Thursday this week.

[oldman]

Just went to the newsagent and he said it comes out tomorrow.

[barrym]

umm.. are you sure two up? check the pictures ..i don't see passangers in most shots ..perhaps for laps its just driver and two up for sprint times?

[barrym]

also - I dont like the sound of this whole "overpowered chassis" business .. he's almost saying the chassis is overwhelmed by the power ..and that the oversteer / understeer situation returns to normal state when off track and on the road ..I'm worried as I want to potentially track one of these one day ..perhaps tht's where the Performance components will make the difference in terms of suspension, sway/tortion bars etc etc ...overall though they wernt very kind in terms of dynamic ability of stock 135i