WOW 29.75mpg World record!!!

[Dom B]

Well ok it's not even a club record lol, but for my car it's amazing. In the whole history of filling the car brim to brim, i have never had better than 25.5mpg in any tank. It never seemed to matter if i was cruising on motorways or mixed driving with a thrash here and there as the situation demanded. But the normal 90% of the time average was 22-24mpg

I usually drive at 75-78mph on the gps which reads over 80 on the clocks and this time the only difference i made was to drive at 70mph on a 180 mile round trip. There were a couple of days of mixed driving afterwards and when i filled up i calculated 29.75mpg which is a huge gain. I knew it was going to be better when the gauge was a fair bit higher for the same mileage but i didn't know until i did the brim to brim numbers.:rabbit:

So i guess 68-70mph is just far enough off boost, just that little lower rpm and that little less wind resistance to make it possible.

Maybe 40mpg is possible with the same power and a little low end lean burn.

Don't get me wrong i know as much as anyone that fuel+air =power and when you thrash it she will drink, but the bit that always gets me is there is no reason to drink when just cruising, that's eating up precious thrashing fuel!!

[foxdie]

Bloody hell, I thought the 261 miles I just got out of 50 litres (23.4MPG) was good :)

[Kitty's VR4]

Gee, this might be a little painful, data logging the reflashed MH7203 today, enhanced fuel/spark maps have yielded gains in fuel economy, maybe the fuel in Oz is a little better in Quality, using BP Ultimate RON98..... sit down boys....
did 445.3k using 34.2litre or 7.68L/100k or 13.02K/L (sit down now) or 36.7MPG............ my previous best was 8.36L/100k from an unflashed MH7203..... 100% highway cycle @ 100-110kph.

Just incase "Knock Values" nothing over 1, excuse me if I grin

[Dom B]

Wow that is good, i'm sure with a little remapping i can get better. But i'm pretty impressed with my figure on stock engine map.

As for fuel quality i run it on Tesco green energy super 99RON, but i believe you guys on the other side of the world use a slightly different octane rating system meaning the octane figures are a little different from ours.

36.7mpg though. WOW!! Good work.

[Davezj]

Gee, this might be a little painful, data logging the reflashed MH7203 today, enhanced fuel/spark maps have yielded gains in fuel economy, maybe the fuel in Oz is a little better in Quality, using BP Ultimate RON98..... sit down boys....
did 445.3k using 34.2litre or 7.68L/100k or 13.02K/L (sit down now) or 36.7MPG............ my previous best was 8.36L/100k from an unflashed MH7203..... 100% highway cycle @ 100-110kph.

Just incase "Knock Values" nothing over 1, excuse me if I grin

Ok Kitty, spill the beans what have you changed in the maps or did someone else do the mapping.

Great result though, my best at 70mph was 32mpg. but that should get better at 62mph (100Kph). however i have never been able to drive that slow on a motorway for any length of time to prove it. 140miles at 70mph was hard enough i had to be so careful to keep it off boost, it was some of the hardest driving i have ever done, the consentration required was imense. It was done on relitivly flat roads as well manchester to warwirck way on the M6, M5, M42, M40.

[Kitty's VR4]

LOL, Not giving to much away at this point, early days yet, basically changed the fuel maps, added extra spark maps, changed the timing by a few deg in the 2100rpm-3200rpm range, tuned to run on our 98RON fuel and a few extra bits and pieces, no boost changes on this particular ecu at this point. These are more courtesy post's to let you guys know the MH7203 is now flashable with the beta version of ecuflash...... So it's time for you guys in the mother country to extract your digits and play catch up with the convicts, just as we are having to play catch up with the MH7201 ECU reflash !!

The 100% highway figure relate to my previous figures 8.36L/100K, todays figures where with a bit of everything, highway, bumper to bumper in Sydney traffic, some mountain twisties. The elevation was from just under 900metres, down to about 20metres above sea level and back home to the 800metre elevation.. oh and a blat to test that speed limiter changes worked.

Tomorrow I'll be doing a 200km run to canberra and back that will be 100% highway cycle, I'll post the figures up tomorrow night in case you interested.

[SGHOM]

All the above is a load of borrox.

Truer mpg should be monitored over a period of weeks or months, not on one trip..... Long or short.

I have the benefit of a trip computer in my saaaab, & believe me.... I'm like driving miss daisy nowadays .... Ferrying old folk around!

I've not reset it since Easter, & I'm currently getting 20.1 mpg. & that from a 2.0 ltr lpt.

This begs the question ....... Can a trip computer be retro fitted ??

[Kitty's VR4]

Actually Derek, thats fairly true, I have records for the 9,000k I've travelled since owning the VR4, averaged figure is 9.87L/100k. Todays logging exercise wasn't about getting the best fuel economy, it was about logging whats happening across a full set of driving conditions, tomorrow is about economy, but the main thing is that there is noticable improvement in economy.

I just thought you guys would appreciate the heads up.

[Davezj]

all info is good for mapping kitty.

just let us know what you have done to edit your tables and what the startard tables are. we can see if they are close to what we have in our ECU. i am assuming the 7203 will have a newer base map than the 7202 has to begin with then you have changed these to get to where you are now.

should be interesting. i am not able to remap my ecu at the moment but i know a lot of people are and the info will be greatly received .

i know of at least one person that has leaned out the fuel maps across the board and changed the fuel cut table and is running 18psi with no problems and i believe he is monitoring his AFR correctly as well. so it would be interesting to see how yor changes differ from his.

[Kitty's VR4]

There is very little difference between the 7202 and 7203 (some extra spark maps and a few minor tweaks)

When a complete base tune is ready for publication, it will be available on OzVR4, and I'll paste the link here on CVR4, guys don't take this the wrong way but I'd have my throat cut if I did this any other way!!!

You guy's had the march on the MH7201 and I haven't seen that being made publically available !!

If you'd prefer that I pack up my bat and ball and not let you know whats going on then I'll continue paying my membership sit in the corner and shut up!!

[Kieran]

When a complete base tune is ready for publication, it will be available on OzVR4, and I'll paste the link here on CVR4, guys don't take this the wrong way but I'd have my throat cut if I did this any other way!!!

You guy's had the march on the MH7201 and I haven't seen that being made publically available !!

If you'd prefer that I pack up my bat and ball and not let you know whats going on then I'll continue paying my membership sit in the corner and shut up!!

Understand your position, Kat.

And are we having a bad day, perchance? :ranton:

[ianturbo]

Last year goin to Gt yarmth i got 320 miles out of a tank full ,how to work that out in MPG i aint got a clue but i thought it was good !!/notworthy
ian

[BraindG]

ive just come back from two trips, to and from glasgow.

223 miles each way, both ways light was on when i arrived at my destination.

i used to get to perth on a full tank :P

Maybe a service is required, although min speed was 90.

[mattnz]

So the revelation is that going slightly slower will get you better fuel economy? Incredible :/

[phosty]

There is very little difference between the 7202 and 7203 (some extra spark maps and a few minor tweaks)

Do you mean there are more than the twin pair (i.e. 4 total) of Hi/Lo timing maps that the 7202/7201 has (ignoring the cat warmup tables)?

Interesting if so.

[Davezj]

There is very little difference between the 7202 and 7203 (some extra spark maps and a few minor tweaks)

When a complete base tune is ready for publication, it will be available on OzVR4, and I'll paste the link here on CVR4, guys don't take this the wrong way but I'd have my throat cut if I did this any other way!!!

You guy's had the march on the MH7201 and I haven't seen that being made publically available !!

If you'd prefer that I pack up my bat and ball and not let you know whats going on then I'll continue paying my membership sit in the corner and shut up!!

i totally understand this from your point of view. i am just interested. even if you spelled it out to me i probably would not understand it as i am no flasher (pardon the pun).
when your ready to show your hand one way or another i am sure we will all be interested.
i have subscribed to this thread so any little tit bits of info will be mused over with interest.

[Dom B]

So the revelation is that going slightly slower will get you better fuel economy? Incredible :/

Not that simple Mattnz, i also found that going at less than 60mph, the mpg dropped like a stone again as the engine was being either worked harder against 5th gear or was revving more in 4th. 68mph seems to be the sweet spot for my car. Its a trade off between moving at a p;ace to eat up miles but at a speed that doesn't have the air resistance too high or the revs/boost too high all the while trying to stay at the engines design point which on most cars is 2500-3500rpm.

You can get the turbos to boost much earlier under load in a higher gear than you can under little load at a slightly higher speed. You may have noticed that when mapping a car for boost you can't really get any boost by just revving the car when stationary you have to drive it or have it loaded on rollers before the boost gauge will read full figures.

[Dom B]

With all this decoding and re-flashing work going on everywhere i am interested in how people are doing it. Are you desoldering the eerpoms from the boards and reading them in a raw form i.e. a simple binary file then by just trail and error trying to figure out the shape of the memory map and table locations then trying to identify which table is which by a bit of educated guessing. Or are you able to get all the data out of the mut port. Also what software are you using to manipulate the data and reflash it to test it.

[Turbo_Steve]

With all this decoding and re-flashing work going on everywhere i am interested in how people are doing it. Are you desoldering the eerpoms from the boards and reading them in a raw form i.e. a simple binary file then by just trail and error trying to figure out the shape of the memory map and table locations then trying to identify which table is which by a bit of educated guessing. Or are you able to get all the data out of the mut port. Also what software are you using to manipulate the data and reflash it to test it.

Unhelpfully, the answer is "Yes" to all of the above!

[wintertidenz]

The 7201's are flashed by desoldering and resoldering the flash memory onto the boards.
7202 and 7203 are flashed through the MUT port with an OpenScan 2.0 cable and Evoscan. It's then reflashed using EcuFlash.

The maps are read in hex and then an XML file is generated to map out where everything is, there is still a lot left to map for our cars though.

[mattnz]

What's involved in flashing for economy? Does it have to be done for each individual car, or is there a base tune floating around that will work reasonably for everyone?

[Beastlee]

I did a full tank fill-up before going to Full Speed in Holland on the 9th May. I was pleasantly surprised to only need to fill up on Saturday and promptly put 30l back in. I too use Road Trip to log my fill-ups and I was even happier to find that I had managed 238miles and still had over 12l left in the tank. I've guesstimated at 15L remaining based on where th guage ended up after a 30L top-up. Using this figure I did 238 miles to 45L which works out to approx 24mpg. Given a 12mile 100mph + run and a week of going to and from work that's a 7mpg improvement on my normal figures. The only thing other than the run that's different is I have the stock BOV on....

[Turbo_Steve]

The BOV can make a HUGE difference, Lee. It took mine from 20mpg - 23/24mpg.

I still found myself wondering where the rest of my bhp was, though :)

[miller]

I too use Road Trip to log my fill-ups

Is that an online based application?

[Beastlee]

Sorry, got crossed threads (see what happens when you search!) It's great iPhone/iPod Touch app that logs fuel and other costs for multiple cars and can give you some excellent reports. It's perfect for things like Ring trips.

What sort of effect is a VTA likely to have on economy? I'm guessing it will be worse as I can smell the fuel wastage now.

[Beastlee]

Sorry to dig this one back up but it was the first fuel economy related thread I found in which I'd posted before.

Took the car down to the Black Forest last week, 300 mile trip, was driving between 80-100mph for the majority of the way and started out with a full-tank, 30L extra fuel, 2 passengers + me and our luggage, etc for a week (the two passengers were women so you can estimate how much luggage :P). Gave it a lot of beans down there and mostly town driving, the journey back was almost the same except for a 15 mile trip down into the Mosel Valley and back up again which seemed to use a quarter tank on it's own! Total MPG was 26.7mpg but i caculated the run down as being about 32mpg! That's almost twice my average. I was pleasantly suprised to fins I can get 300+ miles to a tank if I go on a run. Germany has just become a little smaller :)

[phosty]

Did you note how the AFRs were looking while cruising? I assume it was floating around 15.1-15.3 or more to achieve those consumption figures. Now if we could identify the tables / switch points in the ECU roms which control the 'lean burn' modes we should be able to improve consumption at lower speeds too.

[Beastlee]

I have my Wideband set to emulate 15.2 so I imagine they were pretty much around there. Didn't bother looking much.

[Wodjno]

I have my Wideband set to emulate 15.2 so I imagine they were pretty much around there. Didn't bother looking much.

Don't you know where the Record Button is o the E-01 /pan
:p

[andyleaves]

The BOV can make a HUGE difference, Lee. It took mine from 20mpg - 23/24mpg.

I still found myself wondering where the rest of my bhp was, though :)

Steve, am I reading this right?

An uprated BOV should not only improve power, but may also help econ?
It which case which BOV are you running?

[bradc]

A vent to air bov or a leaking stock bov can use a lot of extra fuel. The best bet is a good recirculating bov like the EVO 8 MR metal one.

[Atik]

I've just managed to drive 342 miles on one tank and the fuel light hasnt begun to flicker yet. That is pretty much ALL motorway mileage with no real hard boosting. The outward journey was an average of around 80-85mph. The return journey was a load of crap. M25 stop start for about 15 miles and almost a permanent 45-50mph along the remaining part of the journey due to the bad weather. I havent filled up the tank yet so cant give you a proper mpg reading, but I was well chuffed at managing 342miles getting home without a pitstop!

[bradc]

558km without a fuel light, that is pretty bloody good dude!

[Beastlee]

558km without a fuel light, that is pretty bloody good dude!

Only just get 630km out of the works diesel, I am averaging 130km/h for the entire journey though :)

[Ryan]

558km without a fuel light, that is pretty bloody good dude!

How did you calculate 558km? 342 miles is 547.2km (342 x 1.6)? Even if we used 324 x 1.609344 one still arrives at 550km

[bradc]

I'm unsure. I normally do miles / .6125, must have mistyped


edit: Yes I did, I think I did 342 / 0.6215 which is 558.4km, rather than 0.6125 which is 550.3km

[Ryan]

Ah - that explains it, was just curious :2thumbsup I managed 560km with about 120km of that city driving - then I ran out of fuel :( I will hopefully better that in a couple of weeks.

[Atik]

So I need 13km before I fill up to beat your record Ryan? :p

[Ryan]

Well it's not really a "record" Atik, especially as I effectively stranded myself at the roadside :p

[bradc]

Myself and Wodj are members of the 600km+ club too remember.

[Beastlee]

If I ever get around to mapping the EMB (now fitted for over 2 years) I am hoping things will get even better.

[Atik]

Eek! 600km (372miles) will probably be a bit too much for me. I managed another 12 miles on that 342miles last night. The fuel light began to flicker at around 348 and is now coming on when on an uphill slope. I normally manage to fill around 51litres at this stage, but I'm determined to get a few more miles out of it :D

[bradc]

You will be fine as long as you don't go uphill :) You've got around 7-12 litres left at the moment.

[Ryan]

Ja I've been driving around on what I thought was the end of my tank until yesterday.

When I start the car at home (flat surface) the light stayed off for a little while and then came on after about a minute or so. This car's fuel gauge is different to my previous one in that my needle can go slightly beyond the empty mark before I have 10 litres left.

When I filled up yesterday, I put in 50 litres so I agree with Brad that you should be able to go a little bit further, especially considering that yours is manual. :)

And yes - the uphill was my car's Kryptonite on that fateful trip home, i could have made it otherwise (was about 1km from home!)

[Wodjno]

Eek! 600km (372miles) will probably be a bit too much for me. I managed another 12 miles on that 342miles last night. The fuel light began to flicker at around 348 and is now coming on when on an uphill slope. I normally manage to fill around 51litres at this stage, but I'm determined to get a few more miles out of it :D

I'm normally at around the 57+ litre mark before i have to shake the fuel into the engine :uhoh2:

..DATE.. Miles.Gallons.Price PG.MPG
8/10/10 281.0 12.530 £5.35 22.4
8/03/10 268.0 12.260 £5.35 21.9

7/22/10 280.8 12.522 £5.31 22.4

7/12/10 291.8 12.290 £5.35 23.7

7/02/10 368.0 12.398 £5.58 29.7
6/19/10 228.0 11.510 £5.58 19.8
6/07/10 278.7 12.797 £5.58 21.8

PS.. I once squeezed 61 litres in my Auto VR4 /help

[dickytim]

I thought 10.9 l/100km was pretty good.

looks like I have been driving too slowly.

And I need a remap :)

[dickytim]

I thought 10.9 l/100km was pretty good.

looks like I have been driving too slowly.

And I need a remap :)

Gave it the beans this tank, and also boost issues (freaking Hyper)

12.2l/100km, still a hell of a lot more economical than my other VR4 (and Stacey's cars)

[ersanalamin]

Myself and Wodj are members of the 600km+ club too remember.

Brad, how do you manage to get 600 km+ for VR4 fuel consumption? was it for regular driving? I have a problem with fuel consumption right now, could u please give me any tips/advice? what your set up right now?

[bradc]

Just driving long distances, not making boost, thats about it really.

[Wodjno]

This reminds me.. I really should get my Wideband 02 adjusted.. Just hope it doesn't affect my MOT today /Hmmm

[The Vee]

Just driving long distances, not making boost, thats about it really.

Spot on.
Had 35+ out of mine doing the same
Also had 21s round town!!
Tis only FWD though

[The Vee]

This reminds me.. I really should get my Wideband 02 adjusted.. Just hope it doesn't affect my MOT today /Hmmm

Mine did. Had mine running 15.03 and MOT machine no likey. Very little tolerance unfortunately