VersaTune User Forum

They were adding the deviation instead of substracting it. If the deviation is negative then you want to actually add it to the lambda value (negative deviation need another - sign to become +). And the other way around for positive deviation, means that the ECU actually sprays less fuel to meet the target AFR so that deviation needs to be substracted from the initial value.

Sorry guys, forgot to post this up when I wrote my own calibration script...

P.S.: when the VT guys added that Russian language section I first thought the site was hacked!

Do you guys flash your desired tune to the car before doing a maf cal or do you leave it stock tune and then copy the maf cal table 'to' your desired tune for flashing or does it not matter?

Doesn't matter, as long as you copy the tables over when you change tunes.

Ok, is there an easier way to do the MAF cal? I'm using a stock intake and I've spent 7-8hours in excel spreadsheets and still got naf all filled in the MAF correction table. Is there an easier way to do this or am I being too padantic. Oh btw how the hell do you blend the gaps in the table??? Is there a way to do so... I also have no points of reference for MAF voltages higher than 3.3v as once over that it drops the LTFT and STFT's to zero. Is this due to enrichment? Thats holding the throttle and revs steady at that MAF voltage to get a stable reading too.

HELP ME I'm sooo lost.

Stock intake doesn't need a maf cal
But for future reference, when you hit ol just use the desired v actual for your cell multiplier.

I'm wondering if the stock MAF cal for the US-spec versus euro/AUS spec cars is the same.

It should be the same... I guess!

Sent from my Classic EVO!

Probably, but I'm not sure. At some point the US gas was lower quality but had more ethanol (6 to 10% standard) in it which made it more resistant to knock issues (so people were getting more power form advance timing rather than pure caloric energy). While the gas in Europe has 4-5% ethanol (and no more than 5%, they want to make it 10% but there's a problem with even the newer cars manufactured after year 2000 that would not support so much ethanol because of the materials their in-tank fuel pumps and other fuel lines/hoses are manufactured from).

In australia there is apparently no ethanol in our 98+ blended fuels from BP and Shell yet a number of other chains do sell 5% blend and 10% blend but are required by law to show that blend in the grade of the fuel at the pump. So for example at Caltex's here we see 'Standard Unleaded' - no ethanol - less than 90 octane, 'Premium unleaded 5%' - 5% ethanol - 94 octane, and 'Ultimate 10%' - 10% ethanol - 98 octane.
Some problems we've had here is the ethanol blends taking in alot of water in the older service stations. I work at a mechanical workshop on the fringes of a city and we see cars in all the time running ethanol blends from independent servos that look like the fuel tank has honestly been in the ocean for a number of years. But they save 2 cents a litre!
So is ethanol in the european fuels a standard or is it labelled separately as it is here?
I had completely avoided the 100 octane 10% ethanol blends since loading in the HIgh Load tune as a general precaution, not that I put it in much, always use BP Ultimate 98. I wonder then if there's gains to be had in using the 100 octane ethanol blend? Just a bugger that the only servos that sell that in australia are the dodgy independents that serve out dirty gas.

Since the percentage of ethanol is 5% max they just sell it as 100/101RON gas and there's a sticker at the gas station stating that the fuel may contain up to 5% ethanol. They use some other additives to raise up the octane but we don't really have any high octane gas with 0% ethanol.