VEMS engine management

[Keeper of The Kitten]

And Newmarket is not that far for me either!

[rob@vems.co.uk]

So I take it there's not a U.K based Audi car at the moment then Rob?

Well would be good if you could get all the information from Peter and Kalsket and come up with an out of the box solution.

No theres not a running car in the UK yet, but judging by the level of interest its only a matter of time until we get one going. The information from the developers and Kalsket is as available to me as my Nissan information is to them

[Cullam3n]

And Newmarket is not that far for me either!

Stone's throw from the a11 for me

[Bram]

You can make it good in just couple of starts, but if you want perfection (enough fuel but not a cc that isn't needed) will take time.

When ever you want 400++ (limit for std maf), remap is no longer a good option. Up to 400 it is. If you buy your vems from www.vems.co.uk the base setup you get will most likely be based on months of my blood, sweat and tears.

Are you sure 400+ is the limit for the standard MAF hotwire or is it the limit because the diameter of the pipe? I thought a few people here run standard MAF and have more HP then 400?

[A80Avant]

standard maf can be good for up to 450ish.After that it can still be used,but wont be taken into the equation as it reaches it's limit in volts and you go by experience in mapping thereafter.However that is not only the issue.In Greece there was an RS2 made once around 550hp with 2 extra injectors, some hybrid KKK29 back then and standard MAF....only the MAF needed replacement every couple of months due to sucking of the wire or other malfunction...

[zlobo]

we run 700hp++ on an modified s2 maf

[A80Avant]

the question is ... what modified S2 MAF is that? which modification was it done? how easy to do if this one malfunctions?

[zlobo]

the question is ... what modified S2 MAF is that? which modification was it done? how easy to do if this one malfunctions?

You need to make the maff pipe bigger.. you replace it wit an 3,5" pipe or bigger.. you also need to do a remap after that. we did it in forsbergs car and he have over 700hp

this year it will even get more.

an other way is a bmw m5 maf or spq maf

[A80Avant]

What do you do if that MAF sensor you have used goes bad? you have to buy a new maf,detach the new sensor without destroying it,and put it in the fabricated pipe. The problem is that it is not an easy task to do that with the old mafs,where the new ones have detachable sensors you can replace.
Has anyone tried a fabrication like that with an RS4 Maf for example?

[zlobo]

What do you do if that MAF sensor you have used goes bad? you have to buy a new maf,detach the new sensor without destroying it,and put it in the fabricated pipe. The problem is that it is not an easy task to do that with the old mafs,where the new ones have detachable sensors you can replace.
Has anyone tried a fabrication like that with an RS4 Maf for example?

then i replace it yes i have to get a new maf and carfully remove it an put it in.

[A80Avant]

although someone else told me that it is not difficult to to,i concider something like this easy if it had x number of screws to take off and put back in.Anything other seems complex to me to have to do quite often(as these tend to go bad often).
That is why i was concidering a newer type MAF.
Anyone ever tried or concidered something like this?

[Jamo]

Think people misunderstand the limit of the MAF.

Papvas hit the nail on the head earlier

standard maf can be good for up to 450ish.After that it can still be used,but wont be taken into the equation as it reaches it's limit in volts and you go by experience in mapping thereafter.

The MAF registers air mass on a scale on 0-5 volts. When you get above 400-450 bhp you max out the MAF in terms of air mass and it reports 5 volts i.e it's maximum range.

When this happens the Mapper must map the car by skill alone as the MAF input is useless as it's maxed out at maximum voltage.

Therefore it is possbile to run a MAF car up to 700 bhp as Zlobo has reported however the MAF becomes redundant in use once it hits the 5 volt limit.

[A80Avant]

excactly.What happens when the tubular pipe is bigger,is that you basically manage to get more than 450hp before the volts reach the 5 figure.This is why you are able to still keep the maf in the equation.However we still come back to the question of being able to have a maf that can get you more than 450hp AND still be easy enough to replace it when damaged.
It would be nice to have one of the mapping gurus give us their input on that...

For me having the SQ MAF is not an option as it is very expensive as it is to find,AND as it is old it may become obsolete.So this is why im thinking about newer models.

[S2central.net]

This is why the same MAF sensor can be placed in a bigger housing (larger diameter) to allow its useful dynamic range to be extended over the 0-5V output it provides. Only trouble here is that you need to calibrate the MAF so as to plot a curve of air mass flow against output voltage... Then you have a reference point to program with.

The other thing is that the MAF output isn't linear - this is to provide for lots of detailed info at part throttle for smooth driving character, best emissions and such.

MOst aftermarket systems just ignore the MAF because of this complexity and opt for MAP and TPS instead.

[S2central.net]

If I was gonna keep the MAF, I'd go for some of the Bosch Hot Film types used in diesel engines. There is actually some decent published data on them - I 'll have to dig it up, but Google could get it against 'HFM5' or similar... There must be a big enough one to use and these are hot FILM - not the more fragile hot WIRE type... May or may not be plug and play, but shouldn't be rocket science to graft onto aftermarket system.

I prefer to use MAF as you get a true reflection of the air MASS being drawn into the engine with automatic temp compensation along the way. MAP & TPS are just estimates of course.