ECU Mappings

[ewenm]

With the every increasing number of PDAs and miniature computers around, something has been preying on my mind recently...

 

Many Caterham (or similar-car-type) drivers have one car used on both road and track. On the road, typically the revs will use the whole range so a fairly flexible, broad torque band is useful. However on the track the revs will almost always be up at the higher, maximum power end. To get the best from both situations it may be beneficial to have different ECU mappings. (Plus perhaps a special "emissions" mapping for MOT time...)

 

1st question - is the above accurate? - would different mappings help?

2nd question - how about holding different mapping files on a handheld PC and downloading to the ECU them as required?

3rd question - going a bit blue sky here... Why not have a slot on the dash to accept a flash card or similar mini-memory device for instant mapping changes?

 

Now having seen the film "Fast and Furious" with a silly scene showing a mapping being adjusted on the fly while drag racing, is it possible to change an ECU mapping while the car is running? I reckon it'd cause all sorts of engine probs.

 

Purely theoretical of course

 

Ewen Malloch

P979TMV - Yellow 1.6 K Series

[ChrisC]

Hi Ewenm

 

It would be possible to write a map download program for a Pocket PC device, but I think it would be better just to use a Laptop and save the effort.

 

“Fast and Furious” very Max Power. 😳

 

 

Chris....

H15 SVN Get it !

[V7 SLR]

You need to read Dave Walker's book on engine management. It's brilliant and understandable by any enthusiast.

 

In a nutshell if the engine's mapped properly then you shouldn't need to mess about with it for different power requirements. There are enough load and speed sites to provide accurate-enough fuelling and ignition across the whole rev range.

 

There may be a case for mapping slightly leaner to satisfy MoT requirements, but I'm not 100% certain what I'm talking about here. I'm about to have my engine remapped (March) at which time I'll want a "power" map and one which satisfies the MoT. That last one will be done in conjunction with the closed loop settings on the M3DK and my removable cat (which will be re-inserted for this purpose only).

 

A brief chat with DW at the Autosport led me to believe that the MoT is only concerned with ommissions at idle and 3000rpm so we will probably hack my "power" map (if necessary) to provide suitable emmissions at these revs.

 

With regards to how you store and upload your map, the problem where the Emerald is concerned is that the software is PC based only. I've asked about it being ported to Windows CE or Palm OS but this will require a re-write apparently and Emerald as so successful they are flat out busy. Good for them..!!

 

Having the hardware installed to enable you to use a pc card or similar only seems like technology for the sake of it. If you really want to be able to swap maps cleanly and easily then having a bit of extra memory in the ECU itself and a little switch on the dash would be more sensible. There's no way that you'd ever need more than 2 maps in a hurry (assuming the MoT map really is different to the power map). For all other cases, the PC upload appears to be the most sensible.

 

In the meantime, mapping whilst on the fly is possible with the Emerald (this is exactly how DW does it on the rolling road) but on the road is another thing entirely. You would need to know the emmissions produced and have the ability to hold the car at a certain load/speed site so unless you have a hill of known and consistent gradient, then it's all pointless.

 

That said, minor tweeks can be done on the road if you feel you have a deficit in the map somewhere, but as with all things Hollywood, their representation of this is utter bull. If you have a good map, you can't possibly improve upon it. Messing with it will only make it worse. My experience of Emerald (sorry to hark on about them) is that you come away with a map that's not worth messing with.

 

Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours

 

[Anthony]

Hi V7SLR, did DW give an indication of the likely set up costs ?

 

Regards

[Anthony]

Hi V7SLR, did DW give an indication of the likely set up costs ?

 

Regards

[V7 SLR]

Completely depends on your engine spec and whether he has a map which is a "good start". As there are lots of K's about with lots of different maps I have never needed more than 4 hours to tweek a previous map to work 100% perfectly with my engine. His rates are very low. Last time I was there it was £40/hour plus vat, but I couldn't comment on whether that price is still current.

 

To me it's worth the money just to hang around and see what's happening in the Emerald garage for a day. You learn a lot just being there, and I come away feeling like I've just had the bargain of the century.

 

Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours

 

[scooby dooby doo]

and you learn a bit on how to map it. so you can do your own tweaks if you notice a flat spot or whatever.

 

HOOPY 500 kg R706KGU

[CHRIS CLARK]

............and you also learn that most of the 'K' maps floating around have 45% acceleration fueling set into them and nobody much seems to change it. 10-15% is actually much better!!!!

 

Clamshell Club Founder Member.

[Mick Day]

If you want two maps & have enough money floating araound for extra toys why not just buy another ECU!

 

Mick