Power Commander for the Digifant

[Dogpilot]

My chief Inspector (aircraft, ex racer) told me to look into the power commander for motorcycles to overlay on the digifant. It basicly lets you custom bias the sensors to adjust mixture, add real time leaning and adjusted ignition from a little box. It goes inline to your temp, hall and AFM and tricks the system. Most motorcycles use some variation to get increased performance:
http://www.powercommander.com/

Just food for discussion.

Cheers,
James
_________________
Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[Phil G]

Right, and then there is UniChip North America -
http://www.unichip.us/unichip_home.asp

. . . and their South African parent company Dasek -
http://www.dastek.co.za/

Check out the 'Company profile' , there's a blue Vanagon right in front of the main entrance to the place . . It's a good bet someone there knows what a Vanagon is.

[Ericthenorse]

I had a Power commander on my Buell for a while... They work great, but it didn't agree with the computer.. (made by VDO) I have ridden other bikes with it installed and they have had no problems... Give it a try... If you can figure it out, I will stuff mine in the van...
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'69 bug--rusty as hell
'91 vanagon carrat-slammed,5 speed,4 wheel disks,17x8.5's

[Dogpilot]

The unichip looks promising, but the year range ends at 1996. So I suspect, but could not confirm, it wants to see knock sensing. I may request more info.

The power commander does not need knock sensing, as most motorcycles don't have it. My inspector rides a Ducati 999, which requires premium to run, has a sophisticated ecu, makes a ridicules amount of Hp, but no knock sensor!

Reprogramming the chip, is always an option, but only on the -D part number ECU. It has a removable eprom.

Up here at altitude (7,000') the van tends to run rich. If you tune it perfectly here, you run the risk of being too lean at SL. I guess the Digifant's ability to adjust the O2 map is limited.

Cheers,
james
_________________
Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[r39o]

James,

! bet if you diddle with the some added resistance in the AFM circuit or the internal outside air temp thermistor inside the AFM (Sensor I) you may well be able to affect your mixture. Call it a poor man's Vanagon Unichip!

Then again, you may, via an OP AMP, offset the signal coming in via the O2 sensor. You could get extra fancy and program a PIC to play games for you too. Again, another poor man's solution.

-Walt...
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"Use the SEARCH, Luke" But first visit the Vanagon FAQ!

1990 Multivan EJ 22, Rancho trans 0.82 4th, Small Car front AC, CLKs w/ 215/65-16, homemade big brakes 303mm, Konis, Recaros, etc....

Click to see my ads for Cup holders, Subaru clutch fix and CLK wheels (no wheels currently)

[Dogpilot]

The concept of on the fly tuning came up duing my last visit to the shop. Thats how the subject of the power commander came up. Not a big deal to put a millivolt readout on the O2, and a bias resistor on the AFM. He was suggesting, why not go all the way, its what the motorcycle world has been doing for some time now. The factory tunes for the EPA, you can tune for performance at a flip of a switch. Not that there is a huge margin available in the 2.1L or the 1.9 before the self destruct sequence kicks in.

Cheers,
james
_________________
Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[Phil G]

I'm a big fan of knock sensing for automotive management systems for many reasons. A few are:
1. Unlike bikes, cars and trucks are much heavier with fewer gears to select and can place much greater low RPM loads on a motor - the condition under which 'knock' commonly occurs.
2. Crappier fuel may be used when needed that would be detrimental only to power, not reliability.
3. A lean map could be chosen on the fly without harm to the motor when an increase in fuel mileage was desired.
4. In turbo applications it can be a real lifesaver where boost is regulated by the management system.

Would it not be possible to install in the Vanagon, the brain from a VW model using Digi II that included knock sensing? Installing the sensor itself is nothing.

I see that while Unichip's on-line model application list as you say is for later models, they also state somewhere else on the Dasek site "virtually any EFI application" They are also a South African company where there are plenty of Vanagons. I would actually be surprised if Digi I & II aren't supported. And it may well be the case that knock sensing is simply added and supported by the Unichip, making unnecessary a brain that was 'knock sensing aware'.

My interest in such a product is related to turbocharging. If there is a way to economically modify the existing management system to accommodate software re-programming and the addition of sensors/controls such as boost management, knock sensing, and Alcohol injection, a ton of money could be saved by not having to replace the system. Besides, the Digifant system can provide very accurate mixtures in relation to the operating environment. CIS-E is also very accurate with tons of used stuff out there, but physically it’s a very complicated system to plumb into a non-CIS vehicle, and not as easy to add accessory sensing or control features to.

[Dogpilot]

Phil,

I really agree on the knock sensing aspect. It can do wonders on the fuel management, and probably add a mile or two to each gallon burned. The existing map is safe and sensible. Apparently, GoWesty has diddled with the digifant II retrofit. To completely redo the map from lets say a Golf GTI's chip to a vanagon's would take a programmer a lot of time, a vehicle and access to a dyno. ie MONEY.

It is much eaiser toget a computer simulator for the later OBDII style computers. I have looked for a digifant simulator, only to come up empty on Google.

Yes maybe a query to SA would be in order. It would seem that an overlay system might be eaiser to impiment than a complete system transplant. Apparenly, I was told, but have not found it yet, there is a spot in the head for the knock sensor to be installed.

I agree CIS is a great system, but you would have to completly redesign the intake system, ahhhh.

Now here is where the Subi crowd can kick in. Yeah, get a subi, it has all this. I know, I know, but like I've said before, I also fly a 54 year old airplane that can be outrun by the van if the wind is just so. A little diddling might improve things just enough to make it better.

This is really a great forum, kind of like the Borg on Star Trek, a collective intelligence.

Cheers,
james
_________________
Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[Phil G]

Resistance is futile, my friend . . . .

[sc-surfer]

Wow. You guys are charting some new teritory. It is kinda' out of my league technically, but if someone could come up with a better computer, esp. one with a knock sensor, I would gladly pay a reasonable fee. That seems to be one of the main things keeping the 2.1l in the dark ages. Like many others here, I prefer to keep my VW a VW. But I'm not opposed to making every possible improvement.
_________________
'89 Syncro Westy
Catalog of Vans at SDM 2010
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