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VEMS
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Racing  



Joined: 27 Apr 2004
Posts: 374

PostPosted: Tue Sep 20, 2005 6:21 pm    Post subject: VEMS Reply with quote

So guys.
My VEMS finally showed up.
(Versatile Engine Management System)
As i´m amidst a move of the shop the install will have to wait a little,but i´ve at least played around with the software a bit.
I know that some of you guys have looked into getting a VEMS,so i thought i´d give you my first impressions.
It IS a beta.In other words it seems to hang on my old POS lap-top on occasion.

None the less.
Looking through the maps you soon realize that there is a poss to adjust target O2 values for more or less every existant load point.
In other words..you can tell the VEMS to chase basically any target lambda value at ANY load.
(Example-You can tell the ECU to chase an AFR of 12,7@ max torq and 13 flat@ max power as well as 16,0@ light load/cruise)
What´s more it seems that this info can be interfaced with EGT values to boot.
In other words you´re able to tell the ECU what exhaust temp to look for as well,and as a result the ECU will basically from a practical standpoint learn the entire curve by itself.

No idea how it works in practice as that remains to be seen.

Another USABLE feature seems to be the interpolarization of running the ECU in alpha numerical vs speed density.
In plain english that means that you can let the throttle position sensor control the ECU with wild cams and low vaccum at for instance idle,and at a given load point reverse that into letting the MAP sensor take control-in the normal manner-under load.
This is GOOD thinking when running wild cams and boost for instance.
Interpolarization between cells seems good,altho i for one could have used more of the individual cells.(There are 9,and i would have wished for 16 no doubt)

Apart from that the build up seems straightforward enough.

Pricing is most def right,and the VEMS can be bought either as a kit or as a ready built unit for flying lead.
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Raceboy  



Joined: 01 Mar 2004
Posts: 2326
Location: Estonia, Europe

PostPosted: Wed Sep 21, 2005 12:00 am    Post subject: Reply with quote

Excellent news! Just in time too, as my engine is beginning to take it's desired shape and soon is in need for some serious (versatile) engine management
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'84 928 S, sold
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MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Sun Oct 02, 2005 3:54 pm    Post subject: Reply with quote

what is this system ive never heard of it. How much is it?
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Sun Oct 02, 2005 4:13 pm    Post subject: Reply with quote

I hadn't heard of it eather but after doing a little research it sounds like one heck of a system if lives up to the hype and promises! If anyone here can ring it out and give an honest assesment it will be Racing!!

Todd
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Racing  



Joined: 27 Apr 2004
Posts: 374

PostPosted: Sun Oct 02, 2005 7:04 pm    Post subject: Reply with quote

VEMS is basically a an internet spin off of the old megasquirt in a sense.
Only...it´s WAY more high tech in every aspect.
As stated it´s a sort of joint project that has had people involved more or less from all over the world.
Mostly so from the high end of the old DIY EFI group.
The internet at its best

I´ve been updated on this since a while back(approx a little more than a year) as one of the more involved boys is a close personal friend that i´ve worked with on other joint projects.(WB O2 management amongst others)
A guy by the name of Jörgen that´s a phenomenal designer of digital circuitry hardware.

http://www.vems-group.org/

Cost is just a tad more than the old MS systems,but boy....is it worth it...

As far as i can see these guys haven´t prduced a copy of the high end systems any more...they friggin took the lead.
..and at a cost.. ..that keeps this in the right perspective.
This time out they´ve been anal about keepin the project under covers until the had a reasonable product not to be ripped off.

Idea is that you can basically purchase th VEMS in more or less any state.
Complete,ready to run,or to solder and assemble yourself.
Your choice.

I´ve been handed a beta unit(mainly as hardware/firmware) to tell the boys what i think of it,and yes...mainly so as Jörgen knows that i´ve had my fat a-s into this stuff as a tuner manyfold over the yrs.

Idea is to have it control the mercedes cosworth engine with the rather large garret huffer.

Setup is as follows;
Basically stock mercedes cosworth engine.
Forged crank n rods-new bolts aso.
OEM forged Mahle slugs turned down in the lathe by 1,2mm to reach a true static compression of 9,2:1.
The gem of a cylinder head is more or less untouched.Cleaned up(the little needed)and overhauled with new guides asf.
Entire intake/exhaust system is tossed out the door.
New intake as been fabbed,and injectors are two rows.
Intake is a´la the old Audi Sport.Ie;Diffusor plenum mating to the main plenum-to avoid pressure fluctuations as best as we can.
Intercooler is -as on my 931-made to fit.
1st row of injectors is a set of Siemens 630cc ones and the 2nd is a set of Bosch 390s.
VEMS will run them both.
However..at first we´ll have to manage with the 1st row as the staging software isn´t worth a damn at the moment.No prob tho as it´s solely a matter of new info for the flash mem.

Throttle is the OEM mercedes 65mm unit.Just relocated a "little"

Exhaust is basically an upside down OEM cossie unit that we´ve modded from there to the huffer that´s placed in the right hand front inner fender.
Huffer inducer is at 65mm,and the compressor reaches its limit at around 650 honest ones.
Gonna run just a tad over 1 bar boost for starters tho,and as a result we hope to pass the 400 mark.

WG is a 50mm HKS unit,and the BOV is homebrew by a set of locals(the boyz with the opel for those that remember)
Apart from that...the stock dogleg trans and stock rear.
Yeah...we´ve lightened the flywheel severely and run a sintered disc.

This little project´s been on the afterburner a little due to us moving the shop,but as that´s done as of this friday..(right peep )..yeah well..not much keepin us anymore.
So..
Results coming up.

Cheers.
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Mon Oct 03, 2005 3:57 am    Post subject: Reply with quote

Pretty cool! The thing I like best about the VEMS is its "self learning" ability. If it is capable of doing this on a HP boosted application without melting it down I think it will eventually win over several MS users as time goes by.

Todd
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Tigger937  



Joined: 11 Apr 2004
Posts: 914

PostPosted: Mon Oct 03, 2005 4:08 am    Post subject: Reply with quote

Any potential for use in a 931 application?
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Mon Oct 03, 2005 10:41 am    Post subject: Reply with quote

This would be tits for a 931! But you will need to convert the rest of the system to EFI. It will not work with the stock Injection system.

Todd
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Tigger937  



Joined: 11 Apr 2004
Posts: 914

PostPosted: Mon Oct 03, 2005 12:26 pm    Post subject: Reply with quote

I was afraid that might be the case. What's all involved in the conversion?
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Mon Oct 03, 2005 1:23 pm    Post subject: Reply with quote

It would be a rather long explenation so you might take a look at this post to get a better idea what is involved:

http://www.924board.org/viewtopic.php?t=16712

You can make it as expensive and complicated as you want it to be. It can also be done on the cheap if you are willing to scrounge and utlize used parts. You might also take a look at the Mega Squirt site. It may not be as fancy as the VEMS but it has great support and unlike the VEMS it utilizes totally open code source so it is continually being advanced by anyone who cares to try.

http://www.msefi.com/

Todd
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Racing  



Joined: 27 Apr 2004
Posts: 374

PostPosted: Mon Oct 03, 2005 11:14 pm    Post subject: Reply with quote

A couple a things...
No pun intended for the MS,but the sorry truth is that much like the PC format...it´s grown out of its own motherboard,and most of it should be redesigned.
That´s basically the ground zero for the VEMS.
If you´d taken a VEMS out of its box you´d know what i mean.
The VEMS was set out to be digitally built from the start,and it frankly shows-not only from a physical standpoint.

Only real concern i´ve got..is if the VEMS will deliver on what it´s set out to promise.
THAT is what i´m to find out.

We´re currently for example keepin coms between me and jörgen down to a bare minimum..just to prove the point.

As some of u guys know,i do this crap for a living.
That also means that from time to time i´ve been so pissed at the "black boxes" that i´ve thrown the damn lap top out the window going down the freeway doin 100...cussin my ass of.
For a LOOOOOOOOONG time...i critized the developers of systems for the lack of reliability.
I for one could care LESS if the damn unit can brew coffee on demand.

So..
This time out jörgen et al has used me as "backup".
Sincerly asked me what needs to be adressed
..and IMO...gimme a friggen box that´ll set up coms every time i ask it to.
Gimme a friggin box that takes care of flyback currents especially to the injectors so that the opening times given for them are ACCURATE.
Gimme a box..that´ll work at minus 30 deg celsius.
Gimme a box that´ll take the pounding from being in a car over time.
Gimme a box with resolution high enough to be of any good for an ANAL tuner..
Hell,gimme a box that´ll take a blast from a damn 12ga!

I frankly coulnd´t give less of a rats ass as far as intercooler fans,TCC;s,VANOS,primers and god knows what else...
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Tigger937  



Joined: 11 Apr 2004
Posts: 914

PostPosted: Tue Oct 04, 2005 1:20 am    Post subject: Reply with quote

Racing wrote:
For a LOOOOOOOOONG time...i critized the developers of systems for the lack of reliability.


Typical rush to market problem.

Racing wrote:
Gimme a friggin box that takes care of flyback currents especially to the injectors so that the opening times given for them are ACCURATE.


Free-wheeling diode circuit to handle turn-off for inductive loads?

Racing wrote:
Gimme a box..that´ll work at minus 30 deg celsius.


Don't forget 100% humidity. Equally important if not more so.

Racing wrote:
Gimme a box that´ll take the pounding from being in a car over time.


Vibration testing.

Racing wrote:
Gimme a box with resolution high enough to be of any good for an ANAL tuner..


What kind of resolution are you looking for?

Racing wrote:
Hell,gimme a box that´ll take a blast from a damn 12ga!


Shock testing.


Sounds like what you want is something designed to MIL SPECS. This does NOT come cheap as much additional development/test time is required. There's a reason why hammers and toilet seats cost $600 usd in the military.
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Tue Oct 04, 2005 4:23 am    Post subject: Reply with quote

Reliability?! How could MS not be reliable? It is put together by dolts like me who didn't know wich end of soldering iron was for business until I smelled the burning flesh!

I was actually part of the second group purchase of MS so I have seen it grow considerably over the years. I understand your concerns. From what I have read on the net about other systems reliability, leaves a bit to be desired also.

I am only posting this in defense of MS and not to convince you of anything but to only inform others of some of the advances of MS.

Reliability can only be suggested by the millions of miles in thousands of cars MS has under its belt. Most of these are only street cars and not the stuff you work on so are not put thru the rigors you instill on your cars.

As far as "anal" tuning and flyback problems, these can be traced to resolution. The new MSII has improved this from .01sec to .0001sec! Processor speed is greatly enhanced and capable of contolling huge injectors for decent idle.

I really wish MS had a couple of features the VEMS has including the direct control with a simple LCD and a keyboard. This would be SOOOOO nice!! I hate using the laptop but this is part of the price I pay for being cheap! As I said before I like the idea of the "self learing" feature. Seems kind stupid proof and lord knows I need that

Todd
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Racing  



Joined: 27 Apr 2004
Posts: 374

PostPosted: Tue Oct 04, 2005 4:30 am    Post subject: Reply with quote

Tigger,basically you´re right.
But the point is....
I´ve been around this crap with programable EFIs since the mid 80s when i first got in contact with the then fabled haltech F3.
Since..i´ve dived into more or less every reputable system on the market.
Some better than others,and..again..more often than not misunderstood by the average Joe(read tuner)

Resolution wise,i need a 16 by 16 map to get the resolution i´m after.
Or..really more to the point that WAS what was needed at one time as the interpolarization between map cells really left something to be desired.
Likewise..
When it came to repeatability.
You adjusted an EFI a mere 10 yrs back to be spot on on the dyno...
When you then reached the track and had for example an LM-11(early wideband by Bosch)installed..it was wayyyyyyy out there.
Of course...one first has suspicions as far as relative temps and barometric conditions,but..the honest truth was that the time fram given for injetion pulses to happen left the designers in a state of confusion as far as quality of components.
Just cause any given vendor of circuitry "said" something..didn´t really mean that it was what happend.
Ie;minute variations in circuitry could very well have massive implimentations from a practical standpoint for the engine in case.Leaving you with one serious melt down a la harrisburg.

..and...we´ve come a long way.

Couple a yrs back i decided to put an Haltech E6 to the test for real.
Of course to cater to my own needs in a way,but mainly to get a REAL feel for what my customers were to expect when they installed en aftermarket ECU instead of the OEM one.(read long term street use)
And..i have to say that at that point haltech really had gotten their shit together as that E6H on my then C4 vette with dart heads,cam asf..performed.(Ran a corrected 11.67 directly off the street with simple M&H out back)
To a mileage that really put a smile on my face to boot.(have in mind that around these parts it gets COLD in the winter-for real)

However..
Maping isn´t really for everybody when u as a tuner need to interpret what the engine is tellin you as far as needs.
In that respect we´ve reached further-albeit not far enough-with the intro of contemorary wideband lambda sensors.
Another thing often misunderstood.

Anyways.
Like i wrote above what gets me with the VEMS is the ability not only to have it "learn" itself,but doing so within a LOT of given parameters.
As far as i´ve gathered with the beta unit i´ve got for testing you can really just tell the VEMS what AFR to chase at any given practical load,and the interpolarization between cells seems to be "reasonable" at least.
As i jumped all over jörgen amongst others at the design state they also adressed the issue of flyback currents-albeit in a crude manner.
Couple that,with the ability to interface the WB O2 info with the EGT values picked up all over the place if need be at least gives the average Joe something that actually just might work WITHOUT a second mortage on the house.

But...
As always there´s a but...
As far as i´m concerned there will ALWAYS be a need for the pro tuner.
Reason is simple really.
There´s no way in hell..i´m gonna build a 40k race engine and put that in the hands of a electromechanical device as a WB sensor that puts you back 200 bux tops...and some K series thermo wire.
Just stands to logic.
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Racing  



Joined: 27 Apr 2004
Posts: 374

PostPosted: Tue Oct 04, 2005 4:43 am    Post subject: Reply with quote

Todd.
Don´t get me wrong,cause i aint jumpin on the MS.
I´m jumpin at ALL of them.
Hell,i even got one of the MS1s laying around the house still...thought i´d put it on my mach1 one of these days with a simple adoption of a complete YB off a chebby truck or sumthin.
So..by all means dont get me wrong.

However..when you sit down and study the two different boards side by side..its like comparing Busch grand national with a weekend racer.
No offense,but that´s juse the way it is.
What´s more..
I truly bow to bowling n grippo for what they put out at one time
An AFFORDABLE DYI EFi for the average Joe.
That was a first as far as i´m concerned.

Point is that over the yrs there´s been about as many manufact of EFIs as you have underwear...
To a point where they all reinvented the wheel,and STILL no cigar.

Point in Q.
Got a cust that runs a Mitsu EVO.
Fairly hardcore,dynoed inxs of 500(number 526 comes to mind)
Sports a GEMS box.
Guy seeks me out to remedy a high end miss.
Ign..is an MSD6DIS.
Guess what.
GEMS...won´t let ANYONE in their systems that hasn´t payed GEMSs anual fee...
I was like..WTF?

I´ve seen cars sporting EFIs refuse to start...cause it turned sub zero(celsius).
I´ve seen em melt down every way poss come sunday...
..and frankly..that is NOT ok.
You purchase a prod to have it perform.

Same deal with this internet hysteria..
This week...autronic is THE box to have on the shelf.
Next week its speed pro/fast,to be followed by the next and the next and the next...
The TRUTH...the TRUTH is that they´re made to perform the same task every god damn one of them.
-see my points above.

Cudos..to bowling and grippo,cause if they´ve done ONE thing its to put pressure on those that at one point more or less cashed in on puttin a sub par product on the market.
..and what´s more...
As the MS is something you normaly put together yourself...you know how its built with the stims and god knows what else...
That ALSO means...that when it Fs up...you can repair it yourself.
..or ask one of the as you correctly state THOUSANDS that have done the same thing what might be at fault.

But...it was NEVER intended to be anything but a crude way for the DIYer to FI any engine.
Let´s be frank about that.
..and seing that...the current VEMS is in another league.
No two ways about it.
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