Has anyone tried a VEMS ecu?

I’d never hear of them before last week, when a friend of a friend offered some help the electronics for my v12 conversion project.

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

I went to the web site and got very confused (it was a bit hard for me to find stuff), but after a few emails the ECU they’re making looks pretty good to me and it’s only about $700 with the relevant options.

It appears to do al lot of stuff:
Up to 20 high power outputs that can be set to anything.

For a v8 it could be 8 fuel injectors for (sequential injection), 8 ignition for COP and because the output are high power here is no additional MSD box or ignition modules to buy saving hundreds of dollars. Then 4 outputs left over for whatever.

For my V12 I’d take 12 for fuel injectors, 6 for the ignition which would be either waste-spark coils or possibly pair the COP coils- they are getting back to me on the pairing, it might be too much current for the driver, with 2 left over.

It will also run 1 or 2 distributors instead of COP or waste-spark, which would free up the other channels for whatever.

I will use the 2 left over high power outputs to run the heaters on 2 wideband O2 sensors, which it has inputs to read and run closed loop from.

It’s also got 6 low power outputs to run thing like a tach (configurable so it will get the rpm right on the 308 4 cylinder tach even though the engine is a 12), fuel pump relay, radiator relay, ect.

Then a dedicated 4 wires for an idle air control motor – IAC, which can be used as 4 more low power output if you don’t need the IAC

It’s got a knock sensor available, exhaust gas temp It run 16x14 user defined rpm and load points in the fuel and ignition maps.

Here’s cool feature. It’s got an LCD screen option so you can see what’s going on, then plug in a standard key board and do tuning tweaks with no computer needed. That let’s you can just leave a key board in the car while your doing the final cold start tweaks and stuff that can take while to get right and not worry about your laptop getting stolen.

I can’t find anything wrong with this ECU and I think I’m going to go ahead and try one. It seems like such a good deal I though I’d share as well as see if any you has tried you yet.

 

That's agood unit. I've never owned one, but know several who do/have and are happy.

The Haltech E11 and Motec m800 also are good, the motec inparticular and would work great. But, they are all a LOT more money to buy and install. The haltech and electromotive run about $2500-$3000 with the coils and ignition modules, the motec closer to $5000 (with the v12 and O2 sensor options).

The VEMS is $700 plus $200 for coils. That's a big difference and it appears to do all the same stuff. It's very tempting.....

 

I don't know...I never asked that. I'll shoot them an email.

 

That's what I'm thinking. The Jason from VEMS (the freind of a freind) has offered to spec everything and come down and help get it installed and running.....it seems like a deal too good to pass up.

I'm not sure about the robustness...clearly they do not have bosch type test facilities. They do seem to know electronics though.

The megasquirt units are only $200 as a kit or $400 asembled, so that telsl you what the parts are worth in an ECU. I think aftermarket ECUs have been about $2000-$3000 since the early 1990s anyway....when the price on everything else electronic has come down by a factor 10 while the performance when up by a factor of 1000. It only makes sense that you can build an ECU for not a lot of money.

IMO the Megasquirt guys are electronics guys not car guys and so focused on cost they really don't listen to the car guys they miss the mark badly in a lot of areas. The function is quite limited and you end up with a hodge-podge of boxes and patches before you have a working system.....plug and play it aint.

The VEMS guys also seem to be electronics guys, but have done a good job of getting the right stuff in the box. Appearently the 16x14 maps are new for example, and the feeling I got was they feel it's more marketing than function becasue 8x8 is just fine and the 12x12 was already over-kill.....but they did put the 16x14 maps in and I wouldn't even consider it without them. They did lift the Megatune tuning software because its pretty good and very flexable.

 

No on-board data logging, but it's on the to do list appearently. they have it set-up to log to windows 5.0 or higher PDA and are working on a SD card.

 

Motec charges almost as much for the 12 cyl enable code as a whole VEMS costs. The wide band O2 option cost more than the whole VEMS unit. The data log option cost $300 I think. Then is needs an ignition expander for $300 and 6 igniters for the coils for another $600. The Motec will cost about $5k I think and that doesn't make very good sense for me. I had one here I was going to run with the supercharged engine becasue I needed some of features it had, but that's not the case with this engine. I'm not very familiar with the Autronic.

I think my second choice would be a haltech E11 for $1500. It would mean I have to run distributors, but that's fine.

I'm most likely going to give the VEMS a try because it's WAY cheaper than any other option and appears to have all the features I actually need. The complaints on the efi forum seem to be that the documentation needs help and support is hard to get but in this case both are non-issues because Jason works with a college buddy of mine in his day job, so I know where to find him. That and he seems quite interested in my whole v12 build/conversion project and wants to help so the support will be there and with good support the documentation is a non-issue.

 

Take a look at the motec software, it's very similar in the number of settings it wants. As soon as they say "use any sensor" or "works with most factory triggers" you know you're in for a rough ride setting it up. That's were good documentation and support come in. I think a system like the electromotive is much more plug and play because they require you to use their stuff and they can pre-set eveything for you.

I got an email from Jason yesterday and he suggested running the injectors in 6 pairs of 2.... looking at the software I think I see why...it only lets you configure for 8 injectors. I think that would be fine for this engine since I'm not going to be running monster injectors.

 

Well I know nothing about programming (writing code) so I've got the ignorance is bliss thing going on. I’ll get one and you can help me reconfigure everything

 

i haven't done any programing in..oh almost 20 years guess.

There should be no need to do any with this ECU. The firmware is closed anyway so the only coding that could be done is to the interface software...and without firmware changes only trivial stuff could be done even to that.

I don't know of any engine simulation software, I guess that's one of the things you develope when you are trying to design an ecu.

 

Nothing really. I guess the firmware was open in the 1st generation or was open, but not anymore. I think they discovered exactly what Paul was saying....the "help" is as likely to bugger it up and fix it.

These days the best I can tell, they understand the need for closed software and selling through dealers....it just doesn't work any other way.

 

no, that's what the term "closed" means. It's a small company so I'd guess that if you had a good reason you might be able to get hold of it, if it was a good reason.

The VEMS unit does not do everything and never will. Their goal is to privide an inexpensive ECU that will do the things 90-95% of people need...the last 5-10% adds a lot of cost to the unit with no return for most people. I think it's a good idea. This ECU would not have worked real well on my high boost QV engine, but it seems ideal for the NA engine I'm building....and will save me enough money to pay for the whole engine rebuild compared to a motec.