Another megasquirt question

Ed G

Ed G

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Does anyone have a feeling for what megasquirt might do for an original 3.0 CSI engine as far as power increase? Some previous posts indicate the original 3 liter D-jet is almost maxxed out given it's flow capabilities and not worth spending time and money on. My thought process makes me feel it would not be unlike chipping a motronic engine and have some value???
 
It would provide a huge improvement in driveabilty and fuel economy, if not outright torque and horsepower. The problem is that it is not a simple bolt-on affair and requires a custom harness and sensors. But yes, adapting to any modern injection system will yield noticeable performance gains once it is tuned correctly (which is no easy feat, either).

I'm starting on another custom injection system which will run a Delphi ECU with sequential injection and separate coils per cylinder. I've been thinking about building up a few harnesses and sensor kits that would be a bolt-on affair for use with Delphi or Megasquirt. Just don't know if there's a market for it or what people would be willing to pay, but will post up pictures of the progress after the new year.
 
As an example - one area of improvement relating to power would be the spark advance control. The current CS/CSi set up with the distributor relies just on the centrifugal weights and the vacuum advance for this control. Whereas, the MS will allow every load and rpm combination to be unique. It also has settings for spark retard for cold conditions, starting, and hot air intake conditions (after heat soak). Of course, getting all these table positions dialed in is no easy feat, like Andy says.

Aside from maybe a bit more power, the control over warm-up running and various idle conditions is also improved.

Diagnostics using the laptop is nice feature as well. No special BMW tool #xx required.

Have fun,
 
A plug for D-jet...

I'm sure most won't agree but I believe a well tuned D-jet car is pretty nice driving and no fuss. The problem lies in the fact that they've usually been messed with by someone who doesn't understand the system and that combined with a tired engine (can you say low vacuum) makes for some drivability issues. My CSi starts and idles without any fuss and pulls without a stumble right to redline.

200 hp and 200 ft lbs of torque ain't bad for stock out of the gate... I would love to see a dyno on a stock CSi motor with some other engine management system to see the actual difference. I suspect no one has one though since other mods are usually involved to take advantage of the potential of a modern engine management system.

Another thing to consider, I think (hope) that the CSi cars are becoming more valuable and at the top of that category is "original" cars.

Nothing against going the other route and spending the money and time (lots of time) getting it dialed in to start, idle and pull strong no matter where you are in the MAP.

Go D-jet!
 
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Why megasquirt is winning the war....

13 Control unit D-JETRONIC 1 13611355309 ENDED

06 FUEL INJECTION SYSTEM-PRESSURE SENSOR 13631360678 ENDED

10 Temperature sensor air 1 13621353331 $84.44

06 WIRING HARNESS FOR FUEL INJECTION 61121356010 ENDED

08 Intake muffler 1 13721256550 ENDED

01 Distributor 1 02/1972 11/1975 12111268361 $1,472.91

Well known fact that BMW spent the last 20 years destroying all the NOS items they could find in every dealership in the country.
 
okay i'll bite ... i've got a 3.5 conversion (motronic 1.0 - i assume L-jet). what can i read to better understand what is involved in migrating to MS?

unfortunately i'm on the east coast so i can't bring it to you.
cheers

scott

sfdon said:
Why megasquirt is winning the war....

13 Control unit D-JETRONIC 1 13611355309 ENDED

06 FUEL INJECTION SYSTEM-PRESSURE SENSOR 13631360678 ENDED

10 Temperature sensor air 1 13621353331 $84.44

06 WIRING HARNESS FOR FUEL INJECTION 61121356010 ENDED

08 Intake muffler 1 13721256550 ENDED

01 Distributor 1 02/1972 11/1975 12111268361 $1,472.91

Well known fact that BMW spent the last 20 years destroying all the NOS items they could find in every dealership in the country.
Click to expand...
 
The simplest conversion is just a 3.5 motor in a coupe with a fresh Motronic ecu like a "179" unit. Adaptive technology and great idle and so very dependable. Dirt cheap and works great.
Every part is found in junkyards.
Next step is high compression, ported head, hot cam and now you need Megasquirt.

pm me if you have questions.
 
SFDon and others, just wondering if there is a clear benefit to running something like an EDIS ignition with Triple Webers? Is the main benefit to Megasquirt on the ignition side? My car is running a vacuum distributor that is not hooked up. No idea if it has been modded, but others have commented that it should not be running such a distributor.
 
Interesting thread. My observations of MS have been only online, but isn't MS based on an onboard manifold vacuum sensor (which is what D-jet is/does, except the sensor is not onboard)?

And if MS is based mainly on manifold vacuum, other than the age and condion of Djet sensors, how is it/can it be better?

I could admit some benefit if MS system also controls spark advance; I also suppose MS allows one to tune (somewhat more readily, perhaps) to a specific A/F ratio.
 
Engine management systems like megasquirt give you more control in tuning the fuel and timing curves for your engine, and they adjust these settings in real-time based on feedback from engine sensors (like O2, throttle position, MAP, etc.). This dynamic type of control makes your engine run great under all conditions (e.g. altitude, cold start, etc.).

While some would argue that you can achieve the same results with a carbureted setup, computer-based ECUs allow tuning with a keystroke, and closed-loop feedback with real-time sensors. In my humble opinion (and, incidentally, consistent with the manufacturing strategies of all of today's car manufacturers), these systems are much better than carbs.
 
The djet system works great when it works like it should.

Djet uses 13 position TPS - MS uses 100 position TPS.
MS controls fuel,spark, retard, advance, retard under boost. Djet controls fuel
No feedback with djet and MS has feedback and offers automatic tuning.
 
There seems to be many here who would like to leverage the convenience and performance benefits of a modern-day ECU, but not many willing to jump in with both feet - AndyM suggested he may make us up a few systems (I presume with wiring loom, sensors, and a tuned ECU?). He asked if there is interest, but none replied. I would be interested to see what he came up with and personally feel it would be worth at least $2K if properly executed. I am sure such a system could be developed (maybe even at a lower cost if there is economy of scale), but would others here be interested in committing a purchase from AndyM to make such a product?

…I for one would try it.
 
Honolulu said:
Interesting thread. My observations of MS have been only online, but isn't MS based on an onboard manifold vacuum sensor (which is what D-jet is/does, except the sensor is not onboard)?

And if MS is based mainly on manifold vacuum, other than the age and condion of Djet sensors, how is it/can it be better?

I could admit some benefit if MS system also controls spark advance; I also suppose MS allows one to tune (somewhat more readily, perhaps) to a specific A/F ratio.
Click to expand...

Hi,

While speed-density systems aren't quite as accurate as mass flow systems, there is a lot to be said for MegaSquirt. For one thing, the D-Jet ECU does not have a microprocessor at all; everything is done by timing loops in hardware. In fact, there isn't a single IC in the whole thing (germanium transistors!). Here's a very informative link: http://members.rennlist.com/pbanders/ecu.htm

With a microcontroller come the obvious advantages- accurate and stable timing, tunability, added refinments (such as varying the injection timing with RPM, bank firing for cold starting, fuel cutoff).

If you bolt on the 60-2 crank wheel off a Motronic 1.3 M30, you can now get precise timing for ignition as well.

Regards.
 
I agree

I feel as though I am almost to "curator" status for d-jet. The ability to read and adjust parameters on the fly via the lap top, real time, is too cool to ignore. The ability to preserve and run the "dinosaur" has its points as well, from the historical stand point. My own fires after a micro second on the starter. Raped ape from there. No issues. But that is what is cool about this hobby, a never ending learning curve. To have a "concourse" quality car would take all the fun out of it for me. The interaction of the members and not to be disrespectful of T. Edison, but I love it that this group is all about "10% perspiration and 90% contemplation"
E911 said:
I'm sure most won't agree but I believe a well tuned D-jet car is pretty nice driving and no fuss. The problem lies in the fact that they've usually been messed with by someone who doesn't understand the system and that combined with a tired engine (can you say low vacuum) makes for some drivability issues. My CSi starts and idles without any fuss and pulls without a stumble right to redline.

200 hp and 200 ft lbs of torque ain't bad for stock out of the gate... I would love to see a dyno on a stock CSi motor with some other engine management system to see the actual difference. I suspect no one has one though since other mods are usually involved to take advantage of the potential of a modern engine management system.

Another thing to consider, I think (hope) that the CSi cars are becoming more valuable and at the top of that category is "original" cars.

Nothing against going the other route and spending the money and time (lots of time) getting it dialed in to start, idle and pull strong no matter where you are in the MAP.

Go D-jet!
Click to expand...
 
pamp said:
Who is AndyM? Since I have interest on both sides and all sides of EFI.
Click to expand...

That would be me. I've been running a GM-based EFI on my 3.5 for the last five years or so and I have a tried and true combination of sensors that will work with just about any aftermarket ECU. Right now I have a one-off, hand-built custom harness (by me) that mimics the stock D-Jet stuff. At first blush, you don't even notice that there's anything different. The plan is to use that as a prototype for a short run of harnesses that can be adapted for GM stuff or Megasquirt (which uses mostly GM stuff anyway).

My car is in disassembly mode right now, but the motor and harness will be on the stand shortly and I'll post up more details. I'm contemplating Ver. 2.0 that will use a Delphi LS1 based ECU with a crank trigger and cam sensor to get sequential injection and separate coils on each cylinder. That may be a lot of work for a little gain, so it may be get tabled, but we'll see. I'll keep you guys posted.
 
Efi

Thanks for the introduction. I for one would be very interested.....If you were to assemble harnesses and provide a list of items needed....part numbers, etc. That would be a huge plus for those of us "sitting on the fence" or "live on an island" as it were. You have a market for sure. BTW.....who are these guys?
http://www.ebay.com/itm/BMW-E23-E24...ies&hash=item2a09431e3c&vxp=mtr#ht_777wt_1141

I guess "plug and play" are the key words here.
 
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