40 replies to this topic

[Canuck]

One of the things I like best about this forum is the cross-section of people. Dimwits (that's me), OE engineers, racing professionals (and not like dirt-track oval for money professional, but 8 and 9 figure budgets kind of racing) and a plethora of international gearheads/hotrodders with an equally broad spectrum of experience. This section of this lone forum has exposed me to more knowledge than I ever thought I'd find online. I love this place.

On another forum, a discussion peaked my curiosity about "chipping" stock ECUs for modified engines. Of course chipping is already outdated and now things, as I understand it, are flashed. New vehicles are so thoroughly integrated that you couldn't possibly install a "consumer" stand-alone EFI system into your modified M3 with it's SMG transmission. I'm a fan of MegaSquirt but then my daily driver is 21 years old - I'm not exactly drowning in new car technology. Going to a stand-alone system like M/S or Electromotive's Tec3 or any of the plethora of mainstream systems is pretty much a no-brainer if a guy wants to take an old EFI car and modify it beyond the stock ECU's adaptive abilities. 3 sentences in and I'm already drifting away from my original (as yet unasked) question.

While doing some reading about chip tuning, I came across a Bosch-dedicated site wherein the author claims to have "found" in excess of 200 different maps in a BMW 3-series ECU (or DME if you prefer). Yet somewhere else, the author claimed that Bosch was willing to provide you with the tell-all book for their ECU but at a hefty $100k tag. I have to assume that some ECU code could be deciphered through trial & error combined with experience but if there really are even 10s, much less hundreds of maps in a modern ECU, you'd need that book to make any substantial tuning changes. Seems awfully pricey but then maybe I underestimate the value of the ECU tuning market.

What about high-end stand-alone units like the Tag/McLaren units (or whatever they're branded now)? Are they more capable than their "consumer" brethren in a way that makes sense to utilize them in a street-going hotrod? Do OEM ECUs really have hundreds of data tables stuffed into them?

What's the real deal on ECU tuning?

[gruntguru]

One of the things I like best about this forum is the cross-section of people. Dimwits (that's me), OE engineers, racing professionals (and not like dirt-track oval for money professional, but 8 and 9 figure budgets kind of racing) and a plethora of international gearheads/hotrodders with an equally broad spectrum of experience. This section of this lone forum has exposed me to more knowledge than I ever thought I'd find online. I love this place.

On another forum, a discussion peaked my curiosity about "chipping" stock ECUs for modified engines. Of course chipping is already outdated and now things, as I understand it, are flashed. New vehicles are so thoroughly integrated that you couldn't possibly install a "consumer" stand-alone EFI system into your modified M3 with it's SMG transmission. I'm a fan of MegaSquirt but then my daily driver is 21 years old - I'm not exactly drowning in new car technology. Going to a stand-alone system like M/S or Electromotive's Tec3 or any of the plethora of mainstream systems is pretty much a no-brainer if a guy wants to take an old EFI car and modify it beyond the stock ECU's adaptive abilities. 3 sentences in and I'm already drifting away from my original (as yet unasked) question.

While doing some reading about chip tuning, I came across a Bosch-dedicated site wherein the author claims to have "found" in excess of 200 different maps in a BMW 3-series ECU (or DME if you prefer). Yet somewhere else, the author claimed that Bosch was willing to provide you with the tell-all book for their ECU but at a hefty $100k tag. I have to assume that some ECU code could be deciphered through trial & error combined with experience but if there really are even 10s, much less hundreds of maps in a modern ECU, you'd need that book to make any substantial tuning changes. Seems awfully pricey but then maybe I underestimate the value of the ECU tuning market.

What about high-end stand-alone units like the Tag/McLaren units (or whatever they're branded now)? Are they more capable than their "consumer" brethren in a way that makes sense to utilize them in a street-going hotrod? Do OEM ECUs really have hundreds of data tables stuffed into them?

What's the real deal on ECU tuning?

The figure of 200 maps is feasible although I can't confirm it specifically.

Off-the shelf chip installation is a waste of time unless the engine is turbocharged, in which case there is a parameter that can be usefully altered (boost pressure). Other valid uses would be a chip to suit a different fuel or a chip to match a specific modification package.

Custom re-mapping of your ECU on a dyno can see gains (may not too, depends on where your engine sits on the spectrum of manufacturing tolerances.) Of course if you have modified the engine custom mapping will definitely see benefits.

If the engine is heavily modified the best solution is an aftermarket programmable ECU eg Motec. The vast majority of cars can be retrofitted. In some cases, sophisticated vehicle control systems will still need to be handled by the original ECU.

What about high-end stand-alone units like the Tag/McLaren units (or whatever they're branded now)? Are they more capable than their "consumer" brethren in a way that makes sense to utilize them in a street-going hotrod? NO.

[Greg Locock]

An EEPROM with which I am working (not engines) has 8 slots for calibrations. If we use them now they cost nothing. If we leave them empty the production chip won't have them. I rather imagine we'll go into production with two useful cals, and 6 placeholders for later programs. I rather doubt a chip would ship with 200 useful calibrations - in fact they may not even be for that engine.

Also of course hardly any of them will be concerned with WOT, most will be drivability/emissions tunes.

[gruntguru]

An EEPROM with which I am working (not engines) has 8 slots for calibrations. If we use them now they cost nothing. If we leave them empty the production chip won't have them. I rather imagine we'll go into production with two useful cals, and 6 placeholders for later programs. I rather doubt a chip would ship with 200 useful calibrations - in fact they may not even be for that engine.

Also of course hardly any of them will be concerned with WOT, most will be drivability/emissions tunes.

I didn't read the OP as 200 "Tunes" but 200 "maps" which could include mapping of all sorts of things from fuel and ignition to valve timing, transmission etc

Edited by gruntguru, 11 June 2009 - 09:39.

[McGuire]

First, congratulations on the baby boy.

As you say, stock ECU vs. standalone/aftermarket depends on what you have and what you intend to do with it. If the original ECU utilizes a pullout PROM/EPROM//EEPROM for calibration, it's probably too old and limited to take very far. For most street-type applications, if there is a software editor available for the OE ECU you are good to go. Big turbos, more + bigger injectors etc. may require an aftermarket box. Piggybacks on stock ECUs are generally a pain and not terribly elegant, though lots of people have used them effectively. The MegaSquirt is the classic low-buck approach: great if you are the low-buck type and enjoy spending time rather than $$$ and eschew the elaborate. Looks crude to pros, works good. AEM is nice for its compatibility with OE wiring and connectors etc. Motec is popular in sportsman road racing. Electomotive is clever if a little irritating. FAST and BigStuff3 work well too. To me, much of what you read on the web about the usability of various systems is actually more about the particular poster. He might be ripping on Brand X where he would be perfectly happy with Brand Y for reasons that have nothing to do with Brand X. Brand Y is simply more suited to his methodology and application.

I don't know what the guy is buying from Bosch for $100K. OE calibration works at a far greater level of detail than aftermarket tuning. The active documentation for a single application runs into thousands of pages and is extremely proprietary. In the aftermarket they are essentially working the tip of the iceberg, on a few dozen overlying parameters rather than the hundreds or thousands underlying them. OEs and their suppliers generally employ the ETAS Inca interface, which interprets Motorola S hex code as ASAM2 format so humans can read it. Too expensive for the home tuner or even most hot rod shops but required for OE-quality calibrations. The aftermarket ECU is more simple and transparent for the driveway mechanic, especially on an older car where there are few or no vehicle integration issues.

[Canuck]

Yeah, that was 200 maps, not tunes. That's astonishing but then I suppose depending on what that unit is looking after (engine only or engine/trans/chassis/etc), it begins to make sense.

MoTec was the name on the tip of my tongue last night but I couldn't remember it. I'd started the process to sign on as dealer back when I had the motorcycle dealership but got put off when, after getting the AUS pricing was told that I had to buy through the US distributor (which meant paying duty 2x on top of a higher cost and shittier exchange rate). I digress...I think McGuire manage to understand what I was asking. In essence, aftermarket systems have nothing on OEM units at all - the level of sophistication in the engine tuning alone is, if I understand correctly, light years more thorough and complete. MegaSquirt appeals to me precisely because I have more spare time than spare money (though that's just taken a hit too - thanks McGuire).

So, what does a MoTec unit have that an M/S unit doesn't (if we assume the M/S is assembled with some skill)? What about a Tag vs. a MoTec? How are aftermarket tuners, specifically with late-model products and their involved ECUs, managing to crack the tunes even a little? With 200+ tables, how do you even begin to know where to start? How do guys like Superchips with their handheld units get even as far as they do?

I'm curious - perhaps it's not a simple delineation but where does Bosch stop and an OE start? Who does the actual mapping and programming? How much does Bosch charge an OEM to supply a new ECU system?

[Greg Locock]

Yeah, that was 200 maps, not tunes. That's astonishing but then I suppose depending on what that unit is looking after (engine only or engine/trans/chassis/etc), it begins to make sense.

trans shift, HVAC, fuel, spark are the big tables I know about (I've worked on the HVAC cooling stuff for a few weeks, it is interesting), but there are also modifiers, which might be tables in their own right, and once you include different vehicle masses/trans/engines I can see that 200 distinct tables might be possible. There's always some cost reduction team claiming it is better to have unique EECs for each variant, and another saying that it is better to have a more flexible EEC that can figure out the appropriate variant and run the relevant cal.

[ray b]

the GM cpu 1227730 is used in 4 cyl and v6 and v8 chevy motors 87 to 92
and has been hacked to run the caddy DOHC northstar V8 along with a few other odd ball motors
http://northstar.7p.com/

sometimes a stock hacked cpu is the cheaper eazyer way to go even if it is not stock to your motor

[ray b]

I donot know about BMW's
but volvo bosch units have been hacked for the b-230's esp turbo with high boost

and some people have had some luck with running a trans controler for el-trick auto trans cars
with a different CPU ecu DME what ever you want to call it to run the motor

[gruntguru]

In essence, aftermarket systems have nothing on OEM units at all - the level of sophistication in the engine tuning alone is, if I understand correctly, light years more thorough and complete.

So, what does a MoTec unit have that an M/S unit doesn't (if we assume the M/S is assembled with some skill)? What about a Tag vs. a MoTec?

I'm curious - perhaps it's not a simple delineation but where does Bosch stop and an OE start? Who does the actual mapping and programming? How much does Bosch charge an OEM to supply a new ECU system?

What a Motec unit has vs an OE unit is ease of tuning. It is easy to dismiss the Motec as having far fewer mapping sites for example, but more sites means more time spent tuning. On top of that the Motec has a lot of flexibility in the number of sites used (don't know what the limit is but it is pretty high) and variable site density so that areas that need to be mapped in more detail can have additional sites - so probably similar density to OE if you have the time to tune it.

Can't comment on M'S or Tag.

[Canuck]

Ahhh....same ECU, different vehicles, all programmed - hadn't thought of that. Well that starts to make good sense then - it may be that the BMW DME in question actually runs a multitiude of different vehicles and thus the hundreds of maps starts to look more manageable. I had a look at the Northstar page and the authors OEM vs. Stand-alone page (I too had nothing but disaster with the first-gen Holley Projection, but I attributed that to being a poor product, not an industry-wide blunder. The final deal breaker, apart from it not running well was the propensity for it to hold the injectors open when the engine wasn't running but the key was on). The GM ECU they're referring to also runs a handful of different vehicles and is apparently fairly well cracked, hence the preference for it in the aftermarket.

I would guess a unit like the MoTec to be more reliable than something like the M/S, especially given it's 10x price tag (depending on options). I was back skimming their site yesterday and couldn't help but notice that there were a lot of optional things like logging and WB02 use, things that are standard with an M/S unit if you want. On the flip side I suspect, like Grunt said, the M/S won't have the density available that the MoTec has.

Okay...so if you were running a non-stock engine configuration, perhaps in a non-standard application would you tend towards a flashed / chipped ECU or a stand-alone unit? And what about late-model ECUs - can they be as extensibly tuned as the old removable prom type with simple hobbyist tools?

Edited by Canuck, 12 June 2009 - 16:47.

[gruntguru]

Okay...so if you were running a non-stock engine configuration, perhaps in a non-standard application would you tend towards a flashed / chipped ECU or a stand-alone unit? And what about late-model ECUs - can they be as extensibly tuned as the old removable prom type with simple hobbyist tools?

The best results will only be obtained by re-mapping fuel and ignition on a dyno. If you have access to a competent tuning shop with a crack for your OE computer - good. If not, a Motec or equivalent will get as good or better results, and most good dyno shops will be familiar with the process.

When I say "better results" it is because it is unlikely a "crack" of the OE computer will have all of the Motec features such as
- full sequential injection
- mapping of injector timing
- individual cylinder fuel trim
- individual cylinder ignition timing trim
- traction control
- launch control
- anti-lag (turbo)
- RPM limit
- Gearchange cut
- wideband lambda interface
- additional injectors (mapped separately)
- ability to change between throttle/MAP/AFM mapping or even combinations of these for turbo installations
- change ignition types eg multi-coil, waste spark, distributor.
To mention just a few.

Edited by gruntguru, 13 June 2009 - 20:27.

[Canuck]

[bobqzzi]

I have seen an aftermarket tuner working with a Bosch ME7 ECU- I think 200 may be a very conservative number when it comes to maps. To get the info to even start tuning these ECUs he did have to buy some of the info (including checksums) which IIRC was something like 10K per ecu application. It is many times more sophisticated than the typical consumer level ecu like a Motec. Earlier Bosch stuff is not so complicated and you can find editing software for it.

As for aftermarket vs OEM- it really is a matter of convenience- if you haev a well know combination for which there is a good tune availble, I would stay with the OEM ECU. If you want to be able to test and tune youself, then an aftermarket system is the way to go.

I do not recommend Electromotive Unit at all- primitive, inflexible, and the software is dreadful. MS can work okay, but it is a bit of a trial deciphering all the jargon, and searching through wikis trying to figure out how it works. If I remember right, you have a VW. If so, you probably want to talk to this guy http://www.lugtronic.com/ who has adapted MS into a plug and play package for VAG cars.

There are a number of systems that are quite a bit cheaper than the Motec made by companies that are easier to deal with. They had a state of the art system for a long time, and charged accordingly. Now it is just one among many, but they still charge a premium price. None will be as sophisticated as a late model ECU, but then again you can actually adjust the parameters b y following the instructions (although I have never seen any ecu with complete documentation; each has its own foibles)

[Greg Locock]

One of the nice things about Motec is their graphing software, it seems very powerful and intuitive. If it wasn't locked to their data format I'd use it for other stuff.

[mariner]

I am definitely NOT into all this ECU mapping stuff but may I ask the more expert a question?

Can you fully map a tunable ECU purely on a fixed dyno or does it require "on road mapping " to get it to work well? I am not talking about pure race applications but for vehicles that have to be used on the road.

I ask this because the guy who built my V 8 is a Motec agent in the UK and fits their ECU to a lot of engines. He mentioned once that one of his more scary moments was sitting in the passenger seat of an Ultima kit car witha high output chevy small block while the owner drove it on the road and he had to use a laptop to fine tune the Motec mapping. As he has a full dyno facility with acceleration loading I assume that they felt on road tuning was still eeded for drivabilty.

Do OEM mfrs do final tuning on the road or not?

[McGuire]

Do OEM mfrs do final tuning on the road or not?

Yes. The bulk of it on the proving grounds, but some public roads too -- including the traditional field testing in heat, cold, and altitude environments. Obviously, calibration will be a key part of all that. For example, one OE has a field office in BFE, Ontario several hundred miles north of Sudbury. (The other two are also around there.) It's built next to the airport so they can use the runways for testing when the roads are impassable. You fly in there via something called Bearskin Airlines, which is pretty much what it sounds like.

On cars with air/air charge coolers, the fuel and spark calibrations will have to be performed at speed on the road. Unless your your chassis dyno is installed in a full-scale WT.

Canuck asked earlier who does the calibrating. A calibration group may consist of people from the box maker, the OE, and (increasingly) contract people, working under a manager who is OE. As the technology advances less manpower is required. That said, production calibration is many, many times more involved than in the aftermarket. An aftermarket "calibration" on an OE box is typically 97 percent stock, original calibration with 3 percent tweaking... often performed by blocking or shutting off or shaving down OE features, for example cat protection or knock control.

I think we need to distinguish calibrations, maps, and tables, which are different entities. An OE CPU generally has only one calibration in it at a time, though it may be stored in more than one format for backup and access. This one calibration is capable of reading from or writing to any number of maps and tables to execute fuel and spark delivery and whatever else it has been tasked with. The calibration can also operate the engine in a number of different ways -- open and closed loop, failsafes and limp-homes, diagnostic routines, etc. A racing EFI system is fairly simple in comparison. The first production EFI systems, including the first several generations of Bosch Motronic, used analog CPUs. Looking at them today, it's like there's nothing there. At the time it seemed like rocket science.

An OE box also keeps its own running calibrations if you will, adaptive or learned functions including fuel trims, virtual fuel identifier, O2S and cat degradation, shift management, etc. If your late-model production car is running funny, try unplugging the CPU for oh, 30 minutes. This is called a hard reset and will put the CPU back on its virgin calibration. Not everything a CPU learns is good. However, don't do this if the MIL (malfunction indicator lamp) is coming on as it will erase any diagnostic trouble codes and failure records.

[mariner]

Completely off topic but Timmins Ontario is famous for two things I beleive.

One , of course , is Shania Twain : the other is it's use as a cold weather OEM test centre. Apparently the local houswives get work as test drivers just going through the cold soak/start up cycles. According to one story they take some candles and matches just in case of a breakdown as two candles alight inside a car can make a difference in surviving hypothermia.


I guess that the housewives view of the various mfrs reliabity might be worth knowing.

[Canuck]

Awesome - thanks for all the feedback. I figured there must be some legitimate means of tackling an newer ECU, and the $10k tag makes considerably more sense than the $100k I'd heard elsewhere. That's a number a guy can build a business model around.

I did at one time have a VW with the 1.8 4-valve 4-cylinder - an engine I was most impressed with. You might remember it's fate from my thread about the broken cam belt. Today I have a collection of 5-series BMWs (2 E12s and 2 E28s), much to my wife's dismany. I quite enjoy the cars but suffer from can't leave it aloneitis and this could use a little more oomph syndrome so have been looking at myriad means to coax some more output from the M30. Ultimately the bang-fer-buck calculation leads to forced induction and the inclusion of some sort of proper fueling/spark control to go with it. Of course, recent familial developments have push that project a little further back (three college funds? ) but one of these days I'll get the time, space and money to do it.

M/S is the most likely scenario for cost, but I haven't yet looked at the Adaptronic unit. SDS is made within 10 minutes of where I live but it seems to me it got stroked off the list for lack of something I thought significant (but maybe I'm just being picky).

The bulk of tuning I see on the M/S forums is road-based with a lot of logging and tweaking with a final tune done on the dyno. I've put thousands of kilometers on the chassis dyno tuning carbureted motorcycles but never a car. Going from a dyno-equipped facility into a place without (but with nice straight roads and very lax enforcement) was good for tuning skills and that level of awareness but I'm not sure I'd want to be in an Ultima doing it (man do I love that car).

[Canuck]

Ford used to come to my home town with a fleet of test vehicles and pre-prod units for cold weather testing, and Porsche used to bring through a small parade of vehicles they would tour through the NWT. The Ford engineers were often from the UK and Germany and for reasons I have yet to fully understand, my non-gearhead parents managed to befriend them and have them over for dinner every time they were in town. This sadly was well after I was out of the house.

According to some of the reading I was doing, earlier Bosch units for Porsche would have a multitiude of different tunes on board that were selected via a jumper wire. They included NA, Euro versions for the same cars at the very least.

[bobqzzi]

My one trip through Death Valley was made much more exciting by the observation of many diffrent makes of cars blasting around with laptops attached to the dashboards. There were a number of BMWs, several Ford Excursions (blasting up the foothills at full chat in 100 degree temperatures) and at least 3 Mini-Coopers prior to their US release. I stopped to talk to the Mini-Cooper guys and they were quite nice.

[kikiturbo2]

this issue of standalone vs. OE ECU has been a hot topic lately in the world of mitsubishi Evolution tuning..

While tuners have been quick to install various standalone units before (from plug and play ones to universal models that required specific harnesses..) we are currently seeing a switch back to OE ecu for applications of up to 500- 600 bhp..
The major influence on this has been the availability of free software which enabled reflashing of the ECU and the great number of people cracking the OE maps and software..

so now the situation is that not only are we able to change the standard maps, but also load modified software in the OE ECU which gives us the additional functions like valet mode, multiple maps, etc... The latest development is the possibility of going to MAP based ECU control instead of MAF based, which has been the main reason for going to standalone ECU... and also the new live mapping option...

Using the OE ecu is attractive because it is cheap, and you keep the very good OE knock control which comes adjusted for the block/combustion chamber allready, and all the temp and pressure trims... so I'd say that you can use the OEM ECU for quite a while before needing to change to somethin special..

[J. Edlund]

Yeah, that was 200 maps, not tunes. That's astonishing but then I suppose depending on what that unit is looking after (engine only or engine/trans/chassis/etc), it begins to make sense.

MoTec was the name on the tip of my tongue last night but I couldn't remember it. I'd started the process to sign on as dealer back when I had the motorcycle dealership but got put off when, after getting the AUS pricing was told that I had to buy through the US distributor (which meant paying duty 2x on top of a higher cost and shittier exchange rate). I digress...I think McGuire manage to understand what I was asking. In essence, aftermarket systems have nothing on OEM units at all - the level of sophistication in the engine tuning alone is, if I understand correctly, light years more thorough and complete. MegaSquirt appeals to me precisely because I have more spare time than spare money (though that's just taken a hit too - thanks McGuire).

So, what does a MoTec unit have that an M/S unit doesn't (if we assume the M/S is assembled with some skill)? What about a Tag vs. a MoTec? How are aftermarket tuners, specifically with late-model products and their involved ECUs, managing to crack the tunes even a little? With 200+ tables, how do you even begin to know where to start? How do guys like Superchips with their handheld units get even as far as they do?

I'm curious - perhaps it's not a simple delineation but where does Bosch stop and an OE start? Who does the actual mapping and programming? How much does Bosch charge an OEM to supply a new ECU system?

200 maps is probably a bit on the conservative side, but it also depends on what you mean by 'maps'. An OEM ECU contain several tables with different number of values. For instance, one ECU (engine only) can contain 11 tables with 288 values (16x18), 13 tables with 256 values, 1 table with 168 values, 3 with 144 values and so on all the way down to tables with only one value. In total you have hundreds of tables in the ECU. It is the 'big' tables like the 16x18 ones that handles normal ignition, but there are smaller tables for temperature correction of ignition angle, startup ignition angle and such. There are a lot of tables that handles everything from translating the gas pedal position to torque demand, to tables used to look up exhaust temperature (used to control lambda sensor heating for instance) or the amount of torque the engine must request for maintaining car speed with the cruise control activated.

Modern OEM ECU's usually have a torque based structure; that is' they are based on torque requests which then are used to control the airflow into the engine by means of an electronic throttle and boost pressure in charged engines. High end aftermarket ECU's often use the same approach, such as the units from Bosch Motorsport. In the case of Bosch, I think their entry level units are actually based on the same OEM hardware, but with a different 'firmware' which allows the user to set the variables they wish with the included software.

McLaren (TAG) units are very different from the units from Motec and similar. With older high end McLaren units McLaren supplied the unit with an application specific 'firmware'. Later versions tend to use Matlab/Simulink autocoding where the user makes their own application code. This is an easy and fast way for the user to develope the functions they need from the ECU. The ECU itself is very powerful in terms of computing power (it's based on PowerPC processors), and they make use of 'companion units'. Companion units are connected to the ECU, or more correctly powertrain control unit, through a CAN bus and they can have different functions from powering the fuel injectors to real time analysis of cylinder pressure and ionization current data.

[kikiturbo2]

this reminds me of an article in racecar engineering where a Pectel chassis control unit from a ford focus WRC was used to run a privately owned Peugeot F1 engine..

[J. Edlund]

this reminds me of an article in racecar engineering where a Pectel chassis control unit from a ford focus WRC was used to run a privately owned Peugeot F1 engine..

Those Peugeot engines originally used TAG control units I believe, the situation was the same with the Asiatech branded version of that engine. But the TAG unit with electrohydraulic throttles was probably not a cost effective solution for a private user.

[kikiturbo2]

IIRC, the problem was that Peugeot wouldn't release the ECU's for private use..

so a Pectel unit was adapted.. the biggest problem being the drivers and valves for the pneumatic valvetrain..

[Canuck]

Sorry, yes - when I say map, I'm thinking of a 2 or 3 dimensional table. I'm starting to understand a little better - still seems to be an enormous number of values when thinking of 11 tables x 288 values per table. Would all 11 tables be handling the same basic function (ignition), but under different operating parameters?

WRT M/S vs. Motec vs. OEM vs. Bosch Motorsport etc, it would seem that not only do you get increasing level of functional complexity as you go up the chain, but each requires a larger skillset to utilize.

[McGuire]

so a Pectel unit was adapted.. the biggest problem being the drivers and valves for the pneumatic valvetrain..

Why would that be any problem?

[kikiturbo2]

Why would that be any problem?

I finally dug up the article, if anyone is interested, I'll scan it..

it is a GEMS chasis control unit, not pectel..

I was mistaken, it wasn't directly related to pneumatic valves.. the problem was that the engine is 10 cylinder and 17000 RPM... which was too much for commercially available systems at that time.. also they needed gearbox and clutch control and datalogging all in one.
also they did not use moog valves due to cost. etc..
I found it very interesting that you could use a generic unit and just program it another way... When I was in college I developed a standalone ECU that was based on a slow microcontroller and since I wanted high accuracy and speed, I had to develop a specific "unit" to handle all the outputs individually.. it was pure hard wired logic..

[J. Edlund]

Sorry, yes - when I say map, I'm thinking of a 2 or 3 dimensional table. I'm starting to understand a little better - still seems to be an enormous number of values when thinking of 11 tables x 288 values per table. Would all 11 tables be handling the same basic function (ignition), but under different operating parameters?

WRT M/S vs. Motec vs. OEM vs. Bosch Motorsport etc, it would seem that not only do you get increasing level of functional complexity as you go up the chain, but each requires a larger skillset to utilize.

There are a few ignition maps in an ECU. Typically you have startup ignition (used before the engine has reached idle speed), idle ignition (used for idle) and normal ignition (used for all other times). The normal ignition map is usually based on engine speed vs. airmass/combustion in the case of ECU's with torque structure. Then there are correction tables for coolant temperature and air intake temperature, and there is also a correction table used when the catalyst is cold.

[kikiturbo2]

on the mitsubishi Evo ECU, we have 2 15x20 cell fuel maps (hi and low octane) , 6 ignition maps (2 sets of 3 hi and low octane maps, again 15x20), 3 ignition trim maps accorting to engine temp, cam timing map, and a whole bunch of small trim maps (enrichment, cranking enrichment etc etc..)
all in all it is a 512 KB "map" but that includes the software..

[Canuck]

Back from the dead I know...went from two to three kids when I initially wrote this thread - I had no idea how little time I would have not to mention a new job and a move too. Anyway...

I find myself with some of those OE vs. a/m questions that had been answered here already. I was thinking that if I had the OE maps from my 20 year old BMW/Bosche DME, it would make setting up an aftermarket ecu simpler (an ECU being the first step towards forced induction - one problem at a time). Eventually I ended up on a site pimping software to extract all 75 tables from the old Porsche 944 DME. The little video scrolls through the 75 tables and there are all sorts of items in there that seem obvious after seeing them. So, I came here to re-read what I'd forgotten in the pile of diapers, baby puke and moving boxes the last 6 months have brought me.

The re-read prompted a little GM ECU Googling that I've only scratched the surface of, but it wasn't long before I couldn't help but wonder:
If there are (for example) 75 tables utilized for various functions on a single tune in an ECU, how effective is that ECU on a different engine even if it is "fully cracked"? How much of that tuning can be done driving down the street or blasting up and down the country roads* or without the aid of equipment I don't own, can't use and couldn't possibly justify purchasing?

Has you ever owned or tuned a car with an aftermarket ECU that you'd be comfortable throwing the keys to your mother to drive (power aside perhaps)? There's that old adage - if handing over the keys takes more than 30 seconds of "you need to push this, hold that and squeeze this if that happens" then you probably shouldn't be handing them over. In terms of a day-to-day driving experience, how much worse/fiddly/compromised was it over the OEM tune?

*"blasting" of course being casual Sunday-with-the-family driving of course, nothing anti-social or illegal officer

[SteveCanyon]

Has you ever owned or tuned a car with an aftermarket ECU that you'd be comfortable throwing the keys to your mother to drive (power aside perhaps)?

Yes, every one of them in fact.
For example I built a ~140kW 1.6 litre engine a while back that pretty much anyone could drive. True enough it was a bit flat below 2,000rpm but it drove much like a normal road engine.

Billzilla

[NTSOS]

Contact Jon Lund, he is the top GT500 tuner in the US and should be able to answer any questions regarding "fully cracked" OEM ECU's vs aftermarket solutions.

Lund Racing

John

[cheapracer]

True enough it was a bit flat below 2,000rpm but it drove much like a normal road engine.

Billzilla

A normal road engine these days is flat below 2000 so you were successful I would say in retaining normality...

[Canuck]

Bill - what was your ecu of choice for these projects?

The quandry for me is: Use a MS / Motec type standalone that's designed for doing just that, or taking a more powerful oem Unit designed for a GM product and trying to adapt it to my BMW.

[SteveCanyon]

Bill - what was your ecu of choice for these projects?

The quandry for me is: Use a MS / Motec type standalone that's designed for doing just that, or taking a more powerful oem Unit designed for a GM product and trying to adapt it to my BMW.

The Sprinter had a Motec M4. The Fraser has a Motec M400 as that box is needed to control the variable cam timing. The WRX is getting a new 2.5 litre engine and it'll be run by an Apexi Power FC, which again if tuned well will drive 99% like a regular road car.

If I were you and didn't want to spend a huge amount of cash I'd be looking at an Adaptonic, they're 95% as good as a Motec/Autronic but for far less cost.
www.adaptronic.com.au

Billzilla

[Greg Locock]

Wow, looks like a great product I particularly like http://www.adaptronic.com.au/comp.php -a gutsy move

[GreenMachine]

Wow, looks like a great product I particularly like http://www.adaptronic.com.au/comp.php -a gutsy move

From the linked site

"Sources
Manufacturers' websites linked to in Links and Specifications above, referenced December 2003 to November 2005
ECU Comparison, referenced December 2003"

Not very gutsy - it's 2010 for those who haven't yet noticed ...

Having said that I hear good things about Adaptronic. I run a Haltech E8, now in the racer, previously in the road/racer, and would probably stick to their new gen Platinum series. Autronic also have a good rep here, and of course Motec if you have the brass.

The general advice I have seen/got is pick your tuner first, talk to him about what you want (outcomes), and see what he advises. If you just want to run fuel and ignition that can be pretty simple (but still check you have enough outputs, especially if it is an 8 or 12 cylinder), but when you are looking at water injection, anti-lag, flat shift, launch control, etc etc you need a lot of spare I/O ports.

If it is all DIY, what about megasquirt?


My 2c.

[Canuck]

Megasquirt has been/is the front-runner for this project because I'm both incredibly "thrifty" and I have a strong preference for DIY. My trepidation comes from not knowing how well these ECUs can be tuned. What I don't want to do is take a nicely running daily driver and completely destroy it's drivability for the sake of scratching an itch. Having said that, the carb was a pretty simple device for the most part and it was on everything I owned until 2002. If a carb'd vehicle can be tuned to run sweetly, I would guess so can a standalone system.

[SteveCanyon]

If a carb'd vehicle can be tuned to run sweetly, I would guess so can a standalone system.

For sure they can, but the problem is even with the best arse-o-meter dyno you can't feel even fairly wide variations in mixture. A good engine management system will let you get the mixture pretty darn close to exactly right all the time, no matter what the temperature or altitude. There's a number of other benefits as well.

Billzilla