B C Posted April 7, 2013 Report Share Posted April 7, 2013 I am fascinated by EFI systems and am constantly studying them to try and one day have a perfect understanding of everything going on inside an ECU. This is a thread to ask questions about how EFI works, share knowledge, ideas, and theories. Discuss. Quote Link to comment Share on other sites More sharing options...
0 Jeff Posted April 7, 2013 Report Share Posted April 7, 2013 i wish i knew how an inanimate object can do so much. Quote Link to comment Share on other sites More sharing options...
0 KaiserRolls Posted April 7, 2013 Report Share Posted April 7, 2013 I can do carbs, EFI is too much for my small brain Quote Link to comment Share on other sites More sharing options...
0 Jeff Posted April 12, 2013 Report Share Posted April 12, 2013 any info on this yet? Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 12, 2013 Author Report Share Posted April 12, 2013 Well for starts, theres processor speed. Merl is upgrading his e28 to run on Motronic 1.3 which is better than the original e28 ECU for a few reasons but one of the main reasons is that Motronic 1.3 has a faster processor. It could be either a 12, 16, or 20 MHz processor (tech sheet online calls out all 3 speeds). Based on my experiences with MS2 already, I would guess that its the 16 MHz processor. Megasquirt 1 is 8 MHz but it only operates fueling, not timing.Megasquirt 2 is 24 MHzMegasquirt 3 is 50 MHz1 MHz = 1 million calculations per second. The more calculations a computer processor can do, the more things it can do at once, and the more accurately it can do those things. but yes, this thread is mainly for things to be discussed, ideas, questions asked and answered, for those who want to know more ( including myself) anyone can feel free to answer things they have knowledge about and hopefully we can all learn something about such a complex and awesome topic Quote Link to comment Share on other sites More sharing options...
0 Jeff Posted April 12, 2013 Report Share Posted April 12, 2013 i understand how the fuel injection works and pulses but dont get the ecu part of it Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 12, 2013 Author Report Share Posted April 12, 2013 be more specific good sir Quote Link to comment Share on other sites More sharing options...
0 KaiserRolls Posted April 12, 2013 Report Share Posted April 12, 2013 be more specific good sir all of it. explain all of it Quote Link to comment Share on other sites More sharing options...
0 Brian. Posted April 12, 2013 Report Share Posted April 12, 2013 all of it. explain all of it Chuckle. Is there any possible way to overclock an ECU in a car, such as in a computer? If so, you could squeeze out a bit more proccessing power. Might be a stupid question, but ECU wise. I'm about as knowledgable as Rowley is at life. Not much. YoungCR 1 Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 12, 2013 Author Report Share Posted April 12, 2013 Yes you can overclock an ECU processor for a faster processing speed. How? I am not entirely sure. Maybe someone good with computers can chime in on how this might be done on an ECU since you dont really get a BIOS interface on a factory ECU like you do with a PC Quote Link to comment Share on other sites More sharing options...
0 Brian. Posted April 12, 2013 Report Share Posted April 12, 2013 Yes you can overclock an ECU processor for a faster processing speed. How? I am not entirely sure. Maybe someone good with computers can chime in on how this might be done on an ECU. I'm good with computers. But I can't see an ECU having a sort of "OS" that's navigatable.Overclocking a normal PC is alot easier then you'd think. I feel it's doable. But it'll shorten the life of the ECU to a really short span. Quote Link to comment Share on other sites More sharing options...
0 240sxguy Posted April 12, 2013 Report Share Posted April 12, 2013 There isn't any reason to overclock an EFI system IMO, if it's not fast enough to do what it needs to do it needs to be upgraded. An automotive environment is very harsh and I would want a processor loafing along as cool as possible given the choices. Quote Link to comment Share on other sites More sharing options...
0 Brian. Posted April 12, 2013 Report Share Posted April 12, 2013 So, from what I've been reading online (in the 10 minutes in between) 3000GT VR-4 owners, it's sort of common to "overclock" your ECU, it'll raise the rev-limit, and advance timing. AE86 owners- not really an option. A few have done it, you change a "crystal" (what?) and it'll up the rev-limit as well. And *CAN* help with stage 2 or higher cam durations. Here's a neat read as well: http://forums.nasioc.com/forums/showthread.php?t=1736906 That's subaru related. Yet to find anything BMW related. It has been my experience that proprietary computer devices/controllers don't respond predictably to clock speed increases. Dependant on the design of the entire system, certain functions can depend on cpu clock speed and timing issues can develop when it changes. Mostly this manifests itself in I/O operations. If the cpu is waiting for a response from an external device and is programmed to wait x-amount of clock cycles or generate an error, when the clock cycles are sped up and the external device still responds at it's original speed, problems... This may or may not be the case with the Bosch ECU but in NC machinery, it's definitely an issue. That was taken off a TDi forum. So, I guess it's safe to say. That yes you can overclock an ECU, but the work-to-reward isn't really there. At that point, you might as well go open source! Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 12, 2013 Author Report Share Posted April 12, 2013 Must be like the crystals that you use on RC car radios to change frequencies I could see overclocking being a sort of novelty computer geek project coupled with a piggyback or some signal controllers so that you could manipulate a stock ECU but theres definitely no NEED to do so when Megasquirt exists. fun fact for computer geeks: The Siemens MSS54 ecu in the E46 M3 is a 32 bit dual core processor. Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 12, 2013 Author Report Share Posted April 12, 2013 There isn't any reason to overclock an EFI system IMO, if it's not fast enough to do what it needs to do it needs to be upgraded. An automotive environment is very harsh and I would want a processor loafing along as cool as possible given the choices.This is a good point. I'd rather be sitting in my office and have my PC fail from an overclocked processor than be in my car out in the boondocks with a toasted ECU Quote Link to comment Share on other sites More sharing options...
0 YoungCR Posted April 13, 2013 Report Share Posted April 13, 2013 I've gotten very interested in EFI, something I definitely wanna do down the road but I'm gonna try getting it running on the original L-Jetronic first Quote Link to comment Share on other sites More sharing options...
0 B C Posted April 13, 2013 Author Report Share Posted April 13, 2013 L-jet is a nice simple system and easy to maintain. Let me know if you have any issues with getting yours to run nice and crisp. I was compelled to learn all about L-Jet on my E30 since it misfired, hesitated, bogged, and barely ran when I first got it. YoungCR 1 Quote Link to comment Share on other sites More sharing options...
0 B C Posted May 14, 2013 Author Report Share Posted May 14, 2013 This is what 4 degrees of timing advance @ full throttle was worth on todays tune run. Quote Link to comment Share on other sites More sharing options...
0 KaiserRolls Posted May 14, 2013 Report Share Posted May 14, 2013 ^ good thing we can all see that photo Quote Link to comment Share on other sites More sharing options...
0 B C Posted May 14, 2013 Author Report Share Posted May 14, 2013 Nice try at rustling my jimmies. Quote Link to comment Share on other sites More sharing options...
0 B C Posted May 14, 2013 Author Report Share Posted May 14, 2013 And here is where I am at today with some fuel adjustments vs. my baseline run (Tune A). The AFRs are getting better and better. I recorded a few datalogs to sit down and disect tonight so that I can make preparations for the next tuning session. I know there is some more power to be found though. Quote Link to comment Share on other sites More sharing options...
0 KaiserRolls Posted May 14, 2013 Report Share Posted May 14, 2013 it blows my mind how many hidden hp's can be found just by tuning. nice work Brian Quote Link to comment Share on other sites More sharing options...
0 Brian. Posted May 14, 2013 Report Share Posted May 14, 2013 EFI amazes me. Tunes do Subaru's HUGE wonders. BMW's can pick up a pretty noticable gain. But the vehicle I've noticed that picks up the most notable gain in HP/tq and smoother power climb, is subaru's and porsches. Dunno why, but they can really pick up a nice amount with a good tune. Even all factory Quote Link to comment Share on other sites More sharing options...
Question
B C
I am fascinated by EFI systems and am constantly studying them to try and one day have a perfect understanding of everything going on inside an ECU.
This is a thread to ask questions about how EFI works, share knowledge, ideas, and theories.
Discuss.
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