JCviggen Posted January 29, 2010 Report Share Posted January 29, 2010 Fine, I'll make a video of the M4.3 map trace at part throttle and full throttle at similar boost. Why are you arguing about an EMS you're not even using yourself? I agree with your basics but they are irrelevant to the "pegging the MAF" problem which isn't one. Pegging the MAF or not it can be perfectly tuned to have a correct AFR between no throttle and full throttle at any boost and RPM point as long as you don't change max boost at WOT. What the fuck does all the other crap matter? Quote Link to comment Share on other sites More sharing options...
GeraldJ Posted January 29, 2010 Report Share Posted January 29, 2010 LOL, I love this thread! I think Cpt. Bondo might be confused as to how TT works. It allows adjustment acording to load and rpm given a set boost limit. Correct me if I am wrong. Flame suit on and armed LOL, I love this thread! I think Cpt. Bondo might be confused as to how TT works. It allows adjustment according to load and rpm given a set boost limit. Correct me if I am wrong. Flame suit on and armed :excl: Quote Link to comment Share on other sites More sharing options...
EricF Posted January 29, 2010 Report Share Posted January 29, 2010 Fine, I'll make a video of the M4.3 map trace at part throttle and full throttle at similar boost. Why are you arguing about an EMS you're not even using yourself? I agree with your basics but they are irrelevant to the "pegging the MAF" problem which isn't one. Pegging the MAF or not it can be perfectly tuned to have a correct AFR between no throttle and full throttle at any boost and RPM point as long as you don't change max boost at WOT. What the fuck does all the other crap matter? Jan I think you just need to take some datalogs. Do you have a wideband AFR channel in your datalogging? Kenny, I know that what you are saying given all of the information at hand is a no-brainer truth. However, there are hundreds of cars running Motronic at more than 270 bhp... I have not had an 850 with less than 270 bhp in probably 5 years. I've had wideband air/fuel on the last two, with various hardware setups and they have also been my highest output setups. I think someone would have piped up since 850s have been introduced if making big power with the stock EMS somehow seriously fucked up even a certain aspect of the car's drivability. Charles has had a 110 trap 850 since 1999 or so, with Motronic tuning done through the mail. It's not his daily driver but it was at one point. I had a car that was my daily for about two years that trapped in the 105-107 range every time it went to the track, I had wideband air/fuel monitoring and in every condition the values were good. Ben (torquesteer) has a Hahn big 16G 850 that traps 105ish and has been daily driven on that setup for about 3 years now. Jan has had a pretty well-sized turbo on his car for a couple of years now and has raced on the Nurburgring quite a bit. He should know better than anyone about part-throttle mid-high boost situations... These are only a few cars that I know the owners fairly well and know the cars have seen a LOT of miles with high output and motronic. When the theory doesn't agree with the real world, then the theory is being formed with incomplete or incorrect information. The real world can't be declared wrong because the known variables don't add up. It's really the other way around... Quote Link to comment Share on other sites More sharing options...
flaco Posted January 29, 2010 Report Share Posted January 29, 2010 I have to say that if these engines used a MAP system, then the bent rods might be easily avoidable.... And true, motronic works fine, even tho I don't like the way it handles the MAF (and why Im going megasquirt a-la plug-n-play inside a stock ecu case) BTW the map sensor is inside the ecu, so all I need is a hose from the map to the vacuum tree. No big issues here. Quote Link to comment Share on other sites More sharing options...
turbotuner Posted January 29, 2010 Report Share Posted January 29, 2010 I have to say that if these engines used a MAP system, then the bent rods might be easily avoidable.... Bent rods can be avoided using a MAF system too!!! TT has adjustable air-flow limits for precisely this reason. Sensible tuning is the best way to avoid bent rods. Quote Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 30, 2010 Report Share Posted January 30, 2010 When the theory doesn't agree with the real world, then the theory is being formed with incomplete or incorrect information. The real world can't be declared wrong because the known variables don't add up. It's really the other way around... This discussion is and will continue to be meaningless and go in circles until someone just explains how Turbotuner/Motronic 4.x actually calculates injector pulsewidth. If someone who knows would explain it, I think lots of people would benefit, because it's clear there is a lot of misunderstanding going on. I'm just basing my comments on how most MAF based ECU's operate. If I don't have all the facts, fine, but enlighten me rather than just saying I'm confused or don't know the facts. Quote Link to comment Share on other sites More sharing options...
flaco Posted January 30, 2010 Report Share Posted January 30, 2010 This discussion is and will continue to be meaningless and go in circles until someone just explains how Turbotuner/Motronic 4.x actually calculates injector pulsewidth. If someone who knows would explain it, I think lots of people would benefit, because it's clear there is a lot of misunderstanding going on. I'm just basing my comments on how most MAF based ECU's operate. If I don't have all the facts, fine, but enlighten me rather than just saying I'm confused or don't know the facts. Hence my comment on my MS thread that the motronic code isn't yet fully understood.... Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted January 30, 2010 Author Report Share Posted January 30, 2010 I think to replace the maf with a map you'd need to use a maf eliminator kit that also involves a second IAT senssor. It would have to use the IAT and MAP to send out an "equivalent" load signal (the MAP signal would need to be density corrected). Maybe I'm missing something, but in my data logs you can see the AFR change in response to boost pressure changes even if the MAF is maxxed out... What I'm trying to resolve is the heavy rich spot in the 4-5K range somewhere in the 40-80% range in 4-5th also need to smooth the start duty cycle of the boost solenoid to reduce the spikes after shifting Quote Link to comment Share on other sites More sharing options...
flaco Posted January 30, 2010 Report Share Posted January 30, 2010 Exactly, AFR will change because (correct me if Im wrong) motronic sends a 'fixed' signal to the injectors when the MAF is maxed out, EVEN if your boost is changing. Quote Link to comment Share on other sites More sharing options...
EricF Posted January 30, 2010 Report Share Posted January 30, 2010 If I don't have all the facts, fine, but enlighten me rather than just saying I'm confused or don't know the facts. I wish I could, Motronic's calculations are a big gray area for the most part. I really wonder what possible variables could be considered to keep things kosher after the MAF is maxed out. My post was more to say that we really don't understand exactly what's going on, but something is going on that works. Quote Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 30, 2010 Report Share Posted January 30, 2010 If no one here can say something like Pulsewidth = Load*Map-point + K1*IAT + K2*CLT + K3*MAP or something then nobody knows what's actually happening unless you can datalog or scope injector pulsewidth. Quote Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 30, 2010 Report Share Posted January 30, 2010 I My post was more to say that we really don't understand exactly what's going on, but something is going on that works. You of all people should be beyond this sort of reasoning by now. Sure maybe it "works". Look how many years everyone on tbricks said the 90+ "works". Now it's a given that the 90+ leaves a lot of power on the table. Even guys making bigger power like Peter L that were used as "proof" that the 90+ "works" eventually converted and picked up like 50whp and would never say that now. The bottom line is even the fastest cars here have mediocre power outputs compared to what most guys with other makes are doing, and they bend rods very easily. Nobody even seems to know how the basic engine control works and you're all blaming the rods. The fact that most are convinced convinced that the rods suck and bend on their own and aren't even very safe for 300whp speaks volumes. I'd be shocked if the rods weren't good for 350-400whp but the way things are "tuned" around here is so FUBAR'd no one will ever realize it. Based on my motor I've already shown they're quite happy around 325whp (based on the hp per rod my motor makes) and I only stopped because I ran out of fuel. Sure blame it on a bigger hotside and no "low rpm boost spike" if you want, but the bottom line are there are some basic issues going on that no-one can seem to define that are holding most guys up bigtime. If you don't wanna hear it then fine but I'm trying to make a point not just be an asshole. :) 1 Quote Link to comment Share on other sites More sharing options...
cr854r Posted January 30, 2010 Report Share Posted January 30, 2010 spot on Quote Link to comment Share on other sites More sharing options...
EricF Posted January 30, 2010 Report Share Posted January 30, 2010 You of all people should be beyond this sort of reasoning by now. Sure maybe it "works". Look how many years everyone on tbricks said the 90+ "works". Now it's a given that the 90+ leaves a lot of power on the table. Even guys making bigger power like Peter L that were used as "proof" that the 90+ "works" eventually converted and picked up like 50whp and would never say that now. The bottom line is even the fastest cars here have mediocre power outputs compared to what most guys with other makes are doing, and they bend rods very easily. Nobody even seems to know how the basic engine control works and you're all blaming the rods. The fact that most are convinced convinced that the rods suck and bend on their own and aren't even very safe for 300whp speaks volumes. I'd be shocked if the rods weren't good for 350-400whp but the way things are "tuned" around here is so FUBAR'd no one will ever realize it. Based on my motor I've already shown they're quite happy around 325whp (based on the hp per rod my motor makes) and I only stopped because I ran out of fuel. Sure blame it on a bigger hotside and no "low rpm boost spike" if you want, but the bottom line are there are some basic issues going on that no-one can seem to define that are holding most guys up bigtime. If you don't wanna hear it then fine but I'm trying to make a point not just be an asshole. And that's a big reason of why I went to standalone. I've always underachieved on virtually all of my setups, and a big reason is because of Motronic and the lack of tuning options for it (well, lack of success with most of these tuning options). I've finally broken out of the limitations of the stock EMS, and I am hoping once I do some tuning on my car with stock longblock (including cams), stock clutch, stock manifold stock intercooler, it will become very apparent that Motronic itself and our tuning options as a community have been a big limitation. As far as the "weak" rods or rods bending easily, as far as I'm concerned it's operator error as much as anything else. About a year ago in a high traffic thread about someone with bent rods, I asked if any of the people posting actually even knew what detonation sounded like... Needless to say I was actually explaining that. There's a lot of carriage before the horse around here. I have never personally bent a rod, and on my first big turbo setup, I was running 20+ psi with an off the shelf tune and running rich, and made a thread asking how people bend rods because I was beating the shit out of my car with no ill effects. That car was also not nearly as fast as it should have been. I do think that a bigger hot side and later powerband and boost curve is of huge benefit to these cars. It's also really anemic to drive with the stock auto But there is some resolution or response issue with the EMS in my opinion, when you get very high boost levels building very quickly at low RPM. Not only that, but the 19T has a big problem with boost control if you start going over 20 psi. When my car was running 20-21 psi peak boost with the 19T, it would hold that boost level dead steady from 3500 RPM until redline. Before 3000 RPM with too much throttle it would spike to 24-26 psi *sometimes* and sometimes not. I'm neurotic about watching gauges and never let anything bad happen, but I could see how someone might not notice and run lean on a boost spike and ping and bend a rod. That was with two different types of MBC's, and a Profec B spec 2. I gave up after that and just stopped flooring it below 3500, then went to a bigger turbo. Apparently this issue doesn't come up on everyone's setups and I'm sure it has to do with a lot of factors. Your point is well taken and I take that role here pretty often. However it is why I encourage simple setups like known 'decent' maps and mild turbos like the 18T for 99% of people here, because if they don't even know what detonation sounds like or have basic understandings of a lot of things, it's something that will get them 30-40 whp over stock and be pretty damn reliable without much room to mess it up. I've been planning a big revision to my pinned thread for quite a while now, I have just been waiting to really tap into this current setup's potential and get some hard numbers first ;) Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted January 30, 2010 Author Report Share Posted January 30, 2010 the rich spot.. about 1/2 sec in duration here, unlike the previous highway pull 1/2 a sec in this highlighted section & gauge shots ..it'll do it in any gear, if I hit that exact load point. I'm just not sure what part of the map to lean out, since using Map Trace, the indicator bounces around these areas circled below, and pops over to the 90/100% cells in 4200/4800 (I leaned out the 4800 over 50% load range again by 5%) ? Quote Link to comment Share on other sites More sharing options...
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