lookforjoe Posted November 20, 2009 Author Report Share Posted November 20, 2009 Is the 4th column still ignition timing? What's the 5th, that stays constant at 231? That's the MAF maxxed out. You seem to be making more boost in 3rd. You have way less timing at the same RPM as in 2nd. You really need to sort out a way to not be pegging the MAF. Without actual load readings there isn't much you can do right now. So, the calculated load from OBDII is not useful? I can't get injector duty cycle from OBDII, so I could add load back in... Not sure how I can resolve the MAF issue with the existing tune. If I change the MAF housing, I'll have to go straight to TT to adjust for it. Right now, I just want to optimize for the Woth tune & use that data as a baseline for the TT setup. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 20, 2009 Author Report Share Posted November 20, 2009 I'm thinking I need to make a drain back from the CC for the cam cover vent. I'm considering drilling & tapping the breather box, as I'm sure the drain is subject to siphoning; it drains into a closed section that drops below oil level, so crankcase pressure should not be exerted on that area. I believe draining back anywhere else will subject the drain to the same level of crankcase pressure I'm trying to alleviate.. Anyone got thoughts on that? drain port in block... there is a matching sleeve in the pan sample breather box with drain nipple Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 20, 2009 Author Report Share Posted November 20, 2009 4th gear pull from around 50 this morning rpm peak is 4/5 shift [ Quote Link to comment Share on other sites More sharing options...
ozzimark Posted November 20, 2009 Report Share Posted November 20, 2009 Your AFR spikes rich when you get off the throttle for the shift? I don't have a wideband yet, but I know my car goes into closed loop when the engine is at some RPM higher than idle and my foot comes off the throttle, I always assumed that it reduced flow of fuel into the engine at that time, not tried to flood it :blink: Quote Link to comment Share on other sites More sharing options...
Dave 54 Posted November 20, 2009 Report Share Posted November 20, 2009 That's the MAF maxxed out. So, the calculated load from OBDII is not useful? I can't get injector duty cycle from OBDII, so I could add load back in... Not sure how I can resolve the MAF issue with the existing tune. If I change the MAF housing, I'll have to go straight to TT to adjust for it. Right now, I just want to optimize for the Woth tune & use that data as a baseline for the TT setup. In the DSM scene we would run a GM MAF translator, not saying it would work here but there maybe others that could be modded to work? http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/174055-everything-you-want-know-about-maf-translator-maft.html Here's another to check out, http://www.maftpro.com/ Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 20, 2009 Author Report Share Posted November 20, 2009 Your AFR spikes rich when you get off the throttle for the shift? I don't have a wideband yet, but I know my car goes into closed loop when the engine is at some RPM higher than idle and my foot comes off the throttle, I always assumed that it reduced flow of fuel into the engine at that time, not tried to flood it :blink: It spikes lean on decel- it may swing full rich for a millisecond, but then it will peg 18+ - look at the timing, too - it goes close to TDC on closed throttle/heavy decel Shift is only momentary reduction in load, look at the time span & the timing advance during shift Quote Link to comment Share on other sites More sharing options...
ozzimark Posted November 20, 2009 Report Share Posted November 20, 2009 Your AFR spikes rich when you get off the throttle for the shift? I don't have a wideband yet, but I know my car goes into closed loop when the engine is at some RPM higher than idle and my foot comes off the throttle, I always assumed that it reduced flow of fuel into the engine at that time, not tried to flood it :blink: Er, I meant open loop, not closed :rolleyes: Quote Link to comment Share on other sites More sharing options...
ozzimark Posted November 20, 2009 Report Share Posted November 20, 2009 It spikes lean on decel- it may swing full rich for a millisecond, but then it will peg 18+ - look at the timing, too - it goes close to TDC on closed throttle/heavy decel Shift is only momentary reduction in load, look at the time span & the timing advance during shift heres a crop from the csv file I've seen the stock timing map for out engines, 0 and 5% load rows have timing values in the single values or low teens, so that makes sense that the timing retards to almost TDC, I don't see the lean spike you're referring to though, only that it's going down to ~10:1 as soon as you shift, and then comes back up a little less than a second later. I guess that basically is a split second :lol: Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 20, 2009 Author Report Share Posted November 20, 2009 I've seen the stock timing map for out engines, 0 and 5% load rows have timing values in the single values or low teens, so that makes sense that the timing retards to almost TDC, I don't see the lean spike you're referring to though, only that it's going down to ~10:1 as soon as you shift, and then comes back up a little less than a second later. I guess that basically is a split second Sorry, lean spike is on decel/off load, not on shift points - you can see the MAF doesn't change there... yeah - more like half a second on the timing/AFR change Quote Link to comment Share on other sites More sharing options...
EricF Posted November 20, 2009 Report Share Posted November 20, 2009 I've seen the stock timing map for out engines, 0 and 5% load rows have timing values in the single values or low teens, so that makes sense that the timing retards to almost TDC, I don't see the lean spike you're referring to though, only that it's going down to ~10:1 as soon as you shift, and then comes back up a little less than a second later. I guess that basically is a split second Your thoughts on timing are off quite a bit If you follow a stock map's 25% line, it will start at 15 degrees for the 500 RPM bin, and climb to 37 degrees by the last bin. The 100% line starts at 12 and climbs to 26... The last bin is 6200 RPM btw. Especially in the higher RPM range as you get further away from the torque peak, you need quite a bit of timing even on small fast burning chambers like these with centered spark plugs. Here is my current timing map, I think it is a little too conservative in a few places. (I'm running 17-19 psi boost, so at WOT by 4000 I'm in the 200-230 KPA range. I have a suspicion Hussein's datalogger is lying to him about timing. Or else it's all being pulled for some reason. Quote Link to comment Share on other sites More sharing options...
Captain Bondo Posted November 20, 2009 Report Share Posted November 20, 2009 It spikes lean on decel- it may swing full rich for a millisecond, but then it will peg 18+ - look at the timing, too - it goes close to TDC on closed throttle/heavy decel Shift is only momentary reduction in load, look at the time span & the timing advance during shift Ugh. No. Engines go rich on decel. The lean spike is actually a (normal) rich misfire. Are you sure your analysis of the timing is not backwards, it makes more sense that it's going to 30 when you let off and down to ~5 when you are wot. Assuming that the numbers look fine to me. Again, since it is pegging the maf, you really have no actual way of knowing how the ecu is determining required ignition advance past that point. That advance seems reaosnable based on your boost pressure though. It might take some more up high in the revs, but you won't tune that without a dyno and a programmable system. Eric your map is way conservative based on my experience. Get to the dyno. :D Quote Link to comment Share on other sites More sharing options...
550 Posted November 20, 2009 Report Share Posted November 20, 2009 Is there a way to go with a MAP sensor on the USB TT? Maybe the goofiness is due to the MAF? Also, yeah my car goes to almost straight O2 on decel. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 21, 2009 Author Report Share Posted November 21, 2009 Ugh. No. Engines go rich on decel. The lean spike is actually a (normal) rich misfire. Are you sure your analysis of the timing is not backwards, it makes more sense that it's going to 30 when you let off and down to ~5 when you are wot. Assuming that the numbers look fine to me. Again, since it is pegging the maf, you really have no actual way of knowing how the ecu is determining required ignition advance past that point. That advance seems reaosnable based on your boost pressure though. It might take some more up high in the revs, but you won't tune that without a dyno and a programmable system. Sorry, I thought that's what I said - it certainly is that way on the graphs. Not much I can do with it now, so I'll just record some more & then swap to the TT ECU & go from there.... Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted November 21, 2009 Author Report Share Posted November 21, 2009 Bought a Cusco CC, based on searching several websites, they all claimed it was a baffled can - guess what - it's not The seller has refunded me some of the purchase price, so I cut it open to add my own baffle. I'm going to use this for the cam cover vent & drain back to the block. Vent line will go to the other CC. Quote Link to comment Share on other sites More sharing options...
turbotuner Posted November 21, 2009 Report Share Posted November 21, 2009 Is there a way to go with a MAP sensor on the USB TT? No I don't think so, unless you use some sort of MAF to MAP conversion system. But why would you want to anyway? Also, yeah my car goes to almost straight O2 on decel. That is normal. Quote Link to comment Share on other sites More sharing options...
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