Guest z1 performance Posted June 18, 2003 Share Posted June 18, 2003 Car is running great with the exception of idle.....the cam is, well, a bit aggressive (610 lift, 300 duration), injectors are 480's, no ISC at all...I can get it to maintain a solid 1250-1300 but the AFR is rich (12.5:1 range), or I can get it to idle down to 1000 on the nose, but AFR is very lean (as in 18:1 and higher). I run without the 02 turned on, etc...any "base maps" out there to start with? Sparkplugs are still stoch heat range for right now (till the motor is fully broken in). As it stands, my TOG is at 8, and on the VE table I am running -35 at idle. Timing at idle (per the timing table) is at 18 degrees, but I could not tell you if thats a true 18, or if its + or minus a bit (no timing marks on the pulley setup ) I know its a stretch, but was hoping someone might be able to educate as to which way I should be going...or whether I seemingly have it pretty good as it sits. I always had relied on my partner here at the shop to do the tuning on the TEC< but he is not around much, and I want to educate myself as much as possible in its ins and outs. I have used standalone many times before in other applications, but never on such a "hardcore" setup (ie big cams, no idle control, closed loop etc) TIA guys! Adam Quote Link to comment Share on other sites More sharing options...
TimO Posted June 18, 2003 Share Posted June 18, 2003 Adam- Is your engine a Chevy small block, Nissan L6, turbocharged, na, ??? The -35 you're running for idle ve, is that -.35 or -.035, hopefully its -.035? Regards TimO Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted June 18, 2003 Share Posted June 18, 2003 Hehe..sorry Its an L28 motor. At idle on the VE table, its at a -35..maybe I have been doing it incorrectly (and if so, please help!), but essentially what we did was run the setup through the autosetup, and it gave us the starting numbers, and we played from there. TOG is now at 8.125, which to my understanding is the IPW in milliseconds at 0 psi, so you are adding and subtracting from there whether you are in boost or vacuum. To do this, we have been basically adjusting the VE table upwards and downwards at various rpm points and MAP loads. Max boost the car will see for the time being is 14 psi, unless we can ring some more out of the current injectors. At idle, VE is -35, at WOT full boost, its at +35, which to me made sense...runs 35% less IPW at idle than it does at 0 psi boost, and runs 35% more IPW at WPT, full boost. Am I looking at it wrong? Quote Link to comment Share on other sites More sharing options...
240Z Turbo Posted June 19, 2003 Share Posted June 19, 2003 Adam, typically you do not want to have such big swings in your VE #'s as this indicates your IOT and TOG are not set correctly. Let us say your VE at full boost and high rpm is .5 and you run a TOG of 8. In order not to have such big changes in your VE values you should change your TOG value to 8+[.5 x 8]=12. In your case it would be 8+[.35 x 8]=10.8. I typically just set my TOG to about 11 or so. You should also have the firing set to alternating divide by 1. Now, you should not be having to take out 35% at idle either. Set the TOG to 11 and clear the VE table. With the VE table zero'd lower the IOT until it gets your idle close. BTW, you can have negative values for IOT and mine is currently to about -1.375. With the newly set IOT and TOG values your VE table should have much smaller changes from idle to WOT. Although you can use big corrections as you have, +/- 35% it is not the best method. Anyway, this does not cure your idle issue. There is nothing wrong with idling the car at 18:1 if the car idles well at 18:1. My car will idle and cruise at 16:1-17:1 all day long. From what I have seen with OEM cars they sit in the 15.5:1-16:1 when idling and cruising. Here is a good question, how much vacuum are you getting at idle with this cam? Quote Link to comment Share on other sites More sharing options...
240Z Turbo Posted June 19, 2003 Share Posted June 19, 2003 BTW, I don't know about tuning full boost stuff to 12.5:1. Even most of the Honda Turbo and other turbo stuff we dyno it never goes leaner than 12.2:1. I think with the combustion chamber design you should try to stay atleast 12:1. If you are more conservative on the timing you can go leaner, but I personally like more timing and more fuel. I typically tune my setup to 11.6:1 or so. BTW, my buddies turbo mustang runs 11.6:1 for max power and it recently ran 7.78@180. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 19, 2003 Share Posted June 19, 2003 Hehe..sorry At idle on the VE table' date=' its at a -35..maybe I have been doing it incorrectly (and if so, please help!), but essentially what we did was run the setup through the autosetup, and it gave us the starting numbers, and we played from there. TOG is not at 8.125, which to my understanding is the IPW in milliseconds at 0 psi, so you are adding and subtracting from there whether you are in boost or vacuum. To do this, we have been basically adjusting the VE table upwards and downwards at various rpm points and MAP loads. Max boost the car will see for the time being is 14 psi, unless we can ring some more out of the current injectors. At idle, VE is -35, at WOT full boost, its at +35, which to me made sense...runs 35% less IPW at idle than it does at 0 psi boost, and runs 35% more IPW at WPT, full boost. Am I looking at it wrong?[/quote'] A little bit - TOG is the injector pulsewidth at whatever your MAP sensor's max range happens to be (i.e., if you have a 3 bar MAP sensor, then TOG is the IPW at 312kPa). James and TimO already covered it pretty well, but the spread that you are showing in your VE table suggest that your IOT and TOG values are not ideal. IOT and TOG determine the y-offset and slope (respectively) of your base fuel curve. I did a bit of poking around, and similar to James, I think you should change you IOT to -1.25 and change your TOG to 12.5. This should compensate both ends of your VE table and get your corrections closer to zero. I agree with James that there is nothing inherently wrong with running 18:1 at idle - most people seem to have more problems getting their cars to idle with mixtures approaching 14.6, let alone that much leaner. If it's stable at that mixture, I'd be inclined to leave it alone. If you want to run closed loop at idle, you can always set the target AFR to match. Were you having a specific problem with your idle settings, or were you just looking for a warm fuzzy feeling about the settings you have? Quote Link to comment Share on other sites More sharing options...
TimO Posted June 19, 2003 Share Posted June 19, 2003 James and TimZ covered it all......good luck Adam. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 19, 2003 Share Posted June 19, 2003 TOG is the injector pulsewidth at whatever your MAP sensor's max range happens to be (i.e.' date=' if you have a 3 bar MAP sensor, then TOG is the IPW at 312kPa). [/quote'] Oops - this assumes that you have an IOT of 0. Actually, TOG + IOT gives you the IPW at the MAP sensor's max output. If you use the standard equation for defining a straight line: y=mx +b y is the IPW m is TOG x is MAP b is IOT Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted June 20, 2003 Share Posted June 20, 2003 I got it now, thanks guys..will start playing with the settings again tomorrow and will let you know how it goes (maybe I'll post some logs here if you guys want to take a look). Do you guys bother to tune using the MAP/TPS blend, or do you find that simply tuning each by feel gets you pretty close? Driveability ios very good on mine as it sits, but again, I have not used the blend feature at all. As for AFR, it is only 12.5 at idle...not at WOT. Right now at full boost, the highest AFR I see is 11.6:1. Of course the other issue is the timing.....there are no marks on my pulley anymore, so its basically an eductaed guess as to where base timing is starting......I think that will be next weeks project, as I want to know exactly what everything is doing. Vacuum at idle is pretty strong actually....right around 500 mmHg (my gauges are all metric) Adam Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 20, 2003 Share Posted June 20, 2003 Do you guys bother to tune using the MAP/TPS blend' date=' or do you find that simply tuning each by feel gets you pretty close? Driveability ios very good on mine as it sits, but again, I have not used the blend feature at all. [/quote'] The blend function is intended for engines with really wild cams that exhibit very noisy MAP signals at idle. If your MAP signal looks clean at idle you probably don't need to mess with the blend function. Your cam does sound pretty aggressive, but it doesn't sound like you have had much trouble without using the blend function so far. I would only mess with that as a last resort - there is very little expertise out there on the blend function and it's not very striaghtforward to setup, so you'll be pretty much on your own. Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted June 20, 2003 Share Posted June 20, 2003 I hear what you are saying...MAP is actually dead stable at idle even with the big cam Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted July 5, 2003 Share Posted July 5, 2003 Just a quick update guys.....upon further inspection, at TDC my crank pulley was around +12 advanced, so I scaled my timing cirve back by that amount...did not notice any changes in terms of loss of power or loss of spool, nor did my AFR's change significantly at all, which I found a bit odd. I set TOG to 12.5, but in order to get it to sustain an idle IOT has to be in the -1.65 range. Biggest problem at that point was running WAY to much fuel from 3000 rpm upwards, so had a fair amount of tuning left to do....and of course its 95 degrees here today and I am by myself, so not exactly the ideal tuning conditions I plan on jetting back out to the shop in the AM after the F1 race and see how much more I can get done before it gets really hot out Would someone with a remote similar setup (big FMIC, 480 injectors, etc.) mind emailing me the map they most often run for pump gas....would save loads of time....I'd greatly appreciate it! Also, do you guys tend to use the autocalculate for the VE table after doing datalogs, or just constantly datalog, tune, datalog, tune. And lastly, does everyone run with 02 feedback on or off? Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted July 6, 2003 Share Posted July 6, 2003 Update # 2 Spent the better part of today logging and mapping again (oh joy..I knew I didn't miss this!), and I got a very good map going. I am still making adjustments to the VE table, but only because its the only combo I got to work today. As of right now, TOG is at 11.5, IOT is at 1.425, though I still am making +/-10-12% corrections on the VE table. I tried taking the corrections down and altering TOG and IOT but I could not get the right combo, so as of right now, its going pretty well. On 93 octane, at 14 psi, I am hitting a max IDC of just 76%, so I could either turn up the boost or lean it out a bit more. Max timing advance is 32 degrees, tapering down to 24 at redline and full boost. Even with that agressive of a map, I still am only seeing 11.4 as my leanest AFR under boost, and it gets down to the high 10's at higher rpms. Probably way too rich, but I still have not managed to locate my wideband yet (you know how it goes....3 years ago you HAD to have it, now you can't even find it!). Hopefully in the next week or 2 we can get it out to the track, use some race gas and see what she'll do. Quote Link to comment Share on other sites More sharing options...
Guest z1 performance Posted July 12, 2003 Share Posted July 12, 2003 bump Quote Link to comment Share on other sites More sharing options...
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