Supra_Nish Posted May 8, 2005 Share Posted May 8, 2005 Hey all, Had the car stuck on a dyno. Could someone please take a look at the AFRs for me and let me know if it looks safe? The car was running 1.1bar, hybrids with full decat and walbro. Sorry for the poor quality pics. Thanks in advance! Link to comment Share on other sites More sharing options...
imi Posted May 8, 2005 Share Posted May 8, 2005 Nish...That fuelling looks similar to Homers so I reckon its good... Makes me wonder why mine is all over the place...perhaps I need to ZERO out all the settings on my Apexi SAFC since you guys are using the STOCK ECU despite being fully Decatted. Link to comment Share on other sites More sharing options...
Supra_Nish Posted May 8, 2005 Author Share Posted May 8, 2005 I cant remember if you said you had a walbro fitted? Maybe thats why? I think Homer said his fuel regulator helped him out. Is there a certain band of figures you want to be in under full boost? i.e. between 11 and 12 for example. Tried searching but nothing definitive. And again, anyway of knowing if its ok to up the boost form this graph, or is it a case of increasing it then dyno again to see hows it doing? So many questions! Feed me techie stuff tech gurus. I must learn Link to comment Share on other sites More sharing options...
Ian C Posted May 8, 2005 Share Posted May 8, 2005 Looks fine to me. Apparently the best power on a forced induction engine, on boost, at high revs, is at 12.7:1 or thereabouts. But you'll get similar power at 11.7:1 and it's safer - any leaner than 12.7 and you'll edge into detonation territory for running too lean. Any richer than 11:1 and you start losing power, get to the 9:1's and you'll start getting misfires as the mixture is too rich to burn properly. -Ian Link to comment Share on other sites More sharing options...
imi Posted May 8, 2005 Share Posted May 8, 2005 Great post IAN. Would explain why I still get some misfiring just about when the 2nd turbo comes on. Can you have a look at mine too and comment. http://www.zen26392.zen.co.uk/Supra%20Pics/08052005%20-%20DYNO%20DAY/SUPRA%20AFR%2010th%20May%20-%20resized.JPG here are my Apexi SAFC settings. Setting / RPM CORRECTION @ HIGH THROTTLE 1000------- 0 2000------- 0 3000------- 1 3500------- 2 4000------- 3 5000------- 5 6000------- 5 7000------- 5 Link to comment Share on other sites More sharing options...
Supra_Nish Posted May 9, 2005 Author Share Posted May 9, 2005 Thanks Ian. Link to comment Share on other sites More sharing options...
Ian C Posted May 9, 2005 Share Posted May 9, 2005 Imi - That graph says nothing about your misfire, your afrs around 4000rpm are normal. It's running too rich at the top end though, I hate to say it but if those are +ve airflow adjustment figures on your SAFC you probably need to zero them -Ian Link to comment Share on other sites More sharing options...
Dragonball Posted May 9, 2005 Share Posted May 9, 2005 Imi - There's an echo round here...there's an echo round here...! Link to comment Share on other sites More sharing options...
imi Posted May 9, 2005 Share Posted May 9, 2005 Nice one Paul & Ian......as of midnight last night (yes, it was playing on my mind). I have ZERO'D all the top end settings..... I should have done this yesterday and put is straight back on the rollers to see the difference. Car is still not idling fine....perhaps I need to get the plugs checked again...and the o2 sensor. Link to comment Share on other sites More sharing options...
Dash Rendar Posted May 10, 2005 Share Posted May 10, 2005 Sorry to jump on the bandwagon, but can someone tell me if this looks okay? Maybe a bit rich? As you'll probably all have heard by now, I did forget to done of the aircon, so I'm not sure how much that affects the AFR. As a side issue, does anyone know exactly how much the aircon affects the dyno, because I'm well depressed!! Link to comment Share on other sites More sharing options...
imi Posted May 10, 2005 Share Posted May 10, 2005 Judging by the replies that both supranish and myself have received on this thread...i would say 12.0-12.5 is what the AFR should be on boost. Link to comment Share on other sites More sharing options...
Chase Posted May 10, 2005 Share Posted May 10, 2005 Ahhhh, so it's the other way round? I thought I was running lean on boost, but it looks like I'm running rich... http://www.mkivsupra.net/vbb/attachment.php?attachmentid=10750 Link to comment Share on other sites More sharing options...
imi Posted May 10, 2005 Share Posted May 10, 2005 12.5-1 is leaner than 12.0-1 Link to comment Share on other sites More sharing options...
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