jevansio Posted June 27, 2007 Share Posted June 27, 2007 Just wondering about what RPM you idle smoothly when running the AEM ECU, could you please also state if you have lightweight flywheel, lightweight internals & cams (I'm more interested in these ones as that's my spec). I've got mine very smooth at 1000, I could probably get it down to 900 (but I'd start to hear the flywheel chatter). Reading on the AEM forum some of them are getting down to 750 to 800 etc, can't believe you can have it that low & still smooth. Link to comment Share on other sites More sharing options...
Alex Posted June 27, 2007 Share Posted June 27, 2007 Its the cams that make the idle lumpy, but that in itself isn't a bad thing Getting a smooth idle down to 800rpm should be possible if your cams arn't wild. Link to comment Share on other sites More sharing options...
grahamc Posted June 27, 2007 Share Posted June 27, 2007 what cams are you running?? the hks 264 and down shouldnt change your idle. Its only 272 and upwards Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 I'm running HKS 264's. I could get it idle at 800, but it wouldn't exactly be smooth, and the flywheel would chatter just a little too much for my liking. Just wondering if it's worth spending many more hours fine tuning it to get a smooth idle at those sort of low revs, or whether with 264's & a lightweight flywheel I'll never achieve a smooth quiet idle at 800. Link to comment Share on other sites More sharing options...
Ian C Posted June 27, 2007 Share Posted June 27, 2007 I get 900-950 with the E-Manage Ultimate and it sounds much better than it did with the Blue in at 650rpm! Leave it at 1000 Easy life. -Ian Link to comment Share on other sites More sharing options...
Homer Posted June 27, 2007 Share Posted June 27, 2007 750rpm and smooth as you like Thats with a PowerFC, but stock bottom end and head and none of this lightweight nonsesne Link to comment Share on other sites More sharing options...
tooquicktostop Posted June 27, 2007 Share Posted June 27, 2007 850 rpm with 264 cams and AEM , well it did anyway Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Might have a crack at getting it to 900 with smooth idle & no clutch noise, but if I can't I'll just go with Ians easy life approach At least I know I'm somewhere near, I though you all might come back and say 'yeah I can idle smoothly all day long at 750 rpm with cams'. Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 850 rpm with 264 cams and AEM , well it did anyway Tooquick, what sort of flywheel did you have in, did it make much noise even though you had a steady idle. TBH it's more clutch noise than anything else which is putting me off idling under 1000 rpm. Link to comment Share on other sites More sharing options...
Kopite Posted June 27, 2007 Share Posted June 27, 2007 Mine's 1000rpm but it wobbles by 50rpm because of a dodgy sensor Link to comment Share on other sites More sharing options...
Ryan.G Posted June 27, 2007 Share Posted June 27, 2007 Jay have a slight play with the ignition timing when you are around 800rpm to get it smoother. Hard to say which way to go depending on your afr but normally want to advance it slightly this will get it to idle smoother. I can balance a 50p on my rocker cover at idle But on high power builds like yours i always tend to run the idle abit higher on Hot to keep the oil pressure up Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Cheers for the tips Ryan, I'm trying not to touch the fuel/ignition maps yet as Dan is in the middle of mapping it (I'm just playing with the idle maps at the mo), when Dan's happy with his stuff I'll probably start tweaking the fuel/timing around the idle area. Am I correct in assuming the fuel/ignition cells around the idle area should be pretty similar to prevent hunting? I've also not got my AFR plumbed into the AEM yet so can't log any AFR's but Michel is doing that this week (so for now I'm limited to just keeping an eye on the O2 gauge). Might take your advice on the oil pressure situation, it was starting to drop the lower my target idle was, but at 1000 rpm it was a solid 4 BAR. That's prolly reason enough to leave as is Link to comment Share on other sites More sharing options...
tooquicktostop Posted June 27, 2007 Share Posted June 27, 2007 Tooquick, what sort of flywheel did you have in, did it make much noise even though you had a steady idle. TBH it's more clutch noise than anything else which is putting me off idling under 1000 rpm. RPS street strip clutch and standard fly, no noise from this set up Link to comment Share on other sites More sharing options...
Ryan.G Posted June 27, 2007 Share Posted June 27, 2007 Does dan not do tweaking to idle and off boost then or does he just do WOT tuning Link to comment Share on other sites More sharing options...
tooquicktostop Posted June 27, 2007 Share Posted June 27, 2007 Does dan not do tweaking to idle and off boost then or does he just do WOT tuning He does set the idle during mapping Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Onto a slightly related question then, how stable is your idle, is it possible to keep it to the target exactly (ie varying 5 rpm or so) or is it impossible to keep the idle that accurate and a 50 rpm variance is more the norm Sorry for all these idle questions, but it's so interesting playing with the AEM (never had a chance to do this before), seeing the results of tweaking the settings to get a car behaving like stock is very satisfying Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Does dan not do tweaking to idle and off boost then or does he just do WOT tuning As my tuning session was broken in 2 he put some effort into getting it idling nicely & some WOT tuning, no doubt he'll do the same on the second session (getting the idle even better). TBH I'd rather he spent all his time on WOT leaving the time consuming & mundane (to him) job of cold start & idle to me Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 RPS street strip clutch and standard fly, no noise from this set up Cheers, I've got the RPS segmented flywheel which I suspect is the culprit behind most of the noise Link to comment Share on other sites More sharing options...
Jake Posted June 27, 2007 Share Posted June 27, 2007 Mines idling at about 800rpm (Motec ECU, OSG twin plate and light weight flywheel, HKS 264 cams, built engine) ....but when I start it from hot the idle is all over the place for the first 10-20seconds. AFRs are wandering about between 15 and 17 at tickover. After say 30secs or so it settles down fine but before that it's prone to stalling. - - - - - Edit to add: This has only been an issue since I changed the exhaust. I guess the mapping wants tweaking to allow for the different restriction of the new zorst. Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Cheers for that Jake, your setup is very similar to mine, do you get much flywheel noise @ 800 rpm when idling? Link to comment Share on other sites More sharing options...
Ian C Posted June 27, 2007 Share Posted June 27, 2007 Onto a slightly related question then, how stable is your idle, is it possible to keep it to the target exactly (ie varying 5 rpm or so) or is it impossible to keep the idle that accurate and a 50 rpm variance is more the norm Sorry for all these idle questions, but it's so interesting playing with the AEM (never had a chance to do this before), seeing the results of tweaking the settings to get a car behaving like stock is very satisfying I find a 50rpm variance is normal on piggybacks and even to a point the stock ECU. The gauge doesn't show it but datalogging does. Probably an emissions/self learning adjustment thang. You getting her mapped to 1.8bar then -Ian Link to comment Share on other sites More sharing options...
Jake Posted June 27, 2007 Share Posted June 27, 2007 Cheers for that Jake, your setup is very similar to mine, do you get much flywheel noise @ 800 rpm when idling? Yep. Sounds like a bag of spanners. Sounds even worse as the engine dies when you turn it off. Fact of life though mate with lightened flywheels. I wouldn't have another one TBH. Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 I find a 50rpm variance is normal on piggybacks and even to a point the stock ECU. The gauge doesn't show it but datalogging does. Probably an emissions/self learning adjustment thang. You getting her mapped to 1.8bar then -Ian That's good, I'm prolly not too far away now, I reckon I can get it to a pretty stable 50 rpm variance. Yeah getting mapped Friday, TBH boost wise we'll only go as far as is safe, if I can run 1.6 with a good safety margin that's better than running 1.8 on the ragged edge, it'll all be played by ear on the day between Dan, Michel & me, but I'm being told 1.6 should be no problem. Link to comment Share on other sites More sharing options...
jevansio Posted June 27, 2007 Author Share Posted June 27, 2007 Yep. Sounds like a bag of spanners. Sounds even worse as the engine dies when you turn it off. Fact of life though mate with lightened flywheels. I wouldn't have another one TBH. Cheers Jake, mine sounds like that too at 800, although at 1000 the noise has all but gone Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 27, 2007 Share Posted June 27, 2007 I am an old fart and a pedant, but it bugs the hell out of me! It's GEARBOX noise that you are hearing, the geartrain is being excited by harmonics the aftermarket lighter weight flywheel is failing to dampen Link to comment Share on other sites More sharing options...
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