Scott Posted February 20, 2010 Share Posted February 20, 2010 Firstly I apologise if this information is readily available. I haven't been able to find anything concrete. What are the SWL with regards to the Supra? What readings should I be seeing etc? AFR's What should I be seeing at idle What should I be seeing at Cruise What should I be seeing on WOT at varying times through the rev range. EGT's What is considered the maximum safe limit. Do the limits change for Stock/BPU/Single etc? Thats all I have at the moment. Any information, including anything I haven't asked, would be greatly appreciated. Thanks Quote Link to comment Share on other sites More sharing options...
Gaz6002 Posted February 20, 2010 Share Posted February 20, 2010 The reason you haven't seen anything concrete is because both parameters vary depending on type of mods and the location of sensors... I'd suggest a read of this book Quote Link to comment Share on other sites More sharing options...
Scott Posted February 20, 2010 Author Share Posted February 20, 2010 Seriously? Why does everyone recommend these gauges if noone can understand them, other than a select few that have studied it? Surely the AFR & EGT safety limits should be the same regardless of tune? Will that book tell me the safety limits of a TT in BPU state with an EGT & AFR probe in the 1st downpipe? Quote Link to comment Share on other sites More sharing options...
johnny g Posted February 20, 2010 Share Posted February 20, 2010 Firstly I apologise if this information is readily available. I haven't been able to find anything concrete. What are the SWL with regards to the Supra? What readings should I be seeing etc? AFR's What should I be seeing at idle What should I be seeing at Cruise What should I be seeing on WOT at varying times through the rev range. EGT's What is considered the maximum safe limit. Do the limits change for Stock/BPU/Single etc? Thats all I have at the moment. Any information, including anything I haven't asked, would be greatly appreciated. Thanks AFR: Idle - as close to 14.7 as possible Cruise - around 13.5-14.7 wouldn't be catastrophic WOT - about 11.8 is deal. Anything lower than 11 is too rich IMO EGT's - depends where you're measuring them really, but anything less than 850-900 degrees Celsius I guess? Quote Link to comment Share on other sites More sharing options...
Scott Posted February 20, 2010 Author Share Posted February 20, 2010 AFR: Idle - as close to 14.7 as possible Cruise - around 13.5-14.7 wouldn't be catastrophic WOT - about 11.8 is deal. Anything lower than 11 is too rich IMO EGT's - depends where you're measuring them really, but anything less than 850-900 degrees Celsius I guess? Exactly what I was looking for, thanks. My EGT reads in fahrenheit but that is easy enough for me to convert. Will the WOT reading change throughout the rev range or will it be pretty much the same? I read that it should go to 11ish on BPU with a stock ECU due to it dumping fuel, that was when the 2nd tubby was on full boost though. Thanks. Quote Link to comment Share on other sites More sharing options...
Wez Posted February 20, 2010 Share Posted February 20, 2010 Stock motors do run a tad rich, some go very rich Your WOT AFR should change throughout the rev range depending on how the car is mapped, what turbo is use etc etc etc etc, as already mentioned there are lots of variables but the numbers above are a good baseline. Quote Link to comment Share on other sites More sharing options...
Scott Posted February 20, 2010 Author Share Posted February 20, 2010 Stock motors do run a tad rich, some go very rich Your WOT AFR should change throughout the rev range depending on how the car is mapped, what turbo is use etc etc etc etc, as already mentioned there are lots of variables but the numbers above are a good baseline. The main reason I ask is I have a Mines ECU and I just want to keep tabs on things. I know there will be safe AFR margins through the rev range, just looking for what is unsafe. Surely regardless of the tune, turbo etc etc etc the dangerous AFR readings will remain constant? IE 8.0 is far too rich regardless of what variant of aspiration you are using and 20 is far too lean? Quote Link to comment Share on other sites More sharing options...
johnny g Posted February 20, 2010 Share Posted February 20, 2010 The main reason I ask is I have a Mines ECU and I just want to keep tabs on things. I know there will be safe AFR margins through the rev range, just looking for what is unsafe. Surely regardless of the tune, turbo etc etc etc the dangerous AFR readings will remain constant? IE 8.0 is far too rich regardless of what variant of aspiration you are using and 20 is far too lean? That's true, but you can det due to a bad tune - however, on BPU with stock(ish) ECU, that shouldn't happen Quote Link to comment Share on other sites More sharing options...
Scott Posted February 20, 2010 Author Share Posted February 20, 2010 This is what I have at the moment Cold start idle 11-12 Once warm 14.5ish Cruising 13.5-14.5 WOT pre 4k RPM 12.5-13.5 depending on revs I haven't tried post 4k as I don't have a restrictor ring in place at the moment. That sound about right for now? As you say as long as nothing is miles out I would think everything is OK due to it being stockish. I now know approx what I am looking for rather than unknown numbers on a gauge though Quote Link to comment Share on other sites More sharing options...
Wez Posted February 20, 2010 Share Posted February 20, 2010 Surely regardless of the tune, turbo etc etc etc the dangerous AFR readings will remain constant? IE 8.0 is far too rich regardless of what variant of aspiration you are using and 20 is far too lean? Yes and no. If you take the extremes like you mention then yes that statement is true, but when you start fine tuning then no it isn't. As a very simple example one setup could run 13AFR around 3000rpm at 0.25bar boost but another setup might require 12AFR. Quote Link to comment Share on other sites More sharing options...
Wez Posted February 20, 2010 Share Posted February 20, 2010 This is what I have at the moment Cold start idle 11-12 Once warm 14.5ish Cruising 13.5-14.5 WOT pre 4k RPM 12.5-13.5 depending on revs I haven't tried post 4k as I don't have a restrictor ring in place at the moment. That sound about right for now? As you say as long as nothing is miles out I would think everything is OK due to it being stockish. I now know approx what I am looking for rather than unknown numbers on a gauge though I imagine it will go richer further up the rev range, there is also a lean spot around stock turbo change over, not sure if the mines maps that out, its also possible yours will run leaner, another perk of the mines setup. Quote Link to comment Share on other sites More sharing options...
Mcgoo Posted February 20, 2010 Share Posted February 20, 2010 This is what I have at the moment Cold start idle 11-12 Once warm 14.5ish Cruising 13.5-14.5 WOT pre 4k RPM 12.5-13.5 depending on revs I haven't tried post 4k as I don't have a restrictor ring in place at the moment. That sound about right for now? As you say as long as nothing is miles out I would think everything is OK due to it being stockish. I now know approx what I am looking for rather than unknown numbers on a gauge though Is your WOT not a tad lean as on the transition to tubby 2 it will get a bit leaner still. I would have thought 12.5 on WOT would be max ? Quote Link to comment Share on other sites More sharing options...
colsoop Posted February 21, 2010 Share Posted February 21, 2010 I posted about this quite a while back. The linked thread were my readings if it helps at all: http://www.mkivsupra.net/vbb/showthread.php?t=142146&highlight=AFR Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 21, 2010 Share Posted February 21, 2010 AFR (wideband) std and single turbo, (dependant on ECU and mapping) start up/warm up-10-12 warm idle-will vary due to std lambda switching-13.9-14.9 cruse-13.0-14-9, but you will see up to 17.9 -20.9 on closed throttle. WOT-on boost you don't want to see anything more than 11.8, 11.4 being safer, but you can see 10.0 sometimes. EGT (an accurate one in turbo housing or before) and it will vary a lot depending on state of tune and cam timing. idle will be anything from 150c-300c hot cruse 350-600c WOT on boost 750-900c if you're seeing 950c or more then you need to do something about it. Quote Link to comment Share on other sites More sharing options...
Scott Posted February 21, 2010 Author Share Posted February 21, 2010 Thanks guys Quote Link to comment Share on other sites More sharing options...
monsween Posted February 21, 2010 Share Posted February 21, 2010 AFR (wideband) std and single turbo, (dependant on ECU and mapping) start up/warm up-10-12 warm idle-will vary due to std lambda switching-13.9-14.9 cruse-13.0-14-9, but you will see up to 17.9 -20.9 on closed throttle. WOT-on boost you don't want to see anything more than 11.8, 11.4 being safer, but you can see 10.0 sometimes. I was told those figures too. Altho the only difference was AFR on WOT between 11.2 and 11.4 was perfect Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted February 21, 2010 Share Posted February 21, 2010 i have cold start 12 warm idle 15.5 cruse 14.5-15.5 wot on boost 10.6- 11.2 ( i see this as a safe mix as im am not a pro mapper) Quote Link to comment Share on other sites More sharing options...
JamieP Posted March 18, 2010 Share Posted March 18, 2010 (edited) I just googled "EGT's on cruise" and it took me to this thread, my egts seem pretty high to me, on cruise at say 90mph they read a constant 800c, peak at about 860c at 100mph off boost, soon as i touch the throttle they do go down a bit. At them temps should the manifold not be glowing? maybe dodgy sensor? its always been like this from when i first went single. A full wot through the gears run i see about the same egts, 850-870c at 2bar. what are others seeing at 90mph on cruise? Edited March 18, 2010 by JamieP (see edit history) Quote Link to comment Share on other sites More sharing options...
Scott Posted March 18, 2010 Author Share Posted March 18, 2010 Cruising I see 900-1000 farenheit.... are you talking celcius? Quote Link to comment Share on other sites More sharing options...
JamieP Posted March 18, 2010 Share Posted March 18, 2010 Sorry, yes celcius. edited above. One other thing is the sensor seems to read right before the car is started, checked it before i started today and read 15c about lunch time. Quote Link to comment Share on other sites More sharing options...
Wez Posted March 18, 2010 Share Posted March 18, 2010 Sorry, yes celcius. edited above. One other thing is the sensor seems to read right before the car is started, checked it before i started today and read 15c about lunch time. What is the AFR at cruise, where is the sensor mounted and what a/r exhaust housing is on the turbo? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted March 18, 2010 Share Posted March 18, 2010 Have a chat to Ryan, he will give you the answer;) Quote Link to comment Share on other sites More sharing options...
dandan Posted April 5, 2010 Share Posted April 5, 2010 (edited) what are others seeing at 90mph on cruise? At a 90mph cruise in 6th I am seeing no higher than 720C. 14.6-14.8AFR closed loop 0.81 housing on 67DBB 3 row intercooler This is from Defi thermocouple probe in rear runner of exhaust manifold Solaris probe is in front runner ( I could interrogate that for additional temps if you want?) Cast manifold (all exhaust parts are ceramic coated) Edited April 5, 2010 by dandan (see edit history) Quote Link to comment Share on other sites More sharing options...
Scott Posted April 5, 2010 Author Share Posted April 5, 2010 I'm seeing 600 in the 1st de-cat which will probably be the same as yourself Dandan, I read that you subtract approx 100 degrees from headers to decat. Quote Link to comment Share on other sites More sharing options...
Terminator Posted April 5, 2010 Share Posted April 5, 2010 I have my EGT sensor in about 40mm from the exhaust manifold flange in number 6 and see 720C 760C at WOT with my GT74, very occasionally get 800C. Quote Link to comment Share on other sites More sharing options...
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