Guest bastaad525 Posted July 7, 2003 Share Posted July 7, 2003 Which brands are known to be accurate? I'm thinking of going autometer since I already have two fo their gauges in my car, and they have a Phantom air/fuel gauge for like $50 which is way less than I thought they'd be. Anyone use these and know how accurate they are? Any other brands proven to work well for the same price range? And lastly, do these gauges just hook up to the O2 sensor? I'm assuming you have to split the sensors wire, and hook the split up to the gauge? Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 7, 2003 Share Posted July 7, 2003 No 1,2,3 or 4 wire Narrow band O2 sensor based A/F meter is going to be accurate regardless of brand name. The problem is in the type of O2 sensor used in these meters. The narrow band O2 is only accurate at Stoich. Anywhere else and it's a guess as to how rich or lean you really are. If you're serious about using it to tune your car, then only consider a UEGO Wide Band based meter. If you're only looking for the cute little LED display , then it doesn't matter which one you buy. Get the one that looks the best to you. If you're looking for a good relatively cheep WB O2 meter, then check out the OZ-DIY-O2 unit from Tech Edge. I have the Version 1.5 unit now and will soon go up to the 2.0 unit. The 2.0 will support more then one type of sensor and has many other fetures like data loging. The other two units only support the L1H1 NTK sensor and it's a little pricey and can get a little hard to find at times. You have a choice of buying a pre made unit or building it yourself. It all depends on your soldering skills and ability to follow assembly instructions. Here is a link to their web site: http://www.techedge.com.au/vehicle/wbo2/default.htm It's more expensive then the Autometer, but think what you're using it for in the first place. A wide band O2 meter is the ONLY type of O2 meter to use for tuning purposes. Anything else is just pure junk IMHO. Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted July 7, 2003 Share Posted July 7, 2003 Get an EGT gauge and use it to tune with. Autometer makes it in Phantom aswell. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted July 8, 2003 Share Posted July 8, 2003 Kewl that sounds like a good idea then, if the air fuel ones aren't so great. How much for an EGT gauge? I assume about the same, for the gauge, but where does it get its signal from? I'm assuming nothing stock on the car.... so how much am I looking at for the whole setup, including whatever sensor I need to read the temps? Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted July 8, 2003 Share Posted July 8, 2003 They are about 130.00 for the gauge and the sending unit. Much more costly then the A/F ratio gauge but, this one actually give you real information. Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 8, 2003 Share Posted July 8, 2003 Cody, So how about some tips on how to tune a car using an EGT Meter? What are you shooting for? How do you know what temperature is right at what load setting? Air Fuel meters I've always understood, but EGT's were some what of a mystery as to how the temperatures relate to operating conditions. Thanks for any info. in advance. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted July 8, 2003 Share Posted July 8, 2003 $130 is still not bad, compared to the wideband O2 setup, and considering it will save me money from having to always go to a dyno to tune.... that's the thing, I just need some reliable way to tune my car w/o always spending $$$$ at a dyno, and I KNOW there are ways to do this. Okay so, EGT it is then. Anyone have a certain brand/make/model of EGT setup they know to be particularly reliable? Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted July 8, 2003 Share Posted July 8, 2003 I use the Autometer brand EGT that you can get from Summit, Jegs or wherever. As far as tuning you would want to shoot for about 900* when around town, 1200* to 1300* on the highway cruising. Max power is developed at about 1500* to 1550*. The longer your in boost and on the gas the higher the temps will get. I shoot for about 1550* at the end of 4th gear on a full run. I've been told that hitting 1600* is ok but, don't go over that. These temps are with the probe installed before the turbo in the collector. Something to consider is that timing will effect your temps as well A/F ratio. Retarded timing will be increased temps and advance timing will lower temps. Since every car is different then you just need to get as close to stock as possible and then start playing with it from there. Document as much as possible if you have the ability to make several changes like with a aftermarket F.I. Ofcourse a session on a dyno with a wideband O2 and the EGT would be a good way to know for sure where your at with your A/F ratios and power levels. Small changes in boost levels can bring big changes in temps when using a large tubo or one that is out of it's effency range. It's always tempting to increase the boost some but, that can lead to bad things if your not careful. Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 8, 2003 Share Posted July 8, 2003 With all the temperature variations that you're talking about (timing changes, probe location, engine type) how do you tune a car from a base map to final tune without using a WB O2 meter? I've been told that an EGT is great for monitoring once you've got a working baseline on what temps. correspond to what A/F ratios and the engine tune is fairly close to final. I still don't see how an EGT can replace a WB O2 for your initial tuning phase on an unknown engine from baseline. I didn't think that the factory temps had much meaning once you've modified the heck out of the engine. I have also never seen a dyno shop tune a car by using only an EGT meter from the start. They all seem to use a WB A/F meter exclusively. I'm not trying to argue, but I am trying to better understand how the tuning process would work by using only an EGT. What A/F ratio does 1550* correspond to? Do all engines get max power at 1550*? Can some others, with experience in tuning, chime in and give their take on what's the best tuning method and what tools to use? I know we've got some very experienced people here and tuning has always been such a black art. Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted July 8, 2003 Share Posted July 8, 2003 I don't think that you can make a direct coralation between an exact A/F ratio and a degree of tempature. The temp would be different for every car. Some cars will better at regecting more heat and some will absorb more heat. The information that I gave should only be used as a guide. I tried to state that in my post but, maybe I was not clear enough about it. An EGT is a tuning tool not the absolute answer to tuning your car. If you do not have a Dyno with a wide band or can't afford to sit on the dyno and have the work done it is a good tool to use when making changes. I'm not trying to say that an EGT gauge is a replacement for a wideband O2 only that the $50 A/F ratio gauges are not very accurate when used with a simple O2 sensor and that a EGT is a better guide as to what is going on with a setup. Another good thing is still the tried and true method of reading your plugs after a hard run. I agree with you that we have members of the board that have spent the time and money on Dyno time but, I never seem to get to much of an exact answer when I see this question posted. I think that is because there is no exact answer for this situation. I'm sure someone here can post better or more accurate temps then what I have givin but, these are what has worked well for me and some others that I know. Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted July 9, 2003 Share Posted July 9, 2003 No way can you use EGT alone to really tune a car - only if you're working with an OEM ECU that has a set spark curve could you do this by comparing with others. For instance - I can run a PIG rich A/F and retarded timing and get sky high EGT. Just looking at the EGT how would you know what was going on? Some would tell me I was lean EGT work best in conjunction with a W/B O2 IMO. This way you can see your TRUE A/F and use the EGT to evaluate timing. Also - most EGT are fairly slow. I've tuned with an RTD type sensor that was incredibly fast but it didn't have a gauge, had to be read by my EMS, and the danged thing died on me. $149 shot! I use an Apexi EGT with P/H and warning just to keep an eye on things but with their track record I'd never mount it in front of a turbo since when it fails it takes the turbo with it As for what W/B works best be aware that the current Techedge offerings only use a VERY expensive NTK sensor that has recently become RARE. Replacements from Honda are $300! Soon Honda may be the ONLY source for these AEM makes a Bosch based W/B that rox however it currently has NO display and is designed to be attached to an aftermarket EMS. Techedge V2 is supposed to use a Bosch style sensor but I don't think it's been released yet. Lots of W/B info on the AEM EMS support forums.... Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 9, 2003 Share Posted July 9, 2003 Thanks Cody for the information that you've provided. I wish more would be willing to address the tuning side of things. Everyone seems to be so hung up on the mechanicals of building up a supper high HP engine, but completely ignore the tuning side of things. The best parts don't help if you can't get it tuned right and a turbo engine requires even more care in order to keep it alive. I agree that an EGT is a useful tool and, if used properly, can aid in the tuning process. I also agree that any common NB O2 meter is not up to the task of tuning a car. I would, however, like to see more people look into the possibility of using a Do It Yourself Wide Band O2 kit to do the tuning with. If you have the soldering skills to assemble the kit, it is not that cost prohibitive or difficult. I feel that about $250 could get you into a tool that does more then a EGT or NB O2 could ever think of. You don't need a dyno to tune a car, but you do need to know where the car is running in order to know what to change. A Lambda meter does just that. So many people are caught up in the "ricer" gadget craze and don't think of what the purpose of a gauge is for in the first place. I've used a Tech Edge WB O2 meter now for more then a year with fantastic results. The cost of a WB O2 meter may seem high, but so do Craftsman tools compared to the ones made in Taiwan. Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 9, 2003 Share Posted July 9, 2003 BLKMGK, I think the V2.0 Prebuilt units are going to be released today or tomorrow. The kit form should be available soon after. The NTK sensor can still be found on eBay for about $190. The Bocsh sensor used in the V2.0 unit should be a little cheaper and more readily available. I like the data logging features that go along with the O2 readings. The ability to read A/F ratio, RPM, TPS and any number of other readings, and log them in real time, is the key to easy trouble shooting. Bottom line... Use the right tool for the right job. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted July 9, 2003 Share Posted July 9, 2003 whoa whoa I'm NOT getting either the a/f meter or the EGT sensor because I'm caught up in any craze. I"m trying to do the most I can to get the most performance possible out of my turbo engine w/o spending a fortune on dyno time, w/o spending a fortune on expensive parts like that do it yourself kit, which is still very expensive even for the DIY version, and w/o risking blowing up my engine. Now, I do understand completely that without spending time on a dyno (which I DO plan to do at some point) or using more sophiscated tools like that DIY five band sensor, that I will not be able to get the 100% best performance out of my turbo engine nor will it be tuned 'right'. The same could be said of even sticking with the stock EFI components or other stock parts.... I know there's 100 things I can do to make the car run better and safer, but $$$$ is the issue. I want something like a reasonably priced EGT or A/F sensor, more than any other reason, because I just want to be sure that I am well within the margin of safety for my setup. 100% perfect tuning and performance can come later, but I at least want to have a little fun, raise the boost a bit, and know without a doubt that I wont blow up my engine. As far as issues like with the EGT, and how timing can affect things like that readout, or where to start from as your 'baseline', the solution for me is simple, though also not perfect. My solution is just to follow in the steps of others. If X number of guys have very similiar if not identical setups to me (and I try to mimic them as closely as possible) and they have done well with X degrees of timing, or X pounds of fuel pressure, and they have tried this or that out on a dyno so they know for sure, then I use that as a starting point. I know every car is different but most turbo Z's I would think, are not so drastically different that two near identical setups would need drastically different timing to run well, for example. I've used this method with my Z for years now, coming to this board or the Zcar.com forum, and just asking "hey how is YOUR car set up?". Usually if I follow in those steps I end up with a very good running car. From there, a tool like the EGT sensor, I think, WOULD be a good tool to at least let me know, with those 'baseline' settings, and also with any changes made after that, if I'm running in my safety margin. If I'm wrong here please let me know and save my $100-200-who knows how many hundreds of dollars. I just want to be safe and have a reliable daily driver, I'm not looking for the end all be all way to fine tune every last minutae on this car right now, but I want to get as much power out of it as possible and have a fun car too, and not have to spend a fortune to do it, at least not all at once. Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted July 9, 2003 Share Posted July 9, 2003 Thanks Cody for the information that you've provided. I wish more would be willing to address the tuning side of things. Everyone seems to be so hung up on the mechanicals of building up a supper high HP engine, but completely ignore the tuning side of things. The best parts don't help if you can't get it tuned right and a turbo engine requires even more care in order to keep it alive. I agree with you about the hardparts of the motors being the most focused on here as well as with many set-ups. I've certainly been guilty of that myself many times. Seems like if you ask what a good combination for a turbo car is for "this" much money then you'll get 10 differnt replys that all are good answers. As for the tuning I think that the lack of adjustablitlity with the stock setup is one reason for only a few answers. Really there are not all that many guys that have aftermarket computers or experience in a shop to provide real answers. I recently changed computers in my car and still can't believe the total differnce of the before and after aspects of the car. So much more power and so much better drivablity. The computer really brought all the hardparts together just as I had hoped it would. I'm sure that another system that is user tunable could be even better optimsed if I had the time, money and knowledge to do so. Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 9, 2003 Share Posted July 9, 2003 Then so be it. I believe you've answered your own question. If I'm not mistaken, you originally asked: Which brands are known to be accurate? Well, you get what you pay for. Much of what you're looking for depends on how modified your engine is. If you use the same formula as someone else with a slightly modified engine, then the results will probably turn out OK. The closer to the edge you get, the less margin you have for error. If you're only boosting to like 10PSI with the stock system, then most anything will work. If you're pushing 20+PSI with big injectors, adjustable FPR and a programmable ECU, then forget it. It costs to go fast... How fast can you afford to go? Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted July 9, 2003 Share Posted July 9, 2003 heheh I understand.... speed = $$$ And yeah I'm only gonna be doing 10psi, on a pretty much stock setup with stock EFI, and most people say this is actually fine on the stock EFI and wont lean out, but a few guys who have dynoed, running 10psi on mostly stock setups, have reported that though there was no ping, the mixture above 4000-5000 RPM would run way lean. I just want a way to know for myself on my particular setup if this happens, w/o spending a fortune. I'm not even looking for how much of a lean condition, I just want to know if it's lean at all, so that I know either a)I need to get more fuel in there or b)I need to let off the boost a bit. ANYTHING to not blow this engine up! So would a regular A/F gauge or EGT sensor be able to at least tell me this much? Of the A/F gauges I've seen, the one that catches my eye the most is the one Dawes makes: http://www.dawesdevices.com/airfuelmeter.html Not sure if any of you guys have tried this one.... notice it's not flashy or ricey looking by the way I've heard great things about their boost controllers and they're quality and service overall, but again, if it really will not be able to tell me anything I wouldn't spend the money. I do appreciate your input jt240z, if I had the money I'd probably get a five band just based on your first post to this thread, and because of that advice I have not as of yet ordered an A/F or EGT meter. Just trying to get more info here. And yes my original question WAS answered but of course that just gave rise to new questions, the question now being, though they are not accurate would ANY of these lower cost units (A/F or EGT) serve the purpose of warning me if I'm running lean AT ALL, even if not accurate in the way of HOW lean? Just enough to let me know I'm safe at the boost I'm running? Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted July 9, 2003 Share Posted July 9, 2003 I dont know if this makes a difference or if it goes w/o saying, but I'm really only concerned with mixture at WOT, so I only need something that will be accurate at that point. About that Dawes.... I'm not sure if it would apply differently to the O2 sensor in our cars, but the thing sure sounds like it would be at least somewhat accurate. They explain pretty clearly how it reads of the O2's voltage..... why wouldn't that be accurate? Quote Link to comment Share on other sites More sharing options...
Nigel Posted July 9, 2003 Share Posted July 9, 2003 Hey Bastaad... I sympathize with what you're going through. I've never tuned an engine before in my life (running SDS EM3-6F), and it's very hard to get definitive answers as to how to go about it. As for EGT vs. NB A/F Ratio, I have both, and as a novice, I find myself looking at the A/F gauge the most. At the very least, it tells you if you're rich, lean, or somewhere in the middle, and it tells you instantly. With the EGT guage, a lot of interpretation is required. Temperatures go down as the mixture gets richer OR leaner. So, how do you know which side you're on? Furthermore, depending on the quality of the probe (which you may have to buy separately) there is a delay in the response time. I went with the Autometer Competition probe. That's their mid-priced probe. From memory, I think it was $100 for the probe and $100 for the guage. Placement also makes a difference, but before the turbo is the best idea. Anyway, I've been driving the car for a couple of months, and I'm jsut starting to try to figure out what kind of usefull information I can get from the EGT guage. I've noted that I get temps of around 1200 to 1300 cruising at 75 MPH. Idle is around 800+ if I've been driving for a bit. At full throttle it peaks at 1400. I've been told that 1400 is the max I should want to see, but others have said 1500+. Regarding A/F guage accuracy, there are two primary problems. One is that the output of the 02 sensor is very non-linear. The output goes almost from one extreem to the other around stoich, and has very little change at richer or leaner mixtures. So, it's very difficult to tell if you're at say a 13:1 or a 10:1 A/F ratio. The second problem is that the output is very much affected by the temperature of the probe. What makes wide band sensors so effective is that they are temperature compensated. Nigel '73 240ZT Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted July 9, 2003 Share Posted July 9, 2003 Couple of things - narrow band sensors can tell you rich or lean over and below stoich. That means rich might be 13:1 or it might be 9:1 - one of those melts pistons in my motor the other blows raw burning fuel out melting my turbo. Hell rich could even be 14:1 with the response curve those suckers have - they flip like a lightswitch. That's why in closed loop operation the Autometer gauge looks like a disco ball as the sensor flips richlean as the ECU compensates. Techedge - I've yet to see those suckers tested against another meter by an independant 3rd party. They were challenged on the AEM board but the guy doing the testing has never heard back from them on an eval unit and refuses to purchase one himself just to prove a point. If you're building it yourself you may also run into issues where one unit is more accurate than another - yes even with free air calibration. Currently someone I know is testing Horiba, NTK, FJO, Motec, and AEM W/B against one another under real world circumstances. I hope to know soon how close they all came to one another but I won't be surprised to find as much as a half point or more difference in some of them. Techedge isn't in this test for the reasons stated above. I've also heard at least one other person cast some doubt on the Techedge and this was a guy with access to test gas and measuring equipment however he refused to publish his complete findings The Techedge makes me nervous frankly, if it's off how would you know exactly? Is it really worth risking a motor over say $300? I wish Techedge had sent an eval unit to this guy to compare against the other main ones out there! If nothing they have provided low cost competition. I'm pretty much on the fence concerning these meters but don't think I'll trust an expensive motor of mine to one of them. Yes, today you can still manage to find NTK sensors at "reasonable" prices, that will slowly peter out as the remaining supply goes away. I happen to have 2 spare sensors not counting the one in the car but will go Bosch for my next W/B install. I paid nowhere near $190 for these spares! The Bosch sensor AEM is using is supposedly a pretty new one and only costs $30 to replace I'm told. NTK can bite me and so can Honda @ $300 apiece! Porsche, Subaru, and others supposedly use these Bosch sensors so no way will these go away so easily Quote Link to comment Share on other sites More sharing options...
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