myplasticegg Posted December 3, 2006 Share Posted December 3, 2006 When tuning SU's would it be better to have an EGT gauge, narrow band o2 or wide band o2? I plan on having two of whatever sensor I end up going with, on for cylinder two and one for cylinder five. This will be going on a worked L28 w/ flat tops, ported E88 head, big cam, Stahl header, N36 intake, and early ZX 5 speed. I am not sure about using the EGT, having two of them might be hard to keep an eye on when at WOT. NB O2 is nothing more then a blinking light telling you you're "close" WB O2 is good, but costly. Would allow for datalogging through a laptop that I already own. I am looking for some insight on this one, this is my first N/A build and I plan on keeping it for years to come. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted December 4, 2006 Share Posted December 4, 2006 WBo2 would be best...but they are pricey... Most people don't use any sensors to turn their SUs. Just a manual AFM that you hold over the open carb. Quote Link to comment Share on other sites More sharing options...
ktm Posted December 4, 2006 Share Posted December 4, 2006 olderthanme, people use Colortune to get the fuel mixture correct. The synchrometer lets you balance the air flow; the O2 sensors should tell you your A/F mixture like the Colortune, correct? Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted December 4, 2006 Share Posted December 4, 2006 You can use one of those clear sparkplugs (are they called colortune?). and tune until you get a blue flame. I don't remember the band name but I read about them a while back. Quote Link to comment Share on other sites More sharing options...
katman Posted December 4, 2006 Share Posted December 4, 2006 WBO2. Then prepare to join the "carbs are just a semi-metered fuel leak" crowd. Quote Link to comment Share on other sites More sharing options...
myplasticegg Posted December 4, 2006 Author Share Posted December 4, 2006 as long as it leaks kind of close each time i fire it up, i'm cool with it. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 4, 2006 Share Posted December 4, 2006 I've had good luck with NB, but I'm tired of fighting this fight. You can search narrowband O2 and find one of the many previous threads where I've said what I did, how much it cost (less than $40) and how it compares to WB in the experience of a couple friends of mine. Quote Link to comment Share on other sites More sharing options...
ktm Posted December 4, 2006 Share Posted December 4, 2006 olderthanme, the clear spark plug is Colortune. You can pick up a kit from MSA for around $60. It's basically an A/F meter. Jon, I have read your experience with the O2NB, but I am unclear on how it tells you your mixture. You indicated in previous posts that you just hook up a voltmeter to the O2 sensor and take your reading from there. How do you know what the acceptable range is on the volt meter? Previous posts indicate voltage ranges from 0.8v to 0.9v. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 4, 2006 Share Posted December 4, 2006 Voltage range on a NB is from 0 to 1V. I can't remember all the values right off the top of my head, but 13.2:1 is about .8V. I think, but I'm not sure, that stoichiometric is .5V. You can find all the values online if you search. So I just tuned at WOT to hit .8V. You have to deal with the refresh rate on the display of your voltmeter, so you have to do a lot of pulls. Still, if you stick with it long enough you'll get it pretty close. I had the voltmeter in my car for a couple months, I just opened it up whenever traffic would allow and watched the meter, and pretty soon I had things dialed in a lot better. I wasn't worried about mileage or any of that. A lot of people say that a NBO2 only tells lean/rich, and I think most of them have only watched the voltage signal on a FI car at idle. They do cycle back and forth like that, because at idle FI cycles between lean and rich. On a carbed car, or at WOT on a stock FI setup the O2 doesn't cycle, it will read a consistent voltage (unless of course you have a lean or a rich spot somewhere). Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted December 5, 2006 Administrators Share Posted December 5, 2006 Jon, A NBO2 is very accurate at 14.7. It is FAR less accurate on either side of 14.7, and is exacerbated by varying temperatures. However, I believe a savvy guy can get by with a NBO2 on an NA car, just as you have done. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted December 5, 2006 Administrators Share Posted December 5, 2006 I dug out a TWM leaflet. According to them, this is the output of a typical NBO2... . Quote Link to comment Share on other sites More sharing options...
myplasticegg Posted December 5, 2006 Author Share Posted December 5, 2006 How would you handle dual NBo2? Or just run one and hope the other carb is the same? Tune one carb at a time? Are there any datalogging programs that you guys have used with NB o2's? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 5, 2006 Share Posted December 5, 2006 I dug out a TWM leaflet. According to them, this is the output of a typical NBO2.... That graph doesn't reflect my experience. Mine was an unheated, single wire Bosch O2 and it read pretty consistently after about 5 minutes warm up time. I ran it for months, so I think that I would have noticed if temps really change the output on the sensor as shown in the graph. Dual carbs, get a 3 into 2 header (Nissan Comp) and put an O2 in each collector. Quote Link to comment Share on other sites More sharing options...
myplasticegg Posted December 5, 2006 Author Share Posted December 5, 2006 The stahl header is 3 into 2 and made local (20 miles south) with AMAZING quality. They will even put the o2 bungs on there for me. Do you happen to have a link for the nissan comp header? i haven't been able to come up with anything through lots of searching! http://web.archive.org/web/20020828193907/www.buckeyetriumphs.org/technical/Carbs/AFMonitor/AFMonitor.htm This shows how to build a graphical display for the o2 gauge. I suck at figuring out circuts but i would love to narrow it down, I know not all of those values are needed. I have a Dawes Devices in my turbo minivan and it works like a charm. Much eaiser to watch colored lights then to watch numbers. http://www.3barracing.com/product_3.htm (I can remember when they were $35, and I'm only 19!) Quote Link to comment Share on other sites More sharing options...
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