datsunan Posted December 29, 2004 Share Posted December 29, 2004 I'm looking into a new fuel management system and am torn between MS and SDS. Sds does not need a pc to program supports a wb o2 and has sequential injection, it costs alot more but is it worth it? I'm looking to squeeze the most reliable power I can from my 83 turbo. I am currently using a reprogramed z31 ecu from Jim Wolf Tech but can not adjust anything for more hp. I think the wb o2 sensor is very important to maximizing hp safely but is it worth 1k$ ? Any input on any of this? Quote Link to comment Share on other sites More sharing options...
Forrest Posted December 29, 2004 Share Posted December 29, 2004 I'm not going to really get into this one, except to make one point. I PREFER the laptop, it's much easier to program. You can buy/build the little remote display (Megaview) and I believe it lets you program everything you'd want to mess with while the car is running. So if that's what you really want, you can have it with MS too. Quote Link to comment Share on other sites More sharing options...
Xander Posted December 30, 2004 Share Posted December 30, 2004 Sds does not need a pc to program supports a wb o2 and has sequential injection Not needing a pc/laptop is not a plus in my book. With the megasquirt system you can see the injection curve and therefor it is a lot easier to know what you are doing. And since when does SDS support wideband 02 and sequential injection. I though I missed something, that maybe they had a new product out. but I just visited there site and looked. SDS does not support wideband 02/ sequential injection. For the price difference you can easily buy a nice second hand laptop. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted December 30, 2004 Share Posted December 30, 2004 You can adjust your JWT ecu as well. You need an eprom burner or you can tune it while driving with a romulator from xtronics.com. You can run up to 72lb injectors, and if you want to change maf sensors that's easily done as well. A ford lightning maf will flow upto 1000 cfm. The romulator is 179.00 or so and an eprom burner can be had in a kit fo r 50 or so. Either way you should have a wideband. You can pick up several different kinds of wideband sensors for under 400.00 dollars. If you need help with the z31 ecu tuning let me know, I have some experience with those units. Bernard Quote Link to comment Share on other sites More sharing options...
datsunan Posted December 30, 2004 Author Share Posted December 30, 2004 Hey Bernardd thanks for the reply. Have you worked with MS befor? What do you think would be easier to mess around with on a regular basis. I have not done any burning/reprograming befor and do not want to have to reliey on others for help, although I appriciate your offer and may take you up on that, I'm in SD CA where are you? I like to tinker and will probably be modifiing the engine more over time so reprograming may happen often, ie after porting,new down pipe, possibly squeezing. I am only making 250rwhp and with my current mods think I should be making more, dissapointed with JWT ecu output. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted December 30, 2004 Share Posted December 30, 2004 You can program either one as many times as you want. I have a buddy with the MS ecu. He plugs in the laptop and tunes, I do the same on my car. One advantage I see to the MS is that you can see where you are in the maps while driving the car, but you can figure out where you are in the z31 ecu very easily. But you have to build, or have it built, the ecu and rewire the car. What is the problem with the jwt ecu? They will retune it as well for a fee. Either way you're going to have to know what you're doing, what the car is doing and what you want it to do. Quote Link to comment Share on other sites More sharing options...
datsunan Posted December 31, 2004 Author Share Posted December 31, 2004 Yeh that was me with the timing flutuation, it was my tps not being in the right possition when I would set the timing. my timing is good now but I have a bad idle that is driving me crazy. It misses and will drop out 100rpm every 5 sec or so. It idles perfectly smooth at start-up for about 3-5min then maybe goes into an open loop and starts missing. I just read something on the ms website that makes me think my exhaust gas temp is to low for proper o2 operation. I have no cat or mufflers on the car so my temps may be low at idle. My electric fan has also burned out the temp switch so it stays on and is probably keeping my water temp lower than it should be. Do you think I'm onto something? I've heard that the JWT system often has problems such as rough idles so that was one reason for wanting to change it and I did not know I could adjust my a/f mix. If you check my profile under my last post it lists most all of my mods. I had it dynoed at 250rwhp if JWT is telling the truth about the potential for thier system then I am at least 30hp short. I want to try and make 350rwhp and I've seen guys here making as much as me with the stock turbo. I was at 16 psi to get 250rwhp and it was running lean. I don't want to pay JWT more money every time I make some mods, I'm a do it yourself kinda guy, I did everything to my car myself but the crome and interior, right now my car is in the SD international car show so its not a POS. I have not been impressed with JWT's service. I live 15 min from them but they are unwilling to help me troubleshot my problem. After spending almost $3000 with them I think I should get some free support. No? Thanks again for any help Bernardd. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted December 31, 2004 Share Posted December 31, 2004 There are a # of changes you can make but you should first rule out the usual vac leaks, bad plugs, fuel pressure, etc etc. My experience with JWT ecu's is that they usually err strongly on the rich side (10:1 afr's) on the top end. A batronix eeprom programmer is the ticket for a cheap fix if all the mechanicals are ok. You can change the injector latency, the idle timing, afr's, the load scaler.....all kinds of parameters with the z31 ecu to get the idle where you want it. Quote Link to comment Share on other sites More sharing options...
Tony D Posted December 31, 2004 Share Posted December 31, 2004 As was said earlier, you can build the megaview, and have a four button controller to scroll through and adjust everything in the MS. MS does support WBO2 directly with anothe board you incorporate, and some of the next generation will not need this board. You only need a laptop or desktop to do initial configuration---then you can change everything from there with the megaview. What is the most efficient is DATALOGGING withthe laptop. it lets you go out, and concentrate on holding a load point (say steady speed via and brakes for an rpm, while gradually increasing throttle position) this allows you to go back and see your O2 reactions, and make adjustments accordingly afterwards instead of while driving. In reality, it only takes about three hours to get a very good map into a MS. With some of the tuning utilities and self-tweaking programs you can get REALLY CLOSE TO PERFECTION while simply driving around and datalogging! Quote Link to comment Share on other sites More sharing options...
datsunan Posted January 1, 2005 Author Share Posted January 1, 2005 Yeh I was reading on the ms website about the wb o2 but it sounded like it was still in the works.? I could not tell if it was availible yet or not, I guess it is if you buy the support board for it. I might want to wait and see if the come out with a new version that has it built in. Quote Link to comment Share on other sites More sharing options...
datsunan Posted January 1, 2005 Author Share Posted January 1, 2005 I have replaced everthing on the engine with new parts, tried 3 diff plugs, new 8mm wires,msd ign,2nd new fuel pump, I am running to much fuel press at idle (55psi) because my new aeromotive fuel pump is so big I need to upgrade my return line to get the pressures to come down. It ran the same before I change it out. I have not found any vacuum leaks and since it runs great when cold I don't think its a leak. Nothing I have done has had any affect. can I run a wb o2 on the z31 ecu? Its still a 0-5volt sig right? I would like to try and use a heated o2 and see if maybe the problem is that its to cold, do you know if I can? Ben at JWT seemed adament about using the stock o2 sensor for that ecu. You say I will need the burner and a couple of chips, do I need to replace the chip every time I make changes or can it be reburned? I have never done something like that so I'm kinda in the dark on how the programing happens. Thanks Paul Quote Link to comment Share on other sites More sharing options...
TimZ Posted January 2, 2005 Share Posted January 2, 2005 It misses and will drop out 100rpm every 5 sec or so. It idles perfectly smooth at start-up for about 3-5min then maybe goes into an open loop and starts missing. I just read something on the ms website that makes me think my exhaust gas temp is to low for proper o2 operation. I have no cat or mufflers on the car so my temps may be low at idle. I think your problem isn't that it's going open loop - just the opposite. On cold start, the ECU generally runs open loop until the coolant reaches a preset temperature. It starts using the EGO sensor after this temperature is reached. It sounds to me like your problems start when the ECU starts trying to compensate for the EGO sensor readings. This could be for a number of reasons. For one, the EGO feedback is really only useful for making relatively small, long-term corrections, and doesn't handle transients very well at all. If your idle mixture is too far off, the feedback won't be able to compensate. Your idle fuel pressure could be contributing to this. I realize that you had idle problems before the fuel pump install, but this most likely isn't helping. Second, if your EGO sensor is giving funky readings, this could throw any hopes of getting a stable idle out the window. A cold sensor could cause this. How far down the exhaust is your sensor? I'd try to deep it within a foot of the turbine outlet. Also, a heated EGO would work better (I can't can't believe that this didn't come with the kit - they supplied a one-wire? ). You will have to figure out how to wire in the power for the heater, but the three or four wire sensors should work the same as far as the ECU is concerned. Another problem with having the sensor too far down the exhaust is called transport delay. Basically, the farther down the pipe the sensor is, the longer it takes for the exhaust to get to it. This can cause problems with the feedback loop, since it is expecting a shorter delay between the time it makes an adjustment and the time it shows up on the sensor. Oh - and sorry, but you cannot just hook up a WB EGO to the narrowband input on the ECU - the WB sensors require completely different interface circuitry, and have completely different output curves. You could use something like the LM-1, and have it 'fake' a narrowband output for the ECU, but this kind of kills most of the advantages of the WB. You could use the LM-1 to datalog with full resolution though, and this could be very useful, assuming you could reprogram the ECU. My electric fan has also burned out the temp switch so it stays on and is probably keeping my water temp lower than it should be. You should always wire the fan through a relay, and not directly through the temp switch. What has probably happened currently is that the contacts have welded themselves together, which is 'okay' for now. Problem is, if there was enough current to do this, it's also probably enough to eventually melt the contact completely, leaving you with no fan, and this almost never happens at a convenient time. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 2, 2005 Share Posted January 2, 2005 Tim is right about EGO enable signals, make sure the ECU is set to NOT correct the fuel mix until the engine is 1) Warmed to at least 160 degrees 2) AT An rpm above, say, 1500 RPMS with a heated sensor, and 2500RPMS with an unheated sensor (OFF-IDLE !) You do NOT want EGO correction enabled at idle, only light cruise. 3) Get at least a heated three-wire O2 Sensor. I used the one from an 87 ZXT in mine, so I can actually get a proper switching signal as low as 1500rpm---meaning I can get EGO loop while lugging at low speeds like 50mph with my 3.36 rearend! With the stock Z and it's one-wire, remember that the stock ECU only had EGO correction in the range of about 2000-3500 before going open loop (light cruise at speed) as this was the minimum speed that would heat the sensor. The 87 ZXT sensor (or any three wire) WILL heat itself just fine at 1500 and give you much further EGO capabilities. Mine is in the EGO loop from 1500 to 4000, below some TPS voltage I forget. Basically, if you are "on" it, then it's out of service and not correcting, and if you lift the throttle it goes in to closed-loop. I set it up like this in preparation of getting WBO2 support with a switchable signal and setting theswitching point to 16.5:1 AFR for maximum fuel economy at cruise conditions. The heater wires for the O2 sensor are easily driven off the Fuel Pump or EFI relay from the MS box. I use mine on the Fuel Pump Circuit, in parallell with the Aux Fast Idle Air Controller so I can do "key on" troubleshooting without warming up the regulator and killing the proper fast-idle response when I finally do kick it over and start it. I rewired the Stock system in my 78 similarly, since I like that function block a lot... 4) like Tim mentions about the further down the pipe you are the longer delay you have in the tuning loop is correct. I tell people "you should be able to see the sensor from under the hood". My N/A setup is in the collector of the header, and the Turbo cars are right at turbine outlet...within 6" at least. My 75 Fairlady is down the headpipe quite abit, near the transmission halfway point, but on that one it's being concealed from the prying eyes of Emissions Technicians (who think my stock ECU and Wiring Harness are actually housing stock components! muahahha, State of California SMFD!) Watch your injector lights. Like I recently posted, I had a similar symptom where it started running terrible after startup. Idled fine but then went to hell. It was alternator noise. If you don't have a filter on incoming power, just consider it migth be a possibility. Quote Link to comment Share on other sites More sharing options...
datsunan Posted January 3, 2005 Author Share Posted January 3, 2005 Currently I'm running the stock o2 in its stock location but I would like to change out the dp to a 3" with 2 45degs. I will keep the o2 placement in mind thanks. I think I will try the heated o2 sensor if it turns out its not caused by altinator noise. PM to Bernardd follows. My plugs look great when I change them out, good color and all the same. I have been trying to see if it was the wrong heat range of plug but now I'm running NGK 8es7 or something I don't recall right now but they are what many people have said are the right plugs for this engine, inclueding JWT. That would be cool if you could set me up with the link and I can start to study the process to see if I would feel comfortable doing it. I guess I could just keep the chip I have now and put it back in if I really mess it up or can't do it for some reason. I'm going to check a couple more things to try and smooth the idle. One problem I'm having is a week charge from my altinator which does not keep my voltage much above 12v. I have seen my voltage fluctuate at almost the same frequency as my idle miss. The o2 voltage also fluctuates with the same frequency but I don't know which is happening first. At any rate I want to be able to get more power out of my engine but I would also like to start off with a solid running engine. You say the o2 voltage should fluctuate after the engine is warmed up? Is that at idle or when driving. I know it changes with a change in rpm but are you saying it will swing at a constant rpm like 3000? I have seen it swing at idle but i thought that was part of my idle problem cause when it swings thats when it misses but i can't tell what comes first. Shoot me those links when you get a chance Thanks Paul Quote Link to comment Share on other sites More sharing options...
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