oh by the way brad good work. Very clean setup.

 

ah its nice having friends with widebands isnt it ha

 

If you can't get the a/f acceptable thoughout the rpm/boost range, you might want to consider a SAFC. Instructions via mr.goober is in the 3-gen stickies.

Again, nice job

 

Thanks Jeff, I may consider that. Money is kinda tight right now though, so I wouldnt be able to get it until the summer. The SAFC can adjust fuel based on rpms I know, but throttle position also? I was also looking at going with the Zemulator, since that seems like the best way to tune, at a decent price (comparitively).

 

yeah, the s-afc can adjust fuel per the rpm and the throttle position. its definitely nice for adjusting partial throttle (i.e. cruising down the highway, etc.). messing around with it a bit while cruising i got about 28.5 mpg once... and could easily have gotten quite a bit more.

really, the things are best for small adjustments when used with something like the zemulator but can do large adjustments.

 

So would you recommend one in addition to the Zemulator? If thats the case then I'll probably pick one up.

 

well... i guess it really depends on how easy it is to fix the fuel curve using the zem. theoretically you should be able to do the exact same thing with the zem as the s-afc but to a much further extent (and using a better process i.e. changing the fuel curves themselves instead of the maf reading).

basically, if you can datalog all of your driving from part throttle cruising up to wot tire shredding you should be able to perfect the entire fuel curve with the zem alone. the only downside that i could see is that what's nice about the s-afc is that you can just pick it up while driving and adjust the fuel curve right there to perfect your afr on the spot. (note: its not a good idea to tune while driving... but i do it anyways )

if you're planning on getting the zem, i'd personally get that first and tune everything. if from there you can't perfect something i'd get the afc to do the final adjustments needed to perfect it.

 

Hey guys, maybe you can help me out... I seem to be having a small problem. Yesterday I noticed that the car will be fast for a bit, then become sluggish after getting into the gas a few times. I assume its pulling my timing since I can turn the car off then restart it, and it will be fine again. I don't hear any knocking/pinging, and my timing is set at the stock 15 degrees. Would decreasing my plug gap help this at all, or is the only solution to manually pull back my timing? Thanks.

 

what are the gapped to now?

 

Stock gap, 0.44 i think

 

go at least .038

 

ZEMulator should be all you would ever need. No SAFC.

I want it for 4th gens.

 

change your plugs to a colder plug, solved a lot of problems for me. Invest in the zemulator, you are eventually going to want more power, and this thing makes tuning for large injectors a breeze, especially if you come close to the 400whp mark.
great job by the way

 

Is the zemulator that program ive been hearing about that requires a laptop? Anyone have a thread link handy?

 

Sorta hard to tune with the Zemulator as it's not even available for the maxima.

 

i was waiting for somone to smack the reality back into the conversation

im patiently waiting but at this piont im keeping my options open cause this may never even happen

 

I'm going to use the lack of the Zem as a method to keep myself on the 3.3". I've set a rule for myself that I'm not going to go smaller until it comes out.

 

Well tonight I moved my MAF to the straight pipe by the radiator, and I have no more bucking/rough idle problems. Runs smooth as silk! One problem I am having though, is that under WOT in the high rpm's the wideband will kind of freak out and read really lean (i.e. 50:1 AFR) and just go into percentages, like it does when I let off the throttle. I hear no detonation and it doesnt hesitate, so I'm thinking it is because I have the O2 at a location before the wastegate re-enters the exhaust stream. The bad readings only happen at full boost, so its logical to me.

I also got the timing problem fixed, and it doesnt pull it back anymore. I had to advance it quite a bit, for some reason the marker was wayyy off of the tick marks (on the retarded side). I put the timing to around 12 degrees, it was had to get a good reading.


Wait, I thought Aaron said that Ash made one for the VE? At least that was my understanding, it was just the VQ program that was not ready.

 

When You Get This Thing Tuned How Much Boost Will You Be Pushing? How Much Are You Pushing Now?

 

Its pretty much tuned now, I'm running 6 psi. I plan to up that to 12 psi when I get the money for bigger injectors and fuel management.

 

Good to hear you fix your problem,have you dyno it yet at 6psi?

 

Aaron92SE is using Zemulator on his VE right now. Not sure if that's a prototype or a ready to use edition though.

 

thats a good guess on the A/F readings i would move the wideband O2 to a section of the exhaust a little further down stream where it sees the wastgated exhaust

 

any updates brad? i would like to see what kind of numbers your car puts out.. btw, did you upgrade anything else to your car other than the turbo ? injectors, MAF? what fuel pressure are you running at at idle and at full throttle?

 

I occasionally get the same thing with my SC'ed setup, so I don't think it's wastegate related.

Misfiring at high rpm will result in high oxygen content in the exhaust that the WB O2 sensor detects. If you have only one plug misfiring at high rpm you won't feel any hesitation or significant power loss, but you will get the high O2 content reading.

Overheating the O2 sensor will also cause it to read lean, but my setup (Innovate LM-1 with a Bosch LSU4.2 sensor) should be giving me an error code when that happens, and I'm not getting one.

What WB setup are you using?

 

Everything else on the engine is pretty much stock, stock injectors, MAF, etc. My idle fp is around 39 psi and WOT hits close to 80 psi.



I'm using the same one you have, LM-1 with the Bosch sensor. I have it in the downpipe probably ~20 inches from the turbine. It is very close to where the wastegate re-enters, could some turbulence give bad readings?

 

Turbulence in and of itself shouldn't cause any problems, unless free air is being sucked in through the wastegate. I don't know if that is possible. It may be a temperature issue - the Bosch sensor is good for up to 1300 F, I believe, and it is possible to get higher temps than that if you're not far enough away from the engine. But like I said, the LM-1 should be giving you an error code if the temp gets too high.

I think it is most likely a plug misfiring, though. What plug gap are you using?

 

I gapped the plugs to 38. They are the factory NGK plats.

 

You might try reducing gap to .034" and seeing if that improves the situation. During high-rpm boosted conditions a large gap can result in spark blowout due to turbulence in the combustion chamber.

 

Here's a little update on my ZEMulator project. Me and Ash are still trying to work the bugs out. It's not quite ready to be released. I still don't have it working 100% in my car. Ash has a lot of stuff to try out and he WILL get this working. His motivation isn't the VE maxima, it's the 95+ z32, which has the same design ECU as the VE Maxima. He already has this working in the z31 and the VG30E Maxima. Somebody just needs to step up and buy it for the VG30E Maxima.

Right now, I don't have it installed in my car. I sent the setup back to Ash, where he is currently working on it. I don't expect this to be done within the next month or two. But, I won't install my turbo until I know I have a great tuning setup. There is no way I will mess with that SAFC or emanage stuff. The ZEMulator and a wideband o2 sensor is all you ever need. A dyno wouldn't hurt.

http://ashspecz.com/ashspec/zem/zem.htm

BTW, awesome freakin job on the turbo Brad!! I still haven't decided on how I want to route my piping. But that setup is one of the easiest and best setups you can do. Get it tuned!! I want to see some track numbers!

 

aaron, does he still have the ecu that i sent?

 

Thanks for the update Aaron! For right now I'll probably just go with a wideband setup, although I'm having a little trouble picking one out (I'd like to have it permenantly mounted). As for the tuning, aside from the erroneous readings that I discussed earlier, the car is pretty much tuned. I may get an SAFC come summer if the Zem isnt out by then, and I have the money, just to correct for some part-throttle richness. I'll get some pics of my new intake piping this weekend. As for track numbers, I'll be putting up what I can on April 9th, I'm kinda hoping for 13's. I definately think that its possible, provided I get some sort of traction.

 

Yeah, I mainly interested in your trap speed. That will give me an idea on what kind of power your making. Make sure you post up your entire timeslip.

As for the wideband, I have a PLX Devices wideband o2 sensor and it's awesome! It's cheap and easy and it was the perfect linear signal for the ZEMulator to accomodate.

Slimer, I don't know what Ash is doing with your ECU. You'll have to contact him yourself. I live several hours from him and I have never even met him in person. Once he gets this working for the VE ECU, I will drive up to Daytona, where he is, and we will dyno tune it and he will then release it to the public.

 

What PLX model did you buy? My main concern is that I want to be able to datalog with it. Will the Zem be able to datalog the sensor even if the kit doesnt have the datalogging capabilities?

 

Oh yeah! That's the greatest things with the ZEM. You can datalog ANY sensor you want. So I bought the PLX wideband that doesn't have datalogging capabilities. I got the simple one that has the digital display. I think it's the M-300 or something. It was $330 shipped.

Honestly, I would recommend that you don't spend the money on the PLX wideband setup that doesn't have datalogging capabilities. Save some money, get one that has a digital readout and get the ZEM just as soon as I get it working.

 

Yeah, I paid $339 shipped for the M-300 with Bosch sensor.

http://www.plxdevices.com/onlinestore_domestic.htm#q3

 

Today I regapped my plugs to 0.034, and pulled back my timing quite a bit (it was at 20 deg. for some reason), and I am still having bad o2 readings on the wideband. I notice no misfiring, and the car is running pretty rich, around 11.0 at full throttle before it goes haywire. The readings will suddenly spike to 40.0 AFR and above. Sometimes it will read percentages as it does when I let off the gas. The car doesn't backfire or anything. I can't see myself locking up or maxing out the injectors, since I am only hitting ~78 psi of fuel pressure and the car still accelerates in spite of the o2 readings. The bung is located close to where the wastegate re-enters the exhaust, but does not see that exhaust. It is about 30" from the turbine. Has anyone had similar problems? Although nothing seems to be going wrong with the car (*knocks on wood*) the readings are scaring me and I don't want to get into the gas too long. The bad readings happen when at full boost, but not all the time. They only happen when at high rpms, at greater than half throttle. Any thoughts?

 

Will this logging be at the same dinasaur speed that plauges most Nissan ECU's? I don't know what the Z32 is but most N/A Nissans get readings between 6-15 samples/second. Or is that just what is put out through the OBD-II plug? I have heard that but never got a solid answer if that was true. It would make sense to me that the ECU would need to be much more precise but why not just send all the raw data to the OBD plug?

 

I'm not sure what the sample rate is on the ZEM. I know the first BETA version of the ZEMulator a long time ago had a few complaints about the sample rate. So Ash edited the software so that it samples much faster. I don't know exactly what it is, but it's more than is needed to properly tune any kind of beast you may have. You will have to email Ash with that question.

Brad, I was taking a closer look at all your pics last night and I have a few questions. What kind of fitting did you weld in your oil pan? It looks like a Home Depot galvanized plumbing fitting. Where did you do all your shopping when it came to hoses and fittings for your turbo? Also, I am curious how you welded the BOV fitting on your tube. That looks very difficult. I know your wastegate welding job was a little pain, but the BOV welding looks harder. Any tips?

Also, you say you can reach full boost at 3K with this turbo? If that is so, then I will get the 60 trim and not the 50 trim.

As for your fuel problem, the AFR is suppose to go way lean when you let off the gas b/c the ECU cuts the fuel on deceleration. 11:1 is just fine. I would leave it for the time being. The stock VE ECU has a 11.5 to 12.0:1 AFR. Leave it at 11:1 if it's a steady smooth AFR line. Once you get your car tuned perfectly, then you can lean it out a bit more to get a few more HP. Can you tell me how your AFR looks when you're doing a WOT run from 3K to redline? Does it stay at 11:1 all the way? Thanks.

 

Yeah, the fitting I bought from a local harware store. I wouldnt recommend galvanized though, get black pipe. The galvanized gives off a gas and white residue when you weld it. I bought all my hoses and fittings for the feed/return lines from a local place, Riverbend. All of that ran me 80 bucks. As for the welding, the BOV fitting was actually cake. I bought the steel flange off of Ebay, and it had the correct radius machined in it to fit on a 2.5" pipe. I did grind off the weld though. The hardest welds were when I had to make a slight bend, or when the cuts didnt match up perfectly, and there was a gap to span with a weld. Sometimes it ended up cutting though the pipe and I had to patch it up.

I do reach full boost around a little over 3K, depending on what gear I'm in. This seems to be a great street turbo, with a mix of some low-end boost and plenty of high-end.

As for the AFR, it goes way lean when I am still in the gas. At low RPM and part throttle, I am running pretty rich due to just having an FMU. At high rpm I'm not sure what I'm at, the last good readings that I get are around 11.3 or so before it spikes lean.