I'm not accusing you of anything man :p just thinking out loud :)

For the ECU to re-correct back to stock timing parameters, shouldn't it has to have some sort "backup" tables to remember those values?

I was thinking more on the intake being cooler now due to the meth and the timing adjusting for that. I know the water/meth has something to do with the octane ratings but it also cools the intake. Ive heard of turbo guys doing water/meth without adjusting timing just to cool the intake temps so the air wont be so heat soaked. Im just wondering if it will work that way for the NA too if the ECU adjusts timing for the cooler intake temps. And when I say inytake temps I mean at the injection point I guess.

I wish Cobb would come out and tell us what they have come up with so far as far all this goes.

I got 320.1 rwhp on a dyno jet and my car is a 7 AT. I have the same mods as semtex except that i have stillen headers,
Im running the Cob tune #s that i got from Denny. Primary fuel and i did advance the timing 2 degress on the cobb but it did nothing. I also change my throtle postion settings.
Acording to the Cobb A/F readings im running lean at diferent rpm bands, but between 6800 and 8000 i picked up at leaset 12 RWHP. the A/f is around 13.6 to 13,8.
Now im not to sure how acurate the cobb is at reading a/f . i also run on Sunoco 94.
i also had my dealer bump the timing By 2 degress with the consult 3.
The difference in the car was night and day. Not sure what changed in the ecu but it made a very big difference.

So you were able to get the timing bump from the dealer and have it stick but not the cobb? And the timing bump made a good bit of diff? I have the AAM tune for my mods and my AFR is 14.7 at idle and in the 12s at WOT. So I wonder why yours are a little off?

Your dealer was fine with doing the timing?

Zeliminator you have the final gear change right? If so who did you order thru?

We are dynoing my car on thursday and tuning it with uprev, I will not be to aggressive but I think a time degree or two etc.. Try to keep the AF at 12.7-12.9. who knows what i will happen with the car.

I bought a whole diff. from a nissan mechanic from a g 35 / he did all the work and changed out the gears, he told me that the parts cost around 800 to 850 dollars.
I can not wait to see what the 4.08 will do with my GTM SC.
I got the A/F from the Cobb. I was told by Denny that they are not acurate depending on what A/F #'s that you are getting , They could read too high on the top end and at the bottom end the reading may be ead to high. "this is what i have read on the forum. If any body has compared the cobb readings with actual A/F readings from a tail pipe or external wide band i would be very interested to see how they compare."
My car does not ping but man does it go. I have added more fuel to the curve now, i dropped the #'s eg. from 87 to 86. ect. 77 to 76 I did this for the entire fuel curve. I have not dynoed the car with these changes Not sure how much of a change it will make.

i will try to post my results thursday night after or friday night after work. i would be shocked to get these type of gains on thursday.

Incase anyone is interested this is an email response I received from Sebastian @Specialty Z (authorized Uprev tuner in CA). FYI they charge $500 for license, tuning and dyno time.

"Yes, there are some conflicting thoughts. AFR will change and that's about it. I tuned a G37 that didn't react to the speed limiter :(
Uprev couldn't help me out or my customer on that one. Timing is tricky. We have access to the IGN maps but they don't seem to take. I changed the timing quite a bit to see if I could get some result and I could only get it too lose power :(

So as of right now we can do AFR, timing is up in the air (looks like a negative), VVEL is no go yet, rev limiter, and on a couple G37s the speed limiter wouldn't take. The 370s seemed to be fine. Tuning the AFR can make some decent, low, or no gains like you mentioned. On a G I did it gained a good amount of power considering. On a couple 370s we were able to get around 5-7 HP. The main goal would to at least make the AFR safe when modifying the car. Making it safer would be the goal. Power would be a icing on the cake. As you can tell, the bugs are still being worked out with the tuning software.

take care!"

That's weird, my rev limiter was bumped up to 8k and the rpm cutoff was also narrowed down

Have you actually driven it all the way to 8k though? Because mine was bumped up too. But then we discovered that the rev limiter still kicks in at 7500.

Yes I did, I'll get some footage for you next time I'm in the car

No need. I believe you. :tup: I wonder if it's just a matter of some ROM files being more 'agreeable' to the parameter changes than others. I don't know how else to explain the inconsistency of results with some cars accepting the rev limiter bumps and others just ignoring them.

If you also noticed in the video's I recorded of my exhaust, you can hear the aggressive rpm cut-off. The cutoff band was set to around 200rpm before the tune, I had it brought down to 50 rpms after the tune.

so I think this has already been kind of answered but does anyone know what type of power could be achieved when the vvel gets unclocked?

Just guessing i would say you could tune out maybe 20whp N/A and maybe 40+ F/I . I dont think the total gains are going to be as important as the ability to keep power up thoughout the power band. Also will help a lot with keeping turbo lag low. Most gains will be in the low end do to the vvel trying to keep emissions low.

^ there is no answer bc no one knows. Only time will tell

It's all about the right combination when it comes to upgrading cams, on the VQ35 I read gains of up to 20whp (with the right intake & exhaust setup)

The fact that those are efficiently tuned from Nissan makes them a challenge on our engines though. I wouldn't be surprised if tuning the VVEL made zero gains on a stock VQ37. Don't forget the exhaust cams will also have to be upgraded

My charts got screwed up when they tried to save them, but Chris and I just got back from tuning from Uprev and found and extra 15-17hp (depends on the mapping) and 5lb-ft of torque on all maps. It was a lot hotter out today from my posted dyno results but that is what we found from the base dyno pulls today. really happy with the results and failsafeperformance's tuning ability with Osiris Uprev software. He was able to answer all my questions and explain what he is doing with each adjustment. So I feel really good about instead of butterfly from messing with my ECU. We have to do a few more so hopefully will be able to post those results with the final mapping.

Those S-curves you pulled after the dyno were scary as hell. You sir, are crazy! :rofl2: Wicked fun though! Can't wait to see what you can do on the road course.

Oh, and I'll try to get some graphs posted up today.

I am stoked for the track, and can't wait to get the final map done and adjusted to tweak every little bit of performance out of the current set-up.

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SEMTEX - I think the limiter issue has to do with the tuners input, you have a limit for throttle and two for fuel, the idea that one is a gradual decline and one is a hard stop etc
Your throttle limit should be set lower then your fuel cut.
Sam - awesome ride man

Congrats and good numbers Sam, I know we aren't best of friends, but I'm trying haha.

Not sure I'm following on this one. Sharif showed me the screen. There's a single field where you can enter in what rpm you want the redline set at. He set it at 8k, but my rev limiter still comes on at 7500.

I deleted my uprev editer a couple of days ago, I assumed that UPREV had access to the same tables as COBB, maybe they do only have one area for rpm limit setting, that could be the issue if there is still a limit inside your ecu unchanged?
I will down load the UPREV editor again and take a closer look - cannot download form PROC - take a look at your own hex file (or what ever format UPREV use) and see what tables are open or if locked by tuner look at a stock rom image.

when we tuned my car the other day, we could only tune up 6400 rpm. that is all the program would show for fuel tables. Has everyone else experienced the same thing. Uprev said we have to ratio out the table? Not sure why we would have to ratio out when my buddy 350Z showed his entire RPM band. Anyone else experience this?

:confused:

You know what? I'm just going to say it. Uprev's support for the 370Z right now is half-baked at best. I'm really not very impressed.

I am half tempted to get a dyno tune with cobb, but I know Uprev did a very good job for the 350z crowd, from those I have talked to in Houston.

Yeah I know. For the 350, Uprev is IT. And that's why I went with them for the 370. But I have to say I'm disappointed with what they've put out thus far. They have not measured up to my expectations, which I based on their reputation in 350Z circles.

Maybe I will keep my LTH off for awhile then until this whole tune thing gets resolved.

Problem is you might be waiting an awful long time. Just go ahead and put them on now and use the tune to adjust AFR. You'll get some gain out of a tune, just don't set your hopes too high is all. The G guys seem to be getting better results though. Same engine, but the ECU ROM files are different.

As in this half baked?

Probably true, would love to finally hear the exhaust fully opened since I am on still stock cats.
Just sucks that right now I have to drop so much for a simple AFR fix. :shakes head:
The other bet is, will Uprev come out better or will Cobb? Both can do simple AFR fixes, but down the road will be the true winner.

right now I think Cobb and Uprev are doing this about the tune.

Im in a visual mood.

Can some one open there UPREV rom and post up an image of tunable parameters

Here is list of current COBB avaliable tunable areas.
Notice COBB only goes to 7200 in fuel area, above this the ECU will still hit target based of the current table data, at 7500 it should match the 7200 targets relevant to load injector setting etc. Hope that makes sense.
NB - I am not trying to push COBB over UPREV. What we really need is a third party option with cable purchase (simular to the Subaru and EVO, Honda platforms) and downloadable software, I suspect in the future more options will become avaliable.
Anothe roption for fuel fixes , all be it a bit crude , would be some one to develop MAF tubes slightly over sized but properly/accuratly calibrated that could be incorparated in some way, personally I would wait for a MAF tuned AFR fix.
http://i116.photobucket.com/albums/o...1/cobbaval.jpg

So to answer my own question, people are having the same issues as me?