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? Use nitrous to override the factory rev limiter ?

Nitrous Discuss dry, wet, and direct port nitrous setups. How many shots can you handle?

? Use nitrous to override the factory rev limiter ?

Old 12-22-2008, 01:49 PM
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Originally Posted by grey99max View Post
Note that tirmax said that JWT built a re-wired and re-programmed '96 ECU for him to replace his '99 (and some things don't work now)- and I know the ECU pinout for '99s is different from the 95-98s, so anything nistune builds won't have a '99 pinout - right? And do they build an ECU for any of the '95-'99 USA Maximas? Pinout is different, functions are different - I'm not seeing this work.
All that JWT did was rewire a 96 ecu to fit in a 99. The 99 and 96 ecu's have different connectors. If you wire a 96 ecu connector to your 99, a 96 ecu will run your VQ. Last I heard, Nistune was testing their product on a 95-96 maxima ecu and it was working flawlessly.

Did you read the link I posted in post #33?

I see that you are planning an engine build and I'd hate to see it not perform to it's full capability due to the lack of tuning capabilities. Just trying to help.
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Old 12-22-2008, 02:02 PM
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Originally Posted by 505max94se View Post
All that JWT did was rewire a 96 ecu to fit in a 99. The 99 and 96 ecu's have different connectors. If you wire a 96 ecu connector to your 99, a 96 ecu will run your VQ. Last I heard, Nistune was testing their product on a 95-96 maxima ecu and it was working flawlessly.

Did you read the link I posted in post #33?

I see that you are planning an engine build and I'd hate to see it not perform to it's full capability due to the lack of tuning capabilities. Just trying to help.
I know that, and I appreciate it - and yes, I am planning on another 3.5 build, heavy on the nitrous and custom engine parts. But, please appreciate that ECU wiring affects a lot of things in the car, so any changes need to work well with existing systems. I'm sure that the JWT re-wire of a '96 leaves out some newer '99 functions - the NAT key security function is just the first one to go. Don't know what Nistune has done - nothing on their web site says different about '99s...

I'm not willing to spend lots of time figuring out why something in my '99 stopped working due to a custom ECU - not if I can just spray nitrous above fuel cut to keep it spinning. That's where I started from, anyway...
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Old 12-23-2008, 02:03 AM
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Nistune has a board out for the VQ30DET... So im sure it wont be much longer. I know they just recently released boards for late 90's SR, KA, and RB motors.
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Old 12-23-2008, 06:26 AM
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I don't think I would extend the rev limit for nitrous. If you do the UTEC is the only way to go.

My record runs were made with 6500 limit, the nitrous makes much more of a difference at the lower RPM's I only use the 7200 limit for N/A.
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Old 12-23-2008, 04:02 PM
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Originally Posted by grey99max View Post
That's interesting - the SE-L is a 99.5 model, so JWT was able to put in the wiring and coding in your 96 ECU to make it work....

Did you provide JWT an original ECU or did they have the code?
Does your NAT still work?
Did they give you any options about rich/lean or ignition advance changes? Does your JWT ECU have all the other functions of your '99?
Did they ask for a 96 ECU for the conversion?
Did you talk to anyone special about your conversion?
Does your engine have any performance mods working with the ECU?

Bunch of questions, but important stuff.......... (nice color, by the way)

.

I talked to Ben at jwt. You use an ecu from 95-96 but they say they prefer a 96 for some reason. They did a NA program. I still have keyless entry w/my remote. I havent checked on the coded key cause I have my spare key being used for my remote start. I havent gone to make a spare at home depot to check it. I have all the boltons done to the car, I,y,e,mevi, and ecu. I dont have any idle problems. Just the cel for egr crap and for some reason automatic transmission code when the ecu was from a 5spd.
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Old 12-23-2008, 04:42 PM
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Originally Posted by grey99max View Post
?
Did they give you any options about rich/lean or ignition advance changes? .
when I called jwt I told them I like to spray and asked if they would do a ecu with stock timing, extended rev limiter and a a/f for my car with a dyno sheet provided they said sure, in fact they would even do a ecu with stock a/f and timing with only a rev limiter extended but it would all be the same price and still take around 6weeks

oh and they also told me to get a 95-96ecu cause they can not do a 97
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Old 12-24-2008, 07:14 AM
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Originally Posted by t6378tp View Post
when I called jwt I told them I like to spray and asked if they would do a ecu with stock timing, extended rev limiter and a a/f for my car with a dyno sheet provided they said sure, in fact they would even do a ecu with stock a/f and timing with only a rev limiter extended but it would all be the same price and still take around 6weeks

oh and they also told me to get a 95-96ecu cause they can not do a 97
Thanks - that's what I thought - no 99s....
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Old 12-24-2008, 07:23 AM
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They do work on 99's. Its in my car. Zack342 also had one and he was a 99
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Old 12-24-2008, 08:26 AM
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Originally Posted by tlrmax View Post
They do work on 99's. Its in my car. Zack342 also had one and he was a 99
And does your NAT work? You know, the chip-in-the-key security lockout?
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Old 12-24-2008, 08:55 AM
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Originally Posted by Jime View Post
I don't think I would extend the rev limit for nitrous. If you do the UTEC is the only way to go.

My record runs were made with 6500 limit, the nitrous makes much more of a difference at the lower RPM's I only use the 7200 limit for N/A.
Aren't you curious to see if the idea will work?? Anyway, here's my warped logic for the future.

Here's a chassis dyno of four pulls, three with nitrous: #2 = 50-shot, #3 = 50+50-shot, #4 = 50+75-shot...



Note the difference between pulls 3 and 4 - the shop guy lifted off the second stage on #4, but #3 was climbing to fuel cut. Note the two different stages being fired off, the first around 3500 and the second around 4500, again by the shop guy. What I see here is that if I could extend the rev limit to 7000 or more, that I could pull hard up to the new limit. Especially if I spray a third stage to make more power from 6000 to 7000 - safer to do on a built engine.

My PLX logs showed that the car accelerates very hard up to the 1-2 shift and 2-3 shift, with no signs of slowing down before the shifts. A little nitrous-cut just at shift time (6500) helped the tranny do that quickly. I had a nitrous cut set for 6400 and I would hit that limit before the traps every time, slowing me down a bit in the numbers. Over 5 passes on two tracks, I had a 1/2 sec variance in ET but trap speed (113 MPH) was within 1 MPH for all. Topping out in third gear....

Anyway, this is why I want to extend the rev limit to 7500 - a seriously-built engine will have no trouble hitting those revs while seeing up to 275-shot total spray - maybe more.....

Forged rods (no Chinese parts) forged pistons, super-light valve train, professional ported heads, C2 cams, and all the other little things should make an engine tough enough to spray hard.

.

Last edited by grey99max; 12-24-2008 at 11:10 AM.
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Old 12-24-2008, 12:11 PM
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Originally Posted by grey99max View Post
Thanks - that's what I thought - no 99s....
they told me I can use a 95-96 ecu but it will just throw a code
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Old 12-24-2008, 12:30 PM
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I knew that some guys were successfully using a 96 ecu in their 97-99's.

This also means that if nistune produces an ecu for the 95-96 maximas, it will also work in 97-99's.
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Old 12-25-2008, 05:22 AM
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Originally Posted by grey99max View Post
Aren't you curious to see if the idea will work?? Anyway, here's my warped logic for the future.

Here's a chassis dyno of four pulls, three with nitrous: #2 = 50-shot, #3 = 50+50-shot, #4 = 50+75-shot...



Note the difference between pulls 3 and 4 - the shop guy lifted off the second stage on #4, but #3 was climbing to fuel cut. Note the two different stages being fired off, the first around 3500 and the second around 4500, again by the shop guy. What I see here is that if I could extend the rev limit to 7000 or more, that I could pull hard up to the new limit. Especially if I spray a third stage to make more power from 6000 to 7000 - safer to do on a built engine.

My PLX logs showed that the car accelerates very hard up to the 1-2 shift and 2-3 shift, with no signs of slowing down before the shifts. A little nitrous-cut just at shift time (6500) helped the tranny do that quickly. I had a nitrous cut set for 6400 and I would hit that limit before the traps every time, slowing me down a bit in the numbers. Over 5 passes on two tracks, I had a 1/2 sec variance in ET but trap speed (113 MPH) was within 1 MPH for all. Topping out in third gear....

Anyway, this is why I want to extend the rev limit to 7500 - a seriously-built engine will have no trouble hitting those revs while seeing up to 275-shot total spray - maybe more.....

Forged rods (no Chinese parts) forged pistons, super-light valve train, professional ported heads, C2 cams, and all the other little things should make an engine tough enough to spray hard.

.
I tried both ways, 6500 and 7200 limit with a 75 shot the 2nd last race day and the 6500 limit was quicker, not by much but definately quicker. Just the reverse N/A. I am even thinking about trying lower in the 6000-6500 range.
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Old 12-25-2008, 12:31 PM
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Originally Posted by Jime View Post
I tried both ways, 6500 and 7200 limit with a 75 shot the 2nd last race day and the 6500 limit was quicker, not by much but definately quicker. Just the reverse N/A. I am even thinking about trying lower in the 6000-6500 range.
That's interesting... so you think that torquing your way down the track with lower shift points might be worth testing out? But that was with a single 75-shot, and I'm wondering if an additional shot in the upper RPMs might be even better ??

As I recall, you've tried several things with a progressive controller. Did you see any benefit to spraying more at the top?

Merry Xmas to you and yours.....
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Old 12-25-2008, 07:19 PM
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Originally Posted by grey99max View Post
That's interesting... so you think that torquing your way down the track with lower shift points might be worth testing out? But that was with a single 75-shot, and I'm wondering if an additional shot in the upper RPMs might be even better ??
Well for the most part nitrous appears to give a disproportional benefit lower in the RPM range than in the upper.

My guess (pretty easy assumption) is since it adds the SAME amount of nitrous/fuel the entire time it's spraying, there is a much larger total impact while the engine is at lower RPMs and using less total fuel/air in the first place, more nitrous/fuel is going into each chamber over time because there's less combustions per second. Up top when the engine is spinning way faster, less nitrous goes into each cylinder during each combustion cycle meaning less realistic gains b/c of the RPMs being higher while the same amt of nitrous is being sprayed into the IM. This is usually why you can spray more and more nitrous as you get up in the RPMs without having any issues, you need more nitrous to get the same %age gains. It's like having a turbo that "maxes out" or applies a static amount of boost (lets say 10psi for comparison) at 4000 rpms. By the time you reach 6000 rpms, the boost will have dropped considerably b/c the engine needs more air to breath.

Considering all that junk, if you're spraying say a 100 shot, you will get more gains out of it at lower rpms, so it's likely you're best off shifting earlier, OR adding a progressive controller (ramp up shot per rpms) or just a 3rd stage for 5500+

If you're gonna spray higher than 6500 for gearing effects, I'd spray a bigger shot up top as long as your engine is built for it (seems yours is going to be).

I really, really think you should find a way to make the UTEC work or just use a EMU while you have the 3.0 timing stuff. Full control of timing and reliable fuel maps up top will make that built engine much less likely to pop b/c of something stupid, like spraying a crapload of fuel into the IM with a fogger nozzle!!!!

If it's not an option because of money, save up and do it the right way imo. Even if this works "reliably" 99/100 times, there's going to be that one time that a cylinder runs lean or the fuel solenoid fails etc etc while you're up there above the limiter and that's all it'll take.

blah blah blah wall of text. merry xmas

Last edited by sparks03max; 12-25-2008 at 07:23 PM.
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Old 12-25-2008, 08:04 PM
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Originally Posted by sparks03max View Post
Well for the most part nitrous appears to give a disproportional benefit lower in the RPM range than in the upper.

My guess (pretty easy assumption) is since it adds the SAME amount of nitrous/fuel the entire time it's spraying, there is a much larger total impact while the engine is at lower RPMs and using less total fuel/air in the first place, more nitrous/fuel is going into each chamber over time because there's less combustions per second. Up top when the engine is spinning way faster, less nitrous goes into each cylinder during each combustion cycle meaning less realistic gains b/c of the RPMs being higher while the same amt of nitrous is being sprayed into the IM. This is usually why you can spray more and more nitrous as you get up in the RPMs without having any issues, you need more nitrous to get the same %age gains. It's like having a turbo that "maxes out" or applies a static amount of boost (lets say 10psi for comparison) at 4000 rpms. By the time you reach 6000 rpms, the boost will have dropped considerably b/c the engine needs more air to breath.

Considering all that junk, if you're spraying say a 100 shot, you will get more gains out of it at lower rpms, so it's likely you're best off shifting earlier, OR adding a progressive controller (ramp up shot per rpms) or just a 3rd stage for 5500+

If you're gonna spray higher than 6500 for gearing effects, I'd spray a bigger shot up top as long as your engine is built for it (seems yours is going to be).

I really, really think you should find a way to make the UTEC work or just use a EMU while you have the 3.0 timing stuff. Full control of timing and reliable fuel maps up top will make that built engine much less likely to pop b/c of something stupid, like spraying a crapload of fuel into the IM with a fogger nozzle!!!!

If it's not an option because of money, save up and do it the right way imo. Even if this works "reliably" 99/100 times, there's going to be that one time that a cylinder runs lean or the fuel solenoid fails etc etc while you're up there above the limiter and that's all it'll take.

blah blah blah wall of text. merry xmas
Wow - that's a considered opinion or two..... Yup, you get a bigger boost from nitrous down low because nitrous is all-or-nothing (at least for one nozzle/no controller) - and doesn't change unless you spray another nozzle - agreed. Your turbo reference is good - no more boost "at the inn" once the maximum is reached.

Money isn't the problem with the UTEC - having to use a 3.5 flywheel to sync the UTEC is a problem in a 4th gen w/3.5 and 4th gen ECU and 3.0 flywheel and 3.0 timing stuff - and no, I'm not going to convert the car to a 3.5 ECU - too much cr*p to convert and I don't have that much spare time. All piggybacks follow the stock ECU parameters, and those wander around too much on the 4th gen ECU - a piggyback would just magnify any problems, and is hardly "full control of ignition and fuel maps". This is no place for approximations, IMHO.

I think a modified stage of spray would work to extend RPMs as long as rumors of extended ignition to 8,000 are true - I can put an oscilloscope on the coils to check that first.

I really would like to use the UTEC - if I can find a way to get 3.5 flywheel timing pulses to feed it - then it would be useful.

Merry Xmas......
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Old 12-25-2008, 08:13 PM
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Well since you're using all 3.0 gear, why not use an EMU? They seem to work great.

edit: also, the UTEC works as a sort of standalone/piggyback, and takes over full fuel/timing control from the stock ECU when you start making value changes. Thats why some of the 350z guys complain of a "shudder" on their turbo'd car when they start making boost and the UTEC takes over control. I am not sure if the EMU does the same, but it must do something similar in order to bypass a rev limiter.

edit2: meh thinking through all this just makes me excited to know i'll have a HPtuners box on the LS1... lol. Carefree tuning ftw

Last edited by sparks03max; 12-25-2008 at 08:22 PM.
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Old 12-25-2008, 08:52 PM
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Originally Posted by sparks03max View Post
edit: also, the UTEC works as a sort of standalone/piggyback, and takes over full fuel/timing control from the stock ECU when you start making value changes.
Unless you have a 3.5 flywheel, the UTEC won't work - it needs the 3.5 crank sensor and 3.5 flywheel timing signals. The stock '99 ECU needs the 3.0 flywheel and 3.0 flywheel timing signals. You can't have both in the same car.

Sigh...
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Old 12-25-2008, 08:55 PM
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Originally Posted by grey99max View Post
Unless you have a 3.5 flywheel, the UTEC won't work - it needs the 3.5 crank sensor and 3.5 flywheel timing signals. The stock '99 ECU needs the 3.0 flywheel and 3.0 flywheel timing signals. You can't have both in the same car.

Sigh...
Yeah I understand, that sucks, are you totally against EMU? Even if it is a piggyback, it will be much easier to beat the limiter, you can pull timing, and feel safer with that big shot.
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Old 12-25-2008, 09:05 PM
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Also, I wonder if there's a way to make a signal converter for the crank/flywheel sensors to mimic a 3.5 using 3.0 signals? I'm 100% sure it could work, as long as you can get the #s right... similar to how people use signal conversion boxes for oem guages on swapped cars. It may be as simple as setting up or having someone setup a nice microcontroller to react with a certain output for each input (giving 3.5 sensor outputs with the 3.0 inputs)
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Old 12-26-2008, 08:11 AM
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Originally Posted by sparks03max View Post
Also, I wonder if there's a way to make a signal converter for the crank/flywheel sensors to mimic a 3.5 using 3.0 signals? I'm 100% sure it could work, as long as you can get the #s right... similar to how people use signal conversion boxes for oem guages on swapped cars. It may be as simple as setting up or having someone setup a nice microcontroller to react with a certain output for each input (giving 3.5 sensor outputs with the 3.0 inputs)
OK - you're a mindreader, right? I'm been thinking about that, and considering that there are 359 teeth (with one gap) on the 3.0 timing ring (but the flywheel is not indexed) and a lot fewer points on the 3.5 flywheel (and the 3.5 is indexed on the crank) I wonder if I can put the two on a 3.5 block separately and use a degree wheel to map the 3.5 timing points. I've got both versions here so I can look. The 3.0 and 3.5 crank sensors are also different so I would to need to match output pulse formats as well. (I do electronics - oh, yeah)...

Something to think about doing - probably before i get the 3.5 short block torn down, tanked, and measured for wear - including bore sizes....

EDIT: the 3.0 flywheel has a full set of teeth (unlike me) but has only 180 teeth. I have no idea why I was thinking there were 359 teeth. I'll take photos of both of them for later...

Last edited by grey99max; 12-28-2008 at 03:12 PM.
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Old 12-27-2008, 09:22 PM
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grey just curious have you ever hit the rev limit while spraying before? if you have then i don't think you can over ride the rev limit by spraying extra fuel through the intake. i have hit the limiter on my 2000 twice while spraying and it hit at my normal rev limit both times. i also had my nitrous set to run a little rich, like 10.5 afr rich.
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Old 12-28-2008, 02:28 PM
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Originally Posted by xlcrew View Post
grey just curious have you ever hit the rev limit while spraying before? if you have then i don't think you can over ride the rev limit by spraying extra fuel through the intake. i have hit the limiter on my 2000 twice while spraying and it hit at my normal rev limit both times. i also had my nitrous set to run a little rich, like 10.5 afr rich.
I have sprayed pass the limit to 6774rpms while in gear & 7400ish between shiftsI wouldnt recommend it because of the momentary lean spike @6500ish when the ecu cuts fuel.
If grey could find out a way to install a fuel cut defender it could be possible.. I would just buy a jwt ecu(as stated above) or a standalone/ piggyback for safety reasons. If this were a stock 3.0 out of the junkyard or something I would say go for it.. But you have a lot of time put into the 3.5
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Old 12-28-2008, 03:16 PM
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Originally Posted by xlcrew View Post
grey just curious have you ever hit the rev limit while spraying before? if you have then i don't think you can over ride the rev limit by spraying extra fuel through the intake. i have hit the limiter on my 2000 twice while spraying and it hit at my normal rev limit both times. i also had my nitrous set to run a little rich, like 10.5 afr rich.
Nope - I've always used MSD 8969s for nitrous window switching, to prevent that very thing. I'm not surprised you couldn't spray through the limiter - remember you would have to provide all the fuel that the injectors normally spray to keep on going up in RPMs - more than a fuel 200-shot pill, I believe. If you use a 35-shot nitrous shot to atomize the fuel, then you need to jet for a 250-shot fuel jet. Scary, huh?
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Old 12-28-2008, 03:24 PM
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Originally Posted by accordingtou View Post
I have sprayed pass the limit to 6774rpms while in gear & 7400ish between shiftsI wouldnt recommend it because of the momentary lean spike @6500ish when the ecu cuts fuel.
If grey could find out a way to install a fuel cut defender it could be possible.. I would just buy a jwt ecu(as stated above) or a standalone/ piggyback for safety reasons. If this were a stock 3.0 out of the junkyard or something I would say go for it.. But you have a lot of time put into the 3.5
First I've gotta make sure that ignition spark is still there above cut - then set the fuel jet for 200-shot and the MSD switch to start spray at 6500 and end at , say, 6800 and give it a try. This way there will be a narrow 300 RPM "window of death" to worry about..

It's better to experiment with this engine than the new one in the chute. After looking at PLX logs from the last outing, I was spraying a 175-shot with not enough fuel and hitting better than 18:1 A/F through the quarter mile - and I just started it up for a warmup after sitting for three weeks in the ice, so I guess it's still OK.
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Old 12-28-2008, 03:47 PM
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hey gray why not unpug your nitrous niod set the msd to 6400 to 6800 and spray it in netural. this should answer your question

but if you want to confirm without doing that just ask dandymax for this extended rev limiter maps. this will let you know if he had to adjust the injector cycle or not
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Old 12-28-2008, 05:42 PM
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Originally Posted by t6378tp View Post
hey gray why not unpug your nitrous niod set the msd to 6400 to 6800 and spray it in netural. this should answer your question

but if you want to confirm without doing that just ask dandymax for this extended rev limiter maps. this will let you know if he had to adjust the injector cycle or not
Well, I think you gotta use some nitrous to keep from dribbling fuel all over the place - but yes, I'll have to think that one through - it would be quicker to do a test run while sitting in the driveway. If that works, then I'll take a drive to get A/F set closer. Good call ....

I had asked dandy about the injector timing after OEM fuel cut, but I don't remember that he ever answered that question. But - the EU injector timing would just replace the injector timing that just got cut off at 6550. Since I don't have any way to trigger the injectors after OEM fuel cut, I would need to spray. Besides, I want to see if it works.
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Old 12-28-2008, 06:03 PM
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Originally Posted by grey99max View Post
Well, I think you gotta use some nitrous to keep from dribbling fuel all over the place - but yes, I'll have to think that one through - it would be quicker to do a test run while sitting in the driveway. If that works, then I'll take a drive to get A/F set closer. Good call ....

I had asked dandy about the injector timing after OEM fuel cut, but I don't remember that he ever answered that question. But - the EU injector timing would just replace the injector timing that just got cut off at 6550. Since I don't have any way to trigger the injectors after OEM fuel cut, I would need to spray. Besides, I want to see if it works.
I meant ask him if he has to configure both the injector and ignition or just the injectors with the eu

cause if he has to configure both to go pass rev cut then you will know for a fact the spraying pass rev cut will not work

maybe someone with a eu will chime in, although I still vote for a jwt ecu with a extended rev limit and stock fuel and timing maps
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Old 12-28-2008, 06:10 PM
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3.0 and 3.5 flywheels

While the sun was out, I took a couple of shots of a 3.0 and 3.5 flywheel to show the differences. The 3.0 does not have a factory index hole with the crank - the 3.5 does have an index pin in the crank and a matching hole in the flywheel. I had drilled a hole in the 3.0 flywheel to mount it on the 3.5 engine I just stripped down - that's why you see one in these photos.


Side by side: 3.0 left, 3.5 right side:



3.0 one hundred eighty teeth:



3.5 three groups of ten timing teeth:



Well, now what? That's the question.....

.
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Old 12-28-2008, 06:14 PM
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Originally Posted by grey99max View Post
While the sun was out, I took a couple of shots of a 3.0 and 3.5 flywheel to show the differences. The 3.0 does not have a factory index hole with the crank - the 3.5 does have an index pin in the crank and a matching hole in the flywheel. I had drilled a hole in the 3.0 flywheel to mount it on the 3.5 engine I just stripped down - that's why you see one in these photos.

Well, now what? That's the question.....

.
If you need any extra, I've got one VQ30 and a couple VQ35 timing rings
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Old 12-28-2008, 06:17 PM
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Originally Posted by t6378tp View Post
I meant ask him if he has to configure both the injector and ignition or just the injectors with the eu

cause if he has to configure both to go pass rev cut then you will know for a fact the spraying pass rev cut will not work

maybe someone with a eu will chime in, although I still vote for a jwt ecu with a extended rev limit and stock fuel and timing maps
From what I've read, ignition is just fine up until ~8000 RPM, but looks like search is broken (again) so I can't pull up the old thread.

Wait, here it is:
Originally Posted by nismology View Post
It's not that the ECU can't "read" over 8000 RPM per se. It's that the stock ignition map stops around 82xx RPM.
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Old 12-28-2008, 06:40 PM
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It slipped my mind for a sec but meximax did something similar to work around the ring sensor issue.
http://forums.maxima.org/6140311-post6.html

Another member had one made from scratch too I just forget who
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Old 12-28-2008, 06:54 PM
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Originally Posted by t6378tp View Post
I meant ask him if he has to configure both the injector and ignition or just the injectors with the eu
No, the stock ECU makes spark out to 8,000 RPMs according to local gurus.
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Old 12-28-2008, 06:59 PM
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Originally Posted by accordingtou View Post
It slipped my mind for a sec but meximax did something similar to work around the ring sensor issue.
http://forums.maxima.org/6140311-post6.html

Another member had one made from scratch too I just forget who
Meximax grafted a 3.0 timing ring on his 3.5 manual flywheel - remarkable piece of work, but it's still just a 3.0 timing ring. A UTEC won't work with that.
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Old 12-28-2008, 07:08 PM
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Originally Posted by pmohr View Post
If you need any extra, I've got one VQ30 and a couple VQ35 timing rings
Thanks, but right now I don't know what to do with the ones I have now.....
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Old 12-28-2008, 07:39 PM
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The stock ignition map has a timing spike right around 6550. It spikes about 5-6 degrees IIRC.

Also, this is the max as far as I know the ignition map goes:


I do not recommend anyone else trying lol
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Old 12-29-2008, 09:20 AM
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Originally Posted by Kevlo911 View Post
The stock ignition map has a timing spike right around 6550. It spikes about 5-6 degrees IIRC.

I do not recommend anyone else trying lol
OK for the graph - lots of pretty colors, too.... EDIT: OK, OK, I don't know what most of the lines really mean.....

Does anyone know if there are ANY stock ECU injector pulses after 6550 ??? It might be easier to stretch the pulses if they are there in any form.

"I do not recommend anyone else trying lol" - no guts no glory...... If you ain't breakin' sumthin, you ain't racin.....


EDIT Again: I found the reason that the UTEC will not work off a 3.0 flywheel - in the 2005 350Z FSM Section EC, page 312, that page shows that the flywheel POS sensor AND both Camshaft position sensors - PHASE bank 1 and bank 2 - are required.

Oh well for the UTEC idea.

.

Last edited by grey99max; 12-29-2008 at 01:29 PM.
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Old 12-29-2008, 01:48 PM
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The stock ECU pulses 1.2ms of fuel at the rev limit.

Here is how it looks.


The red vertical line is before I bypassed the stock limit as you can see. The input duration is about 13ms and the blue vertical line shows after the revlimit. The input now is 1.2ms. The input is what the EU recieves from the ECU. You have to add roughly 10-12ms of "fuel" at around 6350-6450 to you can bypass the revlimit smoothly.
You can also see the timing spike in the graph.

And don't worry, most of these numbers are pretune...
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Old 12-29-2008, 02:37 PM
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Originally Posted by Kevlo911 View Post
The stock ECU pulses 1.2ms of fuel at the rev limit.

Here is how it looks.


The red vertical line is before I bypassed the stock limit as you can see. The input duration is about 13ms and the blue vertical line shows after the revlimit. The input now is 1.2ms. The input is what the EU recieves from the ECU. You have to add roughly 10-12ms of "fuel" at around 6350-6450 to you can bypass the revlimit smoothly.
You can also see the timing spike in the graph.

And don't worry, most of these numbers are pretune...
Interesting.. so the injector pulse gets much shorter at fuel-cut, but the pulses are still there.... hummmm... does your EU add a fixed amount of ms to each pulse as rpms increase? or does the additional added-ms continue to change higher up?
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Old 12-29-2008, 03:02 PM
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I have set to add w/e at the given rpm on the scale.

That is my map for bypassing the stock rev limit. The key is to get it really rich really fast to override the stock limit and then go back to w/e afr you want. This is an old map, I have fined tuned it more with different rpms at redline but you get the idea.

I have a 3" maf so I had to tune for all throttle ranges...
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