2/19/10 Edit: I went back to do some more dyno tuning at National Speed, Inc in Wilmington, NC. This time, my 128mph speed limiter was removed from my 02 Maxima AT ECM. I installed an 03 Maxima 6spd ECM, which I found out has a 145mph speed limiter (dyno proven). So I still was not able to max out 3rd gear. But my power is dropping off around the same time my speed limiter kicks in, so it's not a big deal.

We were finally able to tinker with the ignition timing. We found out that between 3500-4500rpm, the engine put down as much as 18 ft-lbs of torque MORE by retarding the timing by 4-5 degrees. I had it set around 29 degrees in this area before and the engine responded well to dropping the timing. Also, on top end, I had the timing set around 28-33 degrees. When we retarded the timing down to around 26 degrees, the engine did not loose any HP. So we kept the timing lowered.



Also, uncorrected, it put down 290whp!


-------------------------

This is the first dyno since I finished the engine swap. It made 271whp and still climbing strong when the stock speed limiter kicked in around 130mph. With STD, it's making 278whp and 251ft-lbs.

I will be using a 6spd 03 Maxima ECU and that should solve my speed limiter issues on the dyno. I can't wait to find out what kind of power this engine can really lay down, especially when the engine tune is to my liking. We haven't completely tuned for the absolute best ignition timing.

I still don't know how high this engine is producing significant HP.



Edit: Here is a 2nd gear dyno run that I did during the Dyno Day on Saturday. The HP will be lower in 2nd gear. The signal cut out during the run, but at least it gives me an idea of how much power I'm making at 7200rpm when the UTEC's rev limiter kicked in. For my next dyno session, I will extend the rev limiter.

I included the same 3rd gear run you see above so you can compare.



Edit again: Here is a good comparison of how my engine reacts to the cutout being open. An instant 20hp!



Edit again: Here is the video.
http://www.youtube.com/watch?v=Of39Ck6gLqA

 

It just wants to keep going!! lol It can rev to 7200 correct?

 

impressive

 

That power just keeps on climbing!

Didn't you try to dyno it in 2nd gear? If so, I'm sure the numbers were inflated, but I'd really like to see what the graph looks like all the way to 7200.

 

2nd gear shouldn't change anything, the dyno operator can usually correct for different ratios. That engine is making great power with just a lil less tq than I would expect for a 3.5l

 

The numbers would be inflated, if the dyno operator doesn't correct them. He should be able to rev it all the way to 7200 in 2nd gear...

 

What's your AFR look like? Ignition timing? Cam specs?

 

Very nice Aaron. Thats just where I thought you'd be. Your torque seems a little low though. Usually torque on our motors are very close to the HP number.

 

Well yes if the operator can't do his job you will not get the correct numbers..

 

Impressive numbers Aaron, hard work pays off. I dont think those numbers are inflated considering the work you have put into this built motor. Did you dyno with the TC locked or unlocked?

Why would you want to dyno in 2nd gear? 3rd gear would give you the most accurate HP/TQ numbers.

 

good job man

 

I know 3rd gear is closest to 1:1 and will give the most accurate numbers. Currently, it can only rev to 6300 in 3rd gear because of the 130mph speed limiter. He could rev it out to 7200 (or higher), if he were to dyno it in 2nd gear. Dynoing in 2nd gear would give a better indication of what rpm this motor is making peak power.

 

Those are some good numbers Aaron!

With tuning you will surely see improvements...

Maybe with a 3inch exhaust and cams I can get close to those hp numbers...

I need to shed some serious pounds to come even close to your car weight though...

 

Thanks everyone!

I have the rev limiter set to 7200 at the moment. But as soon as I solve my speed limiter issue, I may need a higher rev limiter to take advantage of all the top end power I'm making. I built the engine to easily handle over 7500rpm if I need to rev it that high.

We did one pull in 2nd gear just to determine if it was a speed limiter related issue or some weird rev limiter issue that was only lower on the dyno. It was a speed limiter issue for sure. That one 2nd gear pull we did lost the signal after 5K. But the only reason we did it was to make sure 2nd gear would rev to 7200rpm as it should.

AFR is a smooth 12.8-13.0:1. Ignition timing goes as high as 31 degrees on top end. Deluboz cams. The rest of my modifications are shown here:
http://www.nwpengineering.com/mods.html

The TC was locked on all runs. With it unlocked, the power isn't as smooth and tends to spike on low end when you first go WOT.

The cutout produces 20hp though when it's open. I do have the stock and very restrictive muffler and Bpipe. I like being quiet on the street.

 

Yeah cutout is always going to be a huge plus (20hp) on the flip of a button is awesome!

Good that you had TC locked that means ur numbers are even more accurate. I remember when I unlocked mine on a dyno it showed about 15% less power, but thats ofcourse because of the change in gearing n such..

Good stuff man, I am very interested to see your nitrous numbers now!!!!! That should take care of the lack in torque

 

Yeah. The way I look at it is that I have way more torque than most other VQ35s. Look how linear the torque is starting at the 4K rpm mark. I knew I wasn't going to have much low end power with this build. But look how much torque I'm making above 6K. Most other dyno charts for the VQ35 show the torque falling flat on it's face on top end.

 

Awesome numbers!!!

 

congrats, can you just cut a wire to remove the speed limiter like the 4gen gxe guys do

 

I haven't tried. Regardless, the 6spd ECU is going to be installed in order to fix my cruise control. If I ever run into that speed limiter, then I'll worry about it then.

I haven't found any concrete information yet. But right now, it appears that a 2003 Maxima SE 6spd with 17" wheels and LSD had the highest speed limiter (149mph or so) or none at all. That's the ECU I have waiting to go in. With a 149mph limiter, I should be ok until I'm ready to do low/mid 10s on 22" slicks.

 

I have a strange feeling that my car does not have a speed limiter at 149mph. If you do hit a limiter that fast, you would probably also be upgrading to bigger tires to make 3rd longer, which would probably throw off your speedo and let you reach higher speeds, anyway.

 

There has to be a simple fix for the limiter, although I have never messed with that, oddly enough mine dosnt have a limiter I dont think, i have maxed out the speedo and no limiter, I dont even think 97 GLE is supposed to have an extended/removed limiter. So im sure its not something hard to do, cut wire or some simple thing.

 

very nice numbers! cant wait to see what numbers you put going to 7200

 

Yeah. Some 5.5 gens don't seem to have a speed limiter, even above 150mph.

But instead of changing my slick size, I will just remove the speed limiter if the one on the 6spd ECU ever becomes a problem for me. There are ways to remove it, Technosquare can I'm sure. And I may be able to just trick the ECU and prevent a speed signal from going to the ECU from the cluster.

Yeah. My 92 Maxima never had a speed limiter of any sort. But I'm sure there is a way I can remove it myself if it ever becomes a problem.

I may be making gobs of power at 7200 as well. That's why I built up the valvetrain. If I need to rev to 7700, I will.

 

Yeah from the look of that curve, you may be making peak power around 6700-7000. That's interesting for those somewhat mild cams, but your IM/head porting has probably gone a long way towards shaping the curve for topend.

 

Yeah, it definitely appears the headwork went a long ways. I don't remember other SSIM/mild cam setups making peak HP this high. But I can't speculate too much more since I have no clue how much higher the HP will rise when I am able to rev higher.

I hope to get my 6spd ECU installed tomorrow at the dealership. They will be able to reprogram my NATS. And I might as well get a new key made ($80 OUCH!).

Does anybody know if the dealership will be able to easily see if there is a speed limiter on the ECU?

 

Here is a 2nd gear dyno run that I did during the Dyno Day on Saturday. I edited the original post to include this chart.

The HP will be lower in 2nd gear. The signal cut out during the run, but at least it gives me an idea of how much power I'm making at 7200rpm when the UTEC's rev limiter kicked in. For my next dyno session, I will extend the rev limiter further. There was no reason to extend it during the 3rd gear passes due to the governor.

I included the same 3rd gear run you see above so you can compare.

From 6300rpm to 7100rpm, it only drops by 4HP!

 

Man that's looking really flat. I bet you will be shifting later!

 

Great numbers Aaron That thing is going to be a BEAST up top. I don't recall what cams you went with?

I'd love to see the #'s on a 5mt :P

 

Yeah. I'm shifting at 7200 right now and that's way too early. I don't know my optimal shift point just yet, but in the meantime, I'll shift at 7500 rpm. And that still may be too early.

I have a very mild setup with the Deluboz cams.

 

Here is a good comparison of how my engine reacts to the cutout being open. An instant 20hp!

 

http://www.youtube.com/watch?v=Of39Ck6gLqA

 

W.e.a.k.s.a.u.c.e.

Damn VE traitor.

oh wait.. I drive a VQ35 too. At least mine drives the proper wheels tho.

 

Haha! Yeah I know. But I plan on sticking with the 3rd gen for as long as I can.

 

I still have mine. I just don't drive it anymore. I fired it up and drove it around the block the other day. "WOAH!" The way that VE is tuned, it's either on or off. spin the tires or nothing. with the stiff suspension and monster brakes on it, it's a bear to drive. forgot how much fun it was!

 

Time to get it back out on the track!

 

I went back to do some more dyno tuning at National Speed, Inc in Wilmington, NC. This time, my 128mph speed limiter was removed from my 02 Maxima AT ECM. I installed an 03 Maxima 6spd ECM, which I found out has a 145mph speed limiter (dyno proven). So I still was not able to max out 3rd gear. But my power is dropping off around the same time my speed limiter kicks in, so it's not a big deal.

We were finally able to tinker with the ignition timing. We found out that between 3500-4500rpm, the engine put down as much as 18 ft-lbs of torque MORE by retarding the timing by 4-5 degrees. I had it set around 29 degrees in this area before and the engine responded well to dropping the timing. Also, on top end, I had the timing set around 28-33 degrees. When we retarded the timing down to around 26 degrees, the engine did not loose any HP. So we kept the timing lowered.



Also, uncorrected, it put down 290whp!

 

Very very nice, I love how the power stays up there after it peaks. Question, was your tuning device picking up any knock at all? Usually you stop advancing time when your power drops or when it starts to knock, so if you gained power/torque by retarding the timing that means you were very near or right on that limit where it should be knocking.

 

Nice job aaron.

Just a little bit more....LOL

 

No, I've seen reports like this on the Z forums as well. Aaron, like me, can advance timing up above 34 degrees and not see knock (at least up top) and 30ish degrees midrange. It seems, though, that most people make their best power with 23-26 degrees in midrange and 26-30 up top with a lot of breathing room for knock.

Aaron that is an awesome curve, kudoz!!!

 

Wow.... That is a nice power curve!! Is your rev limiter at 7.5k?