MEVI currently opens at 5100rpm What should I set it too based on the dyno? 5000rpm?

Blue = MEVI, Red/Green = mevi not activating runs



Video http://www.youtube.com/watch?v=QhzLHdds3nI

 

So it looks like your making 153 whp. what's the torque in ft-lb. I woulds say your running a little rich after 80 km/h. It should be closer to 13

 

doesn't look like it took away from low and mid range the mevi that is. just a dip and all high end powa

 

First dyno was with MEVI installed but not activating which might be why you can't see a potential difference in low/mid power.

I just upped the activation to 5300rpm and it does seem smoother engaging, I don't want to have dyno again to see if the dip is reduced but butt dyno says yes

Does anyone know how to convert my torque to ft-lbs?

 

I was thinking the same thing, until I myself. . .. . He's from NZ, he knows not of any USDM IM.

 

Sort of do.. NZ Maximas have the same USDM IM.. its just the Imported JDM Cefiro's that all have MEVI.. JDM Cefiro 161kws > NZ Maxima 145kws

 

based upon your dynos you should be activating the VI closer to 5450. The MEVI should open where those lines cross which is about 5450. So I'd move your activation up the at least 5400.

 

Weird seperation between RPM points on that graph. 5300RPM might do it for you but like hacim said try 5400ish and see if you notice a difference. Def needs to be higher than what is was on dyno. That little dip around 4200-4400 is only going to be fixed by timing advance unfortunately. Why didn't they rev it out to 6500?

 

I have set it to 5300rpm (approx, summit rpm hard to be exact)... if you listen to the video you to hear him bounce off the rev limiter so not sure why it comes up short

 

nice video

the air/fuel ratio must be between 12,5 and 13

 

You'd have to say that on stock ecu its sitting pretty close to optimal.. bout between 12 and 13.5 by my dodgy eyes. I have just cleaned my TB which seems to have made everything run more smoothly.. new exhaust tuesday so good excuse to dyno again Will do one pull at 5300rpm and 2nd at 5700rpm to where mevi opens best

 

..bump ..bump

Based on my dyno above.. would a V-SAFC be worth doing or no?

 

I'd say yes, you could gain.

 

Do it, no question about it, there is more power to be had from a/f tuning here

 

I don't think you're going to see much better gains out of an AFC. AFR isn't bad at all for the stock ECU, surprisingly. But hey VAFC2s can be had for under $200 shipped off ebay so if you want to mess with it go for it. But that means a dyno tune and more $

 

Thats what I wanted to hear

Going to dyno tomorrow .. new exhaust.. and corrected MEVI openning.. 120kws? Previous dyno stock exhaust+Y & bad mevi openning = 114kw.

Will see if they can give me an increase estimate based on the AF ratios

 

I might dyno tomorrow too

How are you planning on conditioning your AFR?

 

Do you mean how am I going to adjust Air Fuel ratios - eventually using Apexi S-AFC, V-AFC (which ever).. but tommorow I just want to get new dyno without the massive dip from VI activating and to see if new exhaust freed up some power. Then get them to tell me roughly how much they could gain me with an Apexi.

Local place has dyno day 1st sat of every month $US47 for mixture check and one power run pull.. going to ask if I can slip in a 2nd and try higher VI point too

 

well just for reference, on the 3.0 from tuning alone I went from 184WHP-187WTQ, to 191wph-195wtq. What those #s convert to in kws, I have no clue, lol.

Just for reference, my car ran a bit richer than yours. at 4500 (my richest point) I was at 11.9:1, the rest of the closed loop range (3k-redline) was mostly at 12.2:1.

Remember that not only does it help to make power by tuning the a/f, but it also makes the engine more responsive by doing so. I still love my SAFC.... but yea EVENTUALLY EU will replace it, lol

 

The reason a lot of these VQ's gain from tuning is the indirect timing affect.

These run rich, so that alone = gains, BUT, we also can add timing by taking out x% of fuel, effectively, adding timing to compound said gains

 

Thanks dude good to know