On a whim, I decided to lower my VI setting to 4700rpms instead of the orginial 5000rpm setting. I did this because of the potential "lag" in the intake air/resonance as the VI opens according to the dyno. I also felt the 5000rpm switch didn't feel "just right". By using 4700rpms, it seems as if the VQ accelerates even better. Everything feels more linear, especially when entering 3rd on the shift. I know the dyno graphs suggest that 5000rpms is probably the best setting for ultimate power, but it sure feels like 4700rpms might be the best setting for a 5 speed when racing. We'll see how my dyno goes.

I'd like to know your opinions if you try this setting.


Dave

 

I may try this setting and see how it works out. I'll let you know how it goes tomorrow.

 

Dave,

The lower RPM setting is a good call. I have tried 5000 rpm and also 5200 rpm... But 4700rpm definitely feels better than either. Much better... Maybe not in terms of power but in terms of smoothness. Something is a little unsettling about feeling the little blip at 5000 rpm (or more) when the VI activates. The VI activation is much less noticeable at 4700 rpm and then you just get silky smoothness up top that is oh so nice. Even if we do lose some power from 4700-5200 rpm, in terms of sheer driving feel, 4700 rpm is definitely a VERY good setting.

Thanks for the tip. I think I will leave it there. Doesn't the 3rd gen's variable intake switch over at 4700rpm too?

CW

 

i like 4800.

 

I'll play with mine when I get my car back, but I believe the VEs open up around ~3000 rather than a higher rpm.
-hype

 

If the track isn't too busy tomorrow I'll get in a bunch of runs and try a bunch of different settings and report how they pan out. Dave when are you dynoing and getting to the track?

 

4700 does seem a lot smoother and it just feels better. I think I will leave it at this setting for now as well and see how it goes.

 

I hope you get a bunch of runs in. I went to the track last night after work, BUT they were doing their annual "Fox Hunt" race at the track instead of Test-N-Tune. I could have raced, but it would have been bracket racing and I didn't need that kind of pressure when I'm tryin to relearn to drive my car. What really sucked was that is was in upper 70s and 30% humidity which is unheard of for Kansas City at this time of the year. I plan on going to the track next Wednesday night.

I'm looking to dyno in a few weeks.

Dave

 

yeah i heard you say that you wanted to go last night and i forgot to tell you about the fox hunt SORRY! its too bad you didnt get to run because its supposed to be back in the upper 90s all next week


Trevor

 

Everyone,

I just looked over Mr Cranman's dyno spreadsheet and it's apparent to me that we could lower our VI setting to 4600rpms and still be okay. Take a look:

http://www.vanillaice.com/webmasters/hype/mrc/mrcVI.xls

The difference in power between opening the VI at 5000 and 4600 is marginal and at most points, the 4600 setting is making more power than the 5000rpm setting. So, I'll probably go with the 4600 setting.


Dave

 

This might be a moronic question to all of you that have the MEVI and are familiar with but the hell with. Okay, here it goes.....why not activated at say 3k? More power earlier on? Kinda like VTech controller's do for Hondas.

 

The VI doesnt give you power all the time. It only gives you more power in high RPM environment. So is VTEC. If VTEC and VI helps out all the time, then honda and nissan would choose to leave them on all the time. hahaha.

 

Roger that!

 

I'll try some different settings and see what happens. Set at 5000, I hit consistent 15.1's (80-90 degree weather). I think it'll be cooler tonight.

 

I totally agree. Look at 4600 compared to, say 5100. The tiny amount of HP you lose at 4600 is more than made up for by the large amount of torque you gain around 5000...looking at the area under the HP curve between the 4600 and 5100 plots. I think I'll target 4600 rpms when my switch comes back (next week, hopefully).

 

When you guys say 4600rpm, are you taking into account the delay between the switch activation and the actual opening of the valves? Because in 3rd gear for instance there is about a 350rpm lag between when the switch activates and the valves opening.

BTW heading the the track in about 30 mins. Hoping to make some passes with different settings, as well as VI off to see how much its really giving me.

 

god I love you guys!! and I dont even know you... cant wait till' I get mine

 

Same here.