96_vqmax

iTrader: (16)

i have notice the sound of my Frankercar intake change after i install my VI,it sound like the mid pipe was removed,mine was auto.i am guessing that it was due to the butterfly not completely seal the uppuer chamber,so the intake is sucking some of the air from the upper chamber.that's why we all feel the lose of low end power and everyone can see it the dyno of the us vs mevi,or is it just that my max is not running in top condition.thanx!

Dave B

Your car is fine. The overall intake noise is much smoother and quieter than the USIM. I use to think that there was possibly some turbulent air forming between the butterflies and the intake runner, but I don't think that's the case after viewing my VI dyno graph. According to my graph, my VIM torque curve is as flat Kansas compared to the bumpy torque curve of the USIM. In my mind this means the VIM has a smoother flow than the USIM.

As for your loss in lowend power, that's what happens with the VIM. Since your torque curve has been smoothed out, you lost ~10-15fwtq and fwhp at certain points from 2500-4500rpms. Look at my homepage for my dyno comparison between the VIM vs the USIM to see how much power you lost in the lowend.


Dave

mzmtg

iTrader: (11)

No air actually passes through the upper chamber. It is only used as a closed resonating volume. So "butterflies not sealing" is not an issue. Also, the shape of the inside of the MEVI is different than the USIM, hence the different sounds.

mrb23

you sure your not leaking any air at the throttle body? My local dealer still out of stock on throttle body gaskets, but we used some sealant, and there was still some air leaking out of it. As for sounds, I just had it installed Saturday, and it's been raining ever since, so I can't really tell the diff yet with my PR CAI.

Dave B

How do you know you're leaking air? Could you feel it or hear it. You really should buy yourself a vacuum gauge because that will tell you if you have vacuum leak. If you had a vacuum leak, your idle would be low and your car would feel pretty weak at all rpms. If the leak is bad, the car won't run.


Dave

96_vqmax

iTrader: (16)

no,i dont think i am having air leak problem,my car would idle smoother than before after i install my VI,cause i clean out the lower plenum(carbon built up pretty bad)iacv and throttle body,the reason i post was because i want to see if everyone with auto feel the same low end lost i am feeling,but on the 1/4 mile i defenitly feel faster,before i install my VI (my car with y pipe,intake,and udp)my friend's Q45 would walk me after 60mph,now after i install VI i walk him to about 90 and at about 95 we were even.my next mod prolly be b pipe,2k muffler and jwt ecu,hopefully this will give me back some of the low end i lost,

96_vqmax

iTrader: (16)

Dave B can you give me more detail on where and how you test your vaccum(like which hose you disconnect),

96_vqmax

iTrader: (16)

i also found another problem when i install the VI,the evap canister purge volume control valve does not fit on my VI,the hose connect to the VI manifold is bigger than the pipe stick out (between the iacv and trottle body) it suppost to go on it,so i use a smaller hose clamp it to the VI and then stick the other side to the evap canister purge volume control valve and clamp it tight,do your think this will be fine since the volume is reduce in size?thank to all those reply.

99DustMagnet

My 99' I30 W/VI definitely felt a low-end loss. I haven't dyno'd it yet but you can feel it. Also,IMO the shift points are all messed up if you don't manually shift at the track with the VI. As most people with VI's, we need an extra 500rpm to see a big difference at the track.