96sleeper

iTrader: (4)

We did the install today, and got it all done pretty easily in about 5 hours including making a custom bracket, cleaning the lower manifold and a trip to Lowe's for some brass fittings. Everything was pretty straight forward, with no major problems. Thanks to my friends Andy and Joe for the help, never would have gotten in done so easily. Only problem is that my RPM switch might be malfunctioning like a few others. It worked right away when we hooked it up, but then after 4 or 5 openings it quits working until the car is restarted. The switch doesn't reset itself though, so I am not sure if my problem is the same as others. Dave? Neal? First impressions are very good though...I noticed it right away. It pulls so much harder up top now. Can't wait to get my car to the track. I will do some more testing tonight if I get a chance. My car spins into second very hard now, and I even hit the rev limiter one time. It used to just chirp on the gear change. Overall I am pretty happy with this mod so far.

Nealoc187

iTrader: (23)

After the first couple days, I haven't had a problem with my RPM switch. I think its been the same story with most people. A problem or two early and then it seems to work flawlessly...?

Glad you got it all installed, its fun isn't it

96sleeper

iTrader: (4)

you know..you are right, after the initial problems earlier today, my VI has worked flawlessly every single time this evening. And it is very nice, the pull in the top of second ( and third) is unreal. I am enjoying it very much.

j_bryan

iTrader: (1)

very cool! what RPM did you set your VI to open?

96sleeper

iTrader: (4)

Right now I am on the 4600 rpm bandwagon, but I will do some experimenting of my own, and I eventualy plan to dyno to find the optimal point for my car.

iansw

iTrader: (7)

On the 15 Dynos I have done, without (8 of them) and with (7) the SC, 5000 worked best each time.

If you do 4600, the hp/tq dips for a second at the switchover point (turbulence), and never comes back to full levels.

Same thing happens at 5500.....

It's really strange, but at 5000 it dips, but way less, and picks back up very quickly.

IanS

mtrai760

iTrader: (19)

I can't wait to get one... Congrats.

FAST LS1

We had a great time helping you put the VI on Matt. Now you have to go to the drag strip the next time I go

meccanoble

iTrader: (22)

wow u can actually choose when you want it to open?! I know i'm going to sound a little stupid but if u can actually pick when, why doesn't everyone select theres to open at like .5 or 1?

BSwithTF

iTrader: (8)

Now you go and install a VI. Damn you! j/k I had mine set at 4600 last night when I ran my 15.01. Set at 5k it always seemed to hesitate for a minute right around 4k and then it would start climbing again. I should be getting it on the dyno in Oct. sometime so maybe I'll be able to play with it.

iansw

iTrader: (7)

Don't worry. It's OK. you always sound stupid

Seriously, if you open it anywhere below 4k, the resonant length of the plenums is wrong for the amount of air your pushing, and you lose hp and tq.

Through long tested experience (I was the first one to get a VIAS on a NA car - Thus "Club Member #1), I have found that 5k is the best....even so much to say as it's better than 4900 and 5100RPM.

I would love to see however, other people's data. I'm always open for ideas.

So go Dyno that puppy!

IanS

Nealoc187

iTrader: (23)

You only want short runners at high RPM, at low RPM you want long runners. When the vi "opens" it makes the runners effectively "shorter". If you were to switch to the short runners at 1000rpm for instance, you'd probably lose about 40 ft-lb of torque from 1000 all the way up to about 4500-5000, at which time you'd start seeing the advantage of the VI over the stock intake manifold. Basically it would feel like a small engine with alot of top end... sort of RSX-ish.

Toolrocks

iTrader: (1)

I don't think the VI design on our cars lengthens the runners. I haven't gotten mine yet but from the pics and seeing Speedtrips in person, I am of the thinking that the VI uses the butterfly valves to open up access to a resonance tunning chamber. I am applying what I read in September's Sport Compact Car. It's a very interesting article that starts on page 276. Happy reading.

iansw

iTrader: (7)

I think you're right. I edited my post. It all has to do with resonance.

IanS

Nealoc187

iTrader: (23)

The runners don't physically change length in our MEVI design, but the same principles apply. Too short a runner or "effective" runner will kill low end torque. Some cars have true dual runners, like SHOs, Integra GSRs and Prelude VTECs, etc.

Bags

iTrader: (3)

congrats

I would like to see your dyno and track numbers

get to the dyno and find your best switch over then go to the track.

I am in the same boat after day 2 my RPM switch was great no problems. where is yours located? mine is in the engine bay

Mr Cranman

iTrader: (1)

I'm glad you were able to get on and working with no problems...except that little RPM switch deal that fixed itself. Come to think of it I might of had the same problem...but can't recall. But, glad to see your enjoying it. Can't wait till you get your track times.

Have a great week,
John

SHODOG220

What do you mean by "true dual" runners? Do you mean 2 stages that are both equal length? cause if so, that is TOTALLY untrue. That would completely defeat the purpose of a dual stage intake. SHO's have 2 different lengths of runners just like the ones being described throughout this thread: short runners for high end, long runners for low end.

SHODOG220

WHOA! Dude, chill! Im sorry, I wasnt trying to be a smart *** I just misunderstood what you were trying to say. sheesh! Sorry if I ****ed you off man.

Nealoc187

iTrader: (23)

No, you misunderstood.

The SHO, Integra GSR, etc, have true dual runners which you and I both know are different length, long for low end and short for high end power.

The MEVI which is currently being put on 4th gen Maximas does NOT have true dual runners. It has single runners only, but a secondary plenum that WHEN ACTIVATED changes the resonance effect of the runners, extending the torque plateau some and resulting in a bit more high RPM power. The MEVI does NOT have 2 sets of runners, like the SHO and GSR.

EDIT: Crap, sorry bout that. I was hoping I deleted that before you saw it. I just got done studying for a test and I was in a crappy mood when I posted that. I deleted it as you can see and worded it more nicely because I shouldn't have snapped at you like that. Sorry man I apologize.

matty

iTrader: (54)

Well even though the MEVI is not true dual runners, its still good right ??

I ordered mine last week and im beginning to think I wasted my money..Whould 2 runners for the 4th gen be better then the MEVI ?? and will they ever come out with them ??

-matt

Mr Cranman

iTrader: (1)

Anyone that has a VIM can tell you that it isn't a waste of money. There isn't a dual runner application for the 4gen or any Maxima that I'm aware of. The VIM is kinda like a dual runner...just for the fact that the air resonance doesn't have to travel all the way back to the end of the runner when the vavles close...it just bounces off the top of the VIM. Therefore cutting down on the resonance and getting more air in the cylinders at the higher RPMs. You are definitely going to feel something with this mod. It isn't an UDP, or high flow cat...this is something your going to feel on the dyno-butt.

-John

drivinhard

The key on this is to tune them to the cams. Figure out where the cams want to make the most torque, and set your intake up to accent them in that range, you'll get excellent cylinder fill and make a bunch of power.

One thing that's easy to do if you are only dealing with either 2 runners or a switch on your intake (ie a 2 position setting) is to dyno the car with it on all the time, and off all the time, and pick the point in the torque curve on the 2 graphs where they intersect. You'll find the where each set-up makes it's torque, and best where to cross them.

On my 89 SHO I get as much as 12 ft/lbs in a few hundred rpm range by switching to the shorter runners a few hundred rpm sooner.

mark
92 SHO - 14.70 @ 95.4 mostly stock
89 SHO - 13.93 @ 99.7 all motor 12.92 @ 108.9 on the bottle

SHODOG220

Aint no thang man. BTW, your Maxima is SWEET! Im going to go look at a Black/Black 99 SE-L 5spd today. I cant afford it but if I could, I assure you it'd be in my driveway tonight!