Finished doing the 00VI swap a week or so back and hit the track this weekend. Im using (all 2000 parts: UIM, LIM, fuel rail, & injectors, rear valve cover and 3 rear coils).

I wanted to do runs with the 00VI UIM and test the difference with it in normal position ( for lack of better term) and with it tied open. I never physically tied it open but when i tested the UIM for top end. I connected a hose to #3 and ran it to #4 in (photo below). #2 was open and #1 was plugged.



With my old setup and same sixty foots with USIM my times were 14.1 to 13.8 and my traps were 97 mph to 99 mph.

Run #1: (top end)
On this run I connected the hoses like stated above for top end power. Picked up my timeslip and could not believe how slow I was, and 93 mph ? I was seriously confused on the whole top power end thing? Ran .3-.4 slower and mph was 5-6 mph slower ?

60: 2.119
1/8: 9.244
1/8 mph: 76.00
1/4: 14.461
1/4 mph: 93.77

Run #2: (low end)
On run number two I swapped the hoses, blocking off #4 and running with #2 and #3 open and #1 blocked off. What the heck does the #1 nipple do ? Anyways interesting results. I was .1 faster but only because my 60 foot was .1 quicker. And had same trap speed ?

60: 2.025
1/8: 9.132
1/8 mph: 75.49
1/4: 14.371
1/4 mph: 93.38

Run #3: (top end)
On run 3 I went back to the top end power setup convinced that the maxima felt faster but not showing it on paper. Also a bit disappointed with my previous 2 runs thinking I would still be around the same speed & (e.t.). Set it all up and gave it another try. Results still no good.

60: 1.987
1/8: 9.063
1/8 mph:76.02
1/4: 14.238
1/4 mph: 94.89

Run#4 (top end)
Well by now I could see that with same 60 foots my traps were way down from the 97-99 mph range and my e.t. were also slower. Another key note is that the temperture was only 3 degrees higher. And all runs on same track as with USIM.

60: 2.022
1/8: 9.031
1/8 mph:76.88
1/4: 14.183 best run of day
1/4 mph: 95.02

I suppose my main questions are:

1. Did I ever have the OOVI open? Maybe I should have physically opened it.
2. With the 2000 injectors will a rich condition effect your mph and e.t. this badly ?
3. My intake doesnt growl anymore like with the USIM setup, with that setup it would blow an eardrum with 00VI setup I cant hear it, only exhaust. I also hear a whistle like someone blowing in a glass coke bottle. that type of whistle but dont hear it at wot.

Any ideas, theories, opinions and conversation is more than welcome. Im hoping that its just that im running rich and that is the cause of the loss of hp. And a much slower maxima.

Also curious as to if I ever actually had the 00Vi tied open ( creating the vacuum source as explained above). The max did feel different swapping it but still unsure.

thanks in advance
ceasar

It's a start man.

What was the weather like the previous time you were at the track and what was the weather like this time? Richness will cause a little HP loss but not 3-4mph worth.

why the heck are you running with the 00VI tied open in the first place? do you not have an rpm switch yet or something?

yeah i dont have anything to activate it, the temp was 3 degrees warmer. neal on another note, all my buddies cars were running exactly the same times, and I was the only one down on mph and slower et's.

man i dont know where to start on if i have some other problems or not? im just about ready to go in for my tune (greddy emanage ultimate) and dont know if it would be a good move to fork out all the money, in NZ it will be at least 1 grand. maybe i should try and see if something else is wrong and fix it before going in for a tune.

only other thing i can think of is that we pulled out all the egr stuff and blocked it off and the evap canister purge control valve was pulled as well along with cruise control.

Didn't you just replace your tranny? New clutch?

no, same setup, shes old but holding, you see that 1.9 60 foot up there ?

Interesting. Just like Zack said its a start. I wouldn't be disappointed yet b/c your untuned. Having a functional VIAS is important to your 1/4 mile times. Also, I would say running rich definitely has an affect on HP. I did my dyno last October and every time we did a run we had to lean it out to get at least 8 hp.

I guess you can treat this as a base run before the tune but don't give up. In the interim maybe its a good idea to run a window switch to control your VI.

you need to get the VI functioning properly or your mph will be off, the track bug started itching you and you had to go, but you should have waited till everything was functioning. Also, changing injectors with no tune will hurt WOT performance. The weather also greatly affects trap speed.

After reading your other post (read what gtr rider posted), the way you were tying it open sounds like you had it running opposite from what it is supposed to be. Just hooking a vacuum line up to the VI nipple would have it open at lower rpm when the engine is creating vacuum, but with high rpm you would lose vacuum and it is closing at WOT. You have to either have a rpm switch, or you physically have to tie it open. hooking straight vacuum to the nipple functions backwards.

Yeah man I say the same You need to get the vias working for it to help. Also the car should be running pretty rich. Just think Nissan sets their ecus up to run about 12.3-12.5 WOt stock. You are running just a tiny im mean tiny bit larger injector. So I would say your air fuel at WOT is around 12.0. Thats what mine showed on my wideband before I started tuning

96sleeper, will have to read that again, but honestly I think you are on to something. while the car did feel different going from these two setups the mph was no different on avg. i just dont think i ever had it in the (using the term) tied open position. which probably means my findings could be false.

what i will try is to physically tie it open and see how that feels.

as for as tuning, you guys think i shouldnt worry about this and just go in and have it done soon ?

edit: was also wondering if anyone has even went to the track to test the 00VI like I did with my present setup? Total redneck theory here but I very well could have been using the low end setup all day, and perhaps USIM flows better through the 1/4 mile than 00VI setup for low end only. This mixed with running rich might be what was going on. will physically tie this thing open today and check out the difference.

main question here is how to setup the vias ? from reading i should block off #2 and just leave #'s 1-3 open. Sound right ?

either take the IM rod out or use a rpm switch. any other way will hurt your times.

ive tried some of the things your doing and awful times result

thanks krismax, well i went and tied it open (physically) today with a cable tie. and im not the best person to decide on how (seat of your pants runs feel). i never feel any difference reallly. left all 3 nipples open and plugged #4 ontop of the UIM.

but my initial reaction was that the car felt stronger up top, not crapping out as much to 6500 rpms. As the rpms approached 6250 -6500 it did start to feel like it was slowing down a bit, but not like usim does. Not sure what i was expecting it to feel like, I didnt scream out and start going nuts about it. However the car felt strong, but not throw you back in your seat til 6500 rpms. Maybe some midrange loss.

Cut the cable tie off, and tried again and more runs. I couldnt tell a huge difference with it like this, but from 5200 onwards to 6500 it did seem to be slower and not breathing as well. Giving you this, its working like a dog to produce any power.

After testing both ways I would have chosen to run it at the track tied open, overall it just seemed to have more power to redline, but again not like an insanely huge difference.

conclusion: i mainly dont want to have a load of misinformation in this thread from all this, I believe it has more power in the high rpm range, but it wasnt heaps more, just pulled better. going to take krismax advice and call it a day on this. without a dyno and two runs, its only guesswork. will just leave it be and prepare for greddy eu tuning. will go out and check the codes again and see what the ecu is saying.

question: if anyone has tried this, did cable tieing it open feel ***** to the walls faster, or just smoother and better to redline ?

You arent going to notice some instant vtec with this mod if thats what you are thinking.. The power is going to be seamless throughout the power band giving you sufficiently higher low end power with most of the change happening up in the higher RPM range where the USIM fell flat on its face.

I also notice that if I dump WOT it feels a lot more sluggish(my dad also noticed it from the pass seat) then just 3/4 throttle.

very well put, that describes what it was like. when i tied it open today the car felt better than both setups i was running at the track. it doesnt fall flat on its face up at high but keeps on trucking so to speak, but not in a vtec sort of way like you mentioned. we have a 97 pulsar with neo vvl (nissans version of vtec. when that kicks in you are very aware that the car has seriously more power all of a sudden. even though it is a much slower car than my maxima.

was looking at my best at the track
13.8@98.8 USIM
14.1@95 00VI

i think everything is ok after posting up on the boards. My half wit runs with 00vi upper and running a bit rich probably sums my day of racing. going to move on to the next phase. install and tune of EU. Dandymax is passing through my way in about 2 weeks, will be good to chat with him about it as well.

oh my, all that smoke at the front of your car. might you perhpas have an exhaust leak j/k lol. I always admired your car and envied your timeslips.

Just as a point of reference, my old 3.0 before tuning was 184WHP-189WTQ. After ONLY SAFC1 tuning taking it from 12.0-11.9:1 up to 13.5:1, came up to 191WHP-195WTQ (difference of 7WHP and 6WTQ). This was on stock 259cc injectors, so chances are, you're running even richer than I was since you now have 290cc. So you are bound to gain AT LEAST what I gained - this is from a/f tuning ALONE btw, who knows how much more you can squeeze out with advancing the timing.

Dont feel down right now, your car now with VI and soon to be EU-tuned has PLENTY of potential left in it.

i think the problem has been seen here, running rich, switchover just not happening. you might think that being WOT having all top-end would be good, but since the low end suffers so much when the VI is tied open, you still wont see nearly the times that you will when its a working VIAS.

Just get that VIAS operational and go back, even without a tune youll probly be around your old numbers if not better.

videos:

(A32) 97 Maxima vs (ek9) 97ish Honda Civic Type R


(A32) 97 Maxima vs (dc2) 97 Honda Integra Type R

with 00 injectors and non working vias, your car is probably slower than USIM. Once you get a working vias with it properly switching open at the proper RPM, and some tuning, maybe not even have to wait for a EU, just by adjusting fuel pressure you can lean it out a bit. with your car tuned and a working vias, its a huge difference, you will defenetly shatter your old record. Wether you leave it tied open or closed, your still going to get a slow time. You either lack low end, or top end. so your not really getting anything out of the VI, once u have it switching over automatically lets say at 5200. your going to have a smile on ur face. So keep working on it dude. I believe i improved either .3 or .4 from doing 00vi (when i was on nitrous).

wanted to post up this chart, never know who may be looking for information. will be interesting to compare this data with the setup tuned and some track runs in the future.

Caesar, glad to see your car running on a VI, finally.

I have a few points to make here...

Connect nipples 3 to 4 will yield the following results:

1) Car at idle, AND AT REST, you can rev all you want, your VI will stay open because your manifold vacuum is highly negative, and while revving in this idle mode, you will not see your VI closing at all, because it doesn't stay on reving that long. You may see it closing a couple times when you back out from throttle a little bit.
2) 1st gear and 2nd gear driving, your VI will stay open and probably stay open all the way like case @1 when car isn't moving, but at the ending rpms of 2nd gear, you'll probably experience it closing momentarily, I am pretty sure of that.
3) On third gear, you drive across the rpms, and I can vouch that your VI is pretty much reaching irratic opening and closing states. Especially towards the end of theses rpms, I am sure your VI is closed.

The reason is simple, your intake manifold, while natually aspirated, depends on this highly negative vacuum to "suck" air in. While the car is at rest, then 1st gear, then 2nd gear, your manifold pressure vacuum stays highly negative and are barely violating the needed vacuum pressure to keep the actuator switch opening. That's because all these entire rpm intervals are driven across very quickly, engaged time-wise.
When you get on 3rd gear, which takes up slightly more than half of the qt, your manifold vacuum pressure becomes less negative, reaching towards atmos pressure because the throttle is opened for so long. The only reason for air to still roam in is the 1) pistons moving up and down draggin in air and 2) the air movement itself creates a momentum moving in a supposed organized manner in and out of the motor. At this time, your throttle is opened for so long that your air front is pretty much at the head valves, though still moving very quickly. But air front at the head valves means your manifold pressure is closing in to the equilibrium of atmospheric pressure. At this stage of your quartermile, your VI actuator will not have enough vacuum to keep itself "sucked" open, thus closing the VI and killing your high ends. I'm pretty sure you're feeling the top ends from this 3-4 nipple setup simply from the 1st and 2nd gear, but on 3rd, I'm proposing that you're losing power half way towards the end, killing your trap and qt.

You can do an experiment like this: Connect nipples 3 and 4, keep the hood open so you can see the VI switch inside the car, turn car on, at rest, rev it and hold it at 5k rpms. Initially, you'll see it open, but at one point when its vacuum drops below the threshhold, it'll close, especially if you just back down the throttle a little bit. This is all from the air dynamics. It's easier to picture it as an air front location. The further it reaches into your head valves, the more your manifold reaches the atmospheric pressure, closing the VI switch. The only way for this 3-4 nipple method to work without closing the VI is if you can drive across your entire 3rd gear rpms as quickly as you'd drive across your 1st gear rpms, which in our N/A: not possible. Basically, the quicker your rev across the rpms, the less a chance your air front reaches your head valves to decrease the vacuum.

All this vacuum talk I got is based on relative pressure of the vq30de motors. I am not saying that the manifold pressure reaches 0 with with atmos at all, I'm saying as you drive across your rpms, you'd experience that negative pressure to come to atmospheric. But since you can rev across resting, 1st, and 2nd gear rather quickly, that gives the motor less time to reach towards atmos, but on 3rd gear, it's just long enough for VI to drop below the thresh-hold supply of vacuum to finally close it. The logic is all there.
Your only solution, like many others said above my post, is to get the rpm switch, vacuum bottle and get it to function properly. Sorry for the long post. Hope all this helps.

-Peter-

Everything has pretty much been said already but i'd just like to add that a non-operating 00VI is worse up top than the USIM.

godfather you rule for a long and intellectual post. cheers.

nismology - i also agree, and I think from my day out at the drags i have proved that with my car.

next test will be with it working