Well I went to MIR today and got 3 runs in. I tried to spray, but the car didn't seem to like it, so I let off. My first run was my best, here's the breakdown:
60'- 2.19
1/8- 9.49 @ 74.31
1/4- 14.70 @ 95.48

Since my previous best time I have added the MEVI/JWT ECU, UDP, SPEC stage 2 clutch, and new spark plugs. I noticed that I only gained 21.1 MPH in the second 1/8th, which worries me since I was sometimes gaining that much without the MEVI/JWT.

For example, here is my previous best run from a year ago:
60'- 2.14
1/8- 9.54 @ 73.20
1/4- 14.84 @ 92.85

As you can see I am gaining a little more speed through the last 1/8 as of now, but not nearly as much as I was hoping to gain with the MEVI/JWT ECU. On my previous best, I gained 19.6 MPH, and today 21.1. On other runs in the past I sometimes gained 20-21 MPH, but those were rare and usually when I got a poor start.

On a side note, when I tried to spray it felt like it wasn't spraying as much up top as down low. I know this can be explained simply by saying there is twice as much air and fuel going to the engine at 7000 RPM than at 3500, but still, both myself and Tilley felt it didn't feel especially strong up top as it should. Also, when I tried to spray in 3rd, it felt like it bogged and didn't spray like it should. When driving NA, I didn't notice any real power loss up top, so I'm a tad worried/confused. I think it's time to dyno and see what's really happening.

Anyways...I don't know what advice you guys can give, but I wanted to post anyways.

Also, my slicks don't clear my calipers, and with the spacers on there isn't enough lug left. I bought the slicks/spacers off an org member, so I'm wondering how he used the setup since he said it should work with the spacers.

 

Is the ECU programmed to run with nitrous?

 

Yes, I have the JWT NA program and at the flick of a switch the JWT NOS 65 shot program....

 

And are you running a step colder plug?

 

I am sure you have check but did you check to make your nitrous bottle pressure was enough.Your 60ft times are excellent but your trap speed seems very High for your ET.
I may just be take a while shot in the dark but i would try to find out what the JWT NA program is for when you are off nitrous? Seem like maybe you just have an extended limit with stock tune in NA mode and then in spray mode you have the Juice?

more guys with stock Im and nos are running mid to hight 13's something is deff wrong.

 

No, I'm running OEM plats as per the recommendation of JWT, although I'm considering coppers now. JWT says I can run stock heat range since their tuning "takes care of it".

Bottle pressure was above 950 most of the day. The times I posted were NA, I didn't get in a good run with the nitrous. The NA program from JWT should include advanced timing and raised rev-limiter.

 

Hmmmm....Yhea, those traps are a little slow. What elevation is that track at and what was the temp?

I would go dyno to see what things look like. I was having some serious power losss issues up top and never knew until I got on the dyno. You should be able to find a place to do like 2 or three pulls without tuning for $70 or so.


Gaining 21mph in the second 1/8 is very normal with your set up. That is what I usually gained, sometimes a bit higher but 21mph is normal. I would say your previous expierence with gaining 20+mph with the stock intake manifold is freak occurance.

I would like to see the full slip if you don't mind posting the #'s. Good 60' though.

Getting a dyno will tell you alot. Besises that, a couple guesses are that maybe the ECU is not switching maps from Nitrous back NA...just a thought...but I would think the times would be worse if that was the case. MEVI activation problems. How heavy are the rims you were using?

Can't help on the nitrous stuff, sorry

I have gone through gettting bad times at the track so many times I know it can be frustrating but hang in there you will figure it out.

 

The track is MIR, which is think is pretty close to sealevel. It was about 50* with clear skies. My rims weigh under 17 pounds. Here's the full slip:
60'- 2.19
330- 6.21
1/8- 9.49 @ 74.31
1000- 12.33
1/4- 14.70 @ 95.48

Here is the only other NA run I got in, and I spun too much off the line. Notice the lower trap, and only gaining 20.4 MPH.....
60'- 2.30
330- 6.40
1/8- 9.75 @ 73.10
1000- 12.65
1/4- 15.06 @ 93.52

Mike- are those gunmetal gauge rings, or regular silver? They looks like mine...

I dunno, it just seems like the traps aren't where they should be, and with the 2.19 60', it seems like my et should have been lower as well. Dyno time for me....

 

Looks like your running slow through out the whole 1/4. Just did some time comparisons from old time slips (MEVI/JWT ECU). Now, this is not concrete since we are dealing with two different cars on two different tracks. But for the most part when I pull a sub 2.2 60' my 330 is almost a 5.9 or less. Also you are about .2 slower than I was from in the second 1/8. Compared to my slips you are .2 slower in the first 1/8 and .2 slower in the second 1/8 which tells me it is just lower power through the whole rpm band.

 

And that much less power seems to point to some fairly major power loss, since we have the same mods and very similar weight. What do you make of all this?

 

Man, it could be soo many things. Just as an example, I found one of my coil pack wires was almost non-existant and soldering it gave me 10hp through the whole rpm range. Not that I think that is your problem, just an example of little things that can be happening.

If I were to guess, it would be one of the following in no particular order.

MEVI activation problem

Slipping clutch

JWT ECU issue. Either no advanced ignition and AF ratio adjustments done the the NA map or the ECU is not switching over from the nitrous map and your running retarded timing and a richer AF ratio all the time.

A y-pipe flex section problem perhapse

a maintenace issue



But I would go dyno to see your AF ratio and how your power curve looks before making any assumptions

One other thing, something you probably don't want to hear, is some cars for what ever reason are faster than others. There is no reason to explain why Neal's car was a solid .4-.5 faster than mine when we had the same mods and pulled the same 60 foots. But I don't think that is it because what I ran with my MEVI JWT ECU combo is about average compared to others with that set up. Neal's car was just a freak.

 

What kind of activation switch are you using for your MEVI? I run 14.7@95s pretty consistently with stock ECU.

 

I'm using a Summit switch set at 5200, and as far as I can tell it's doing it's job. I don't think the clutch is slipping since it has 1300 miles on it, and I'm am finally able to chip second gear. When I tried to spray through 2nd, the clutch held, so I'm not gonna worry about that yet. I do notice some raspiness from the y-pipe when I let the engine decelerate itself, but that noise has always been there, but it's something to check.

How would I figure out if the JWT ECU is really doing it's job? JWT had it for 6 months, they better have done it right the first time. As far as maintainence, I just put in new plugs, oil, tranny oil, and in the last 2 years replaced KS, fuel filter, and all sorts of other things. And yes, my TB is clean

The thing that bothers me the most is that with the MEVI/JWT and UDP, at the same track with same conditions and similar 60', I was only able to cut off .15 and add about 2 mph. Maybe if I could get more than 2 runs in I could improve a bit...but I don't think that's the problem right now.

 

The AF ratio will be a dead give away on a dyno as to if JWT has ajusted it. Even though they had your ECU for 6 months, they probably spent a few hours of work on it total. They have these maps saved on computers, they just have to burn them on to a chip an solder in the daughterboards.

 

Oh, I know how little time they probably put into the ECU. Seeing as how a reprogram costs $100, and I doubt they pay their programmers less than $20/hour...so less than 5 hours for sure, although they tried to say "oh, it's too hard since we have to switch the nitrous parameters and such whine whine whine...."
I'm getting a comp check this week to help start eliminating problems. A dyno will be done when I get enough people together in the DC area, and it's not looking good.

 

I'd advise you to do a visual inspection to see when it is opening. I posted a thread in the 4th Gen forum about when I replaced my Summit switch, the yellow pot adjustment screw was way off with the same settings as my old one. My new switch opened at 6000 instead of 5200 so I had to back it down to 2200 for it to open at 5200.

When you said it seemed like the car running a bit slow when you sprayed, it sounded to me as if the A/F was way off.

 

Yeah, to get it to open at the correct rpm we had to adjust the little screw (which I think is what you're talking about). As far as I know you should be able to set it at 5200, and with enough adjustment get it to open then. Why do you have it set at 2200 for it to open at 5200?
Paul (requin6) did the install, and if I remember correctly we did do a few visual inspections to make sure the MEVI was opening, but we only could do this at idle. Is there any way to know if the MEVI is opening under load/when the car is moving?

Also- the WSP y pipe is over 3 years old. How long do these flex sections usually last?
I am at least sure the Summit is doing it's job since Paul hooked it up to the security light, so the red light lights up whenever the Summit does, but I guess that doesn't necessarily mean the MEVI always opens.

 

You need to see if it's working. I think you can honestly solve your issues with some Dyno tuning.... See how things are working and also do some analysis....

 

Wanna join the dyno group and see how little torque your VTEK machine puts down?

The only thing I worry about is the amount of tuning one can do with a JWT ECU, since it controls so much of the car. What tools could be used to tune the car with the ECU?

 

I just didn't feel like adjusting the screw anymore that particular day because it was like 10 degrees out and my hands were freezing. It 's not hurting anything so I may just leave it as long as it's opening when it should.

I had a light connected to mine and it made my switch fail after a few months so I don't have the light hooked up anymore. Try setting the switch to open at 6000. I felt the power difference when mine what accidently set to open at that rpm. Everytime it opened when I would hit that range while accelerating.

 

Do you know why it made the switch fail? I believe Paul has had something similar going for a while and hasn't had any problems with it yet. I guess I should just go out and try different settings on the Summit and see if indeed it is opening at 5200, or opening at all.

 

I was probably just running an incorrectly rated LED. I just want to make sure the thing worked.

 

There is another thing totally not related to the car, you may be a slow shifter (no offense just an idea). If you shift alot slower than others with similar mods, you could be wasting .1 or .2 seconds on each shift (1-2 and 2-3) which could easily account for the less than stellar times and trap speeds.

 

Yeah, I've thought about that before. I just worry about shifting too hard, especially with the new stage 2 clutch, because I really can't afford to blow a gear. I'm sure I could shift faster, I'm just not sure how to do it properly. I think I need some lessons from Mardi. With only being able to get in 2 good runs it's difficult to try new things, and get quick shifting/launching down pat. Having the B&M shifter sure doesn't make it any easier...time to get out on a deserted road and do some more practice....

 

$20 it's that damn Summit RPM switch. I had the Harlan switch and then got the Summit switch because I believed the hype about the Summit switch being flawless. It turns out my Summit switch flaked out more than my Harlan switch. I verified the Summit switch to activate at the set rpm with the hood up, but during normal driving and track use, the thing was a POS. My Harlan switch was far more reliable. I swapped back in my Harlan switch and installed a manual activiation switch for when the Harlan flaked out. I verified that the Summit switch flaked out at the track because the week after I removed the Summit switch, my ET/MPHs were .2 and 2mph quicker and faster. No changes to the car, 60', or conditions. My Harlan switch flaked out maybe once or twice a month, if that.

The guy that now owns my MEVI/Harlan RPM switch has had no problems.

Another thing I thought confirmed that the Summit switch was flaky is that I could never really hear the switchover induction change. With the Harlan switch, the noise is VTEC-like and is very audible. With the Summit switch I could barely hear it and sometimes never hear it.

 

Yea, but aren't you sort of the exception to the rule? The Harlan that came with the kit I bought didn't work to begin with, so I bought the Summit. How can I get a sure reading of if it's actually opening during driving? How did you wire up your manual activation switch?
Why do these switches fail at all? You say your Harlan even flaked out a few times a month. Why can't any of these products be reliable? I wouldn't be surprised if the Summit wasn't working at the track since Tilley noticed the car lagging up top when I tried to spray, but he said it felt healthy NA. What gives?

 

I don't think my Summit switch has ever not worked. I too can hear an audible difference at the switchover point. Iron Lung used the Harlan with the MEVI that is now on my car and had nothing but problems. Did you tap into the ECU harness with the Summit switch or at a coil pack?

 

Summit was great for me. In addition to rpm switch activation problems I had with the harlan I also had a vacuum canister problem several times. Are you running an inline check valve with the vacuum canister?

An easy way to tell if the MEVI is activating while driving is to take a piece of scotch tape and lightly put it around the actuator arm. Go for a drive and activate the MEVI by reaching the appropriate rpm point. Pull over and see if the tape is broken or removed by the movement of the arm. I used that method and it worked for me.

 

Tap either to the ECU harness or the TAM screw on the back of you gauge cluster. The Summit Switch when hooked up to the coil pack.

 

Dave is the only person I've ever heard of having problems with the summit switch however, so don't automatically blame the rpm switch.

 

I've had more problems with the Harlan because it was crap. Go figure.....

 

I had tons of problems with the harlan switch, verified when I dynoed it the first time. I switched to the summit, and I have never had it flake out one time. I wired an LED up the switch so I can watch every time it opens, verified by a light on my dash. I think it has alot to do with the way people wire it. Mine may be different. I have power supplied to the MAP/BARO switch all the time, and I let the rpm switch supply ground. I know some people have this backwards from me. I tapped into the ecu wire as well. I tried a wire tap, and it didn't seem to work quite right, so I soldered it and it has never flaked out.

 

I don't know what an inline check valve is, so I'm gonna say no, I'm not using one. I tapped the ECU, not coil pack.
This is just one more reason to get on a dyno...
I wish Paul would jump in here and describe the way he hooked up all the wires. Like I said, I have the Summit hooked up to the Security light, and as far as I can tell the light always lights up about 5200. So if the MEVI isn't opening, at least the Summit is saying it's sending a signal.

 

No problems with the Summit here. Went through 2 Harlans, and they both died/flaked out never worked for me.

Inline check valve is a valve in line of the vacuum to hold vacuum in, but when actuated, release it for "use" like a one way valve, in this case, the use function would open a valve and in turn suck the actuator arm open to activate the MEVI's main operation.

End result, get a dyno.
Until then, follow I30MikeD's advice.

 

did you ever flick the switch to put the ECU back to the NA settings or did you just leave it on the Nitrous setting?

 

If I didn't....I would have been spraying that and my car would have been lit up blue from the switch

 

My Harlan switch is over 3 years old now and it never died. As far as I know, it's working perfectly in my friend's car. My Harlan and Summit switches were wired to the ECU wire. In my friend's car, I wired the Harlan to his coil pack because it was easier. The manual switch did not work with the Summit unit for what ever reason, but was flawless on the Harlan. If and when the Harlan flaked out on the street or on a run, I simply flipped the switch on/off and it reset the Harlan switch. If I wanted to engage the butterflys early or hold the butterflys open once I hit 5200rpms in 2nd, I could. Actually my best ETs/MPHs came when I'd flip the switch on after 5200rpms in 2nd gear and leave the open the rest of the run. The toggle switch was simply wired to ground switch of the Harlan which ultimately grounded the MAP switch. Simply put, the toggle switch manually completed the ground of the MAP switch.

I tell ya what know, I don't miss that thing at all. I was always worried about those little butterfly screws coming loose even though they had loctite. Too bad the 350Z/G intake manifold can't work on the FWD VQs. It has the power curve of the 2K intake manifold, but doesn't have any moving parts what so ever.

 

Any reason it can't work on FWD VQ's other than the fact that the part that bolts to the throttle body is on the side rather than behind the engine?

 

Hood clearance specifically. Emax tried the G35 intake manifold on his 02 Maxima and it wouldn't clear the hood by about 2". Routing the intake tract was another issue.

 

I guess we're stuck with ****ty manifolds... except for SR's secret one, which isn't available.