okay... first time at the track last year i had y pipe back and intake.. this is my slip... street tires on my sawblade rims..

R/T .464
60 2.626
330 6.729
1/8 10.156
MPH 73.34
1000 13.027
1/4 15.462
MPH 92.44


Went down today... Mods... MEVI y pipe back intake street tires with 5 spoke stock rims.. (different then last..)

first run
R/T .577
60 2.636
330 6.910
1/8 10.392
MPH 70.49
1000 13.381
1/4 15.910
MPH 88.64

second run
R/T .025
60 2.655
330 6.989
1/8 10.477
MPH 70.59
1000 13.436
1/4 15.989
MPH 89.12

After that i was heated so i had to leave.. I didnt expect losing about 1/2 a second putting in a 500 plus dollar piece...(mevi) or are the rims playing a factor... im lost and pissed...

 

are you auto, your 60 ft's are awful. people need more info. what does you mevi turn on at? 5000rpm?

 

sorry, I am 5spd and i have my summit switch at 3000 and 200

 

2.6 60' times? bro, work on the launch! dunno bout the variation in times tho, .5 seconds is a lot

 

Your 60' equally sucked both time at the track so I don't think that is the factor. You trapped really low, you should be at about 94-95 mph at least.

Are you sure your VI is working? What rpm is it actually opening at? You might want to go dyno and see how things look.

Not to rub it in, but a 2.6 60' is just really really bad. If you could pull at least a 2.3 60' you would have ran 14's your first time out.

 

Wait, you have your RPM switch set to WHAT? 3000 and 200? I don't understand.

 

Tha is about where I have mine...the summit conversion thing I am guessing.

 

From what it looks like from the slips is your low end isnt as strong. I noticed you gained about the same mph after the 1/8 mile. Maybe your VI is set to open at to low of an rpm and is killing your low end. Man from your first slip you woulda had a 14 at that time if you could have gotten your 60 fts lower.

 

What is the actual RPM it is set to open at, I don't mean the settings on the DIP switches. What is your target RPM.

 

im pretty sure my vi kicks in at 5200. i did just put it in last weekend i will have to check it out.. why is my 60 so bad? because of my launch?

 

im not that experienced with the mevi but doesnt that increase top end and lower bottom? i have seen a couple of people run with the mevi and they all had the same problem. c-max who had a 9lb s/c with auto ran against meccanoble who had 11lb s/c and mevi with stick and lost to c-max. maybe proper tuning of the mevi has something to do with it but just my observation. and also doesnt y-pipe also do the same by increasing top end. im curious because im really interested in the mevi but dont wanna lose downstairs speed because of it.

 

For your MEVI, first try seeing if it opens under no load. Rev to the avtivatioin point while parked. But that does not mean it is always opening under load. A common problem for the MEVI to work while parked in neutral but not while driving is caused by a bad check valve. The vacuum canister will not store vacuum if the check vavle is bad. A way to check to see if you vacuum canister is storing vacuum is to remove hose comming from the vacuum source to the canister. Let the car run for a minute, shut it off and remove the hose. There should be an obvious "rush" from the release of vacuum. A working check valve and vacuum cansiter can hold the vacuum for hours and hours. I can leave my car sit overnight and still get a vacuum release upon removing the hose.

 

i have a nissan vacuum canister.. Does it have a check valve? i know the napa does i am not sure about the factory nissan one tho..

 

ok, I30tmikeD, i just started my car for a min with the hose off. Then i turned my car off and took the other hose off and air came out.. So i would assume it is working properly.. and my vi kicks in at 5200....

 

Well, you were not supposed to have any hoses disconnected while the car was running, sorry if I was not clear. But I am guessing the first hose you had disconnected was the hose from the vacuum canister to the solenoid right? Just have your VI hooked up like normal, run the car for a minute, turn it off and disconnect the hose from your vacuum source to the canister...you should get a release of air.

But I think the way you did it would not affect the outcome, but try it the right way anyhow.

 

okay i let my car run and then turned it off then i took off the hose that is connected to my vacuum source and their was no release of air.. But i then took my hose off that is connected to my solenoid and there was a relase of air.....???

 

Hey i have a ??? I have a 1995 Maxima 5 speed and my take offs at at dead stops sucks. If i take off at 2500-3000 RPM i freaking spin crazy, and if a take off between 1500-2000 rpm i suck. Slow take off and btw hondas are dumping there **** at 5000-6000 rpm. Shape they take me on a dead stop. So whats the best launch offs. I heard from my friend the best is 3000 but feathering it. Anyone heard of this.

 

Maybe I am telling you backwards.....I'll have to go out to my car and see.

Have you checked if the VI is opening just while parked and in neutral?

 

Sorry, I had it backwards. Removing the hose from the canister to the solenoid should give the vacuum release.

So if you can verify VI activation while reving in neutral and the vacuum release when removing the hose then it is most likely working just fine.

 

yeah, it does open in neutral and air is relased when i take the hose off of the canister to the soleniod when the car is turned off. Thanks for your help... so then why are my times so bad? I really feel like i wasted 450 bucks on my mevi....

 

The MEVI is not why you ran slower. There is something going on with the car.

Just to make sure. These were runs were made at the same track? Weather was roughly the same both times out? What was the difference in the rims?

I would consider going to the dyno to see what things look like...

 

Do you think it could be a knock sensor? gas additives? tranny fluid.. lol.. i have no idea i wish i could find out.. Yes these runs were at the same track and the weather was about the same.. My 1st run i had the stock sawblades on then i traded with my dad for his stock 5 spoke.. i highly doubt it could be because of the rims..

 

looks to me like you blazed the tires all the way though first gear and instead of backpedaling you just shifted into second and kept getting it. check your fenderweels and let me know how much rubber you got up in there. I think you just need to learn how to launch the car right. but thats just my opinion.

 

No i didnt spin, i am prtty sure i just need to practice my launch. How do you have a good launch?

 

A lot of people think they don't spin when they do. Sometimes it's a smooth soundless spin. And then sometimes, it's a loud, vicious wheel hop. But if you really didn't spin, then you bogged pretty badly or slipped the clutch a little too much. Try letting that clutch out faster and see if you start to spin. You need to get a more aggressive launch so you are right on the edge of chirping the tires.

But, according to your times, I can bet some money that they are different just b/c of weather. Weather can make someone a full second slower in the 1/4 mile. You don't have to change tracks. Just weather can effect your times more than a full second.

 

its cause you took the sawblade off and put that 5 spokes on... sawblade gives you like 20 extra horse power loll

 

5spoke rims are heavier.

 

Yes they are, but they wouldn't slow him down as much as they did. I can still put money on that it's weather that making him slow.

Zipp028, please find the dates and times of both of those days you are comparing. Also, tell us the city and state that this track is located in. With that info, I can find out exactly what your weather conditions were for those two days and then find out exactly how much slower you would have gotten with that worse weather. Once you compare those two numbers together and level the playing field, then you can start to assume that wheels and other stuff slowed you down. But I am sure that weather was the biggest reason why he got slower.

 

They were at cecil county drag way... the 1st one (my better time) was march 13 2004 at 8:14 temp - 36 humidity - 44 baro 29.04 the other two were on oct 13 2004 6:55 and 7:38 and i dont have a the weather for them

 

go to www.wunderground.com and you can find the weather on any dat for the last few years.