Cisco

For some reason, my car seems slower after I installed the intake. Does anyone have any ideas what's going on?

GC

UMD_MaxSE

iTrader: (1)

people have noticed that off-the line performance decreasing wth the cone type intakes. High end should be better, but low-end may suffer a bit.

Cisco

When you say "high end" at what speeds are we talking?

GC

Sonic

You lie, intake air velocity has nothing to do with this. OH, and high end = >5000 RPM.

Keh mon

Hey thanks for sharing JERK
How much of a negitive effect does the non-CAI intake have if it's mated with a Y-pipe. Or does that emphaize it more because it's "less restrictive too."

IceY2K1

iTrader: (3)

That's what happens when you MESS with a "tuned" factory intake tract. Nissan optimized it for maximum horsepower/torque across the whole powerband. The cone intake supposedly adds peak horsepower on the TOP end, but you usually trade-off some LOW end torque.

For the torque you need a plenum of air like the stock air box provides, but once your intake runners switch over at 5000rpms(??) your airflow is restricted by the air box. Therefore, you need to decide what is more important. Looks, top-end, and most of all sound of the SI or the extra torque of the stock air box.

PhatGuy

Is your car 5spd or auto?

woosh

Will you eventually share your CAI with the group?

IceY2K1

iTrader: (3)

So TRUE.

Nissan also has another constraint and that's COST. Nissans' "optimal" tuned intake is not necessarily the BEST because of performance, but a combination of several factors such as performance, noise, manufacturing cost, etc... Which means there is ALWAYS room for improvement and one day I hope to have a business that takes advantage of this market.

emax02

iTrader: (1)

I will be waiting for this .

IceY2K1

iTrader: (3)

If it doesn't require cutting and you need an "independent review" let me know. I have a G-tech Pro, OBD-II software, and reasonably cheap access to a dyno to put it to the test.

Jon91SE

Run a 1/4 and compare times with stock airbox and SI , i doubt your running slower now with the SI , it may seem slower because of the way the noise builds up as the revs build up. On a hot day it will slow you down a bit off the line, but an intake is increasing air flow and is less restrictive then stock, period. I think some of this low end loss people talk about is exaggerated and not backed by 1/4 times, remember an exhaust dosent help low end performance either, but you dont start going faster until you add these bolt on's................

Cisco

Do u guys notice a whining/churning noise at WOT? I also hear a whistle at idle. Is this normal?

GC

IceY2K1

iTrader: (3)

Yes, the whistle sound is normal for a Stillen or JWT cone intake.

ohboiya

iTrader: (3)

H ... why r u being like that?

J/K ... I'll drop u an e-mail .. c wazzup!

nc00max

I have the JWT and have barely noticed any drop at all in low-end, and a definite bump in high-end. I left the front part of the stock air intake on so it would still get outside air at a halfway decent pace. It may not be doing jack for me, but like I said, I barely noticed any difference, except for some sweet gains up high. And yes, that's a different bolt on the front of the air scoop. Where the old one is, I don't know.

UMD_MaxSE

iTrader: (1)

well, you have y-pipe and UDP also, so that may make up for any low-end discrepancies

nc00max

This is true, but the JWT was actually my last mod. Before that was the OSCAI, and everyone said I would lose low-end, but maybe the UDP is doing all the extra work on the low-end. Oh well, as long as it's there, right?

IceY2K1

iTrader: (3)

The slush box will make it less noticeable than on a 5-speed.

cobymoby

iTrader: (2)

Cisco, are your wheels 17 or 18 SSR's?

Cisco

17 x 8

AznWontonboy

i knew it. i knew you wuold finally build that dirt devil intake i prototyped. send me the blue prints crediting me for some of the work.

UMD_MaxSE

iTrader: (1)

wonton powered intake

costcowholesale

iTrader: (12)

this sounds kinda stupid but someone said the airbox is restricting the airflow in highend. What if you drill some holes on the airbox wouldn't that solve the problem?

Sonic

That would make you slower.

IceY2K1

iTrader: (3)

That's an old Sentra trick I learned. Russ knows what I'm talking about. You remove the bottom half of the 2-piece air box and tie the filter to the top half that connects to the intake tract. It's a MEAN growl, but DAMN the filter gets dirty quick.

Since our air box is 1-piece the only worth while air box mod would be to cut off the front side of the air box in FRONT of the filter. The only draw back is that you'll be injesting ALL hot underhood air at low speed, but when your concerned about top end it doesn't matter.

I was considering do something like this so that I could remove the drivers' side headlight and make some kind of ram air tract to the air box for the 1/4.

NZ Max

NZ Max

I did this to my Cefiro. The only thing I did different was that I got an angle grinder and chopped the bracket peice off the bottom peice of the cold air box to hold the filter in place. The growl was cool, it also made quite a nice rumble at half throttle over about 3000 rpm. I tried it in 2 positions, 1 facing the bottom of the car and the 2nd with the MAFS rotated 1/4 turn so the filter faced the back of the battery. It was louder in the 2nd position but just a bit slower. It killed low end a bit and gave little mid to high end. I just (2 days ago) set it back to stock (I had to use glue and bog to fix the cold air box) and my low end is back but I admit the mid to high sucks compared to what it was with the modified version. I got sick of the noise and I might be selling soon as well.
My cefiro came from japan and has the same variable intake manifold as roadbeast which gives major boost (in power I mean) at 5k rpm.

Overall, I think Id do this again since Im el-cheapo with my d's but Id hack up my cold air box and get another one to replace it with when I got sick of it again.

2K2DEMAX

iTrader: (1)

Actually, I did. With the JWT intake I was only able to muster a 15 flat consistently. With the OSCAI I got down to 14.8 consistently. Now what I have is the CAI + JWT, meaning the JWT stack clamped onto the CAI tube(I had to get an intake adapter to get on the JWT). Let me tell you, the difference is VERY significant, all throughout the RPM band. BTW, before I put on the JWT onto the CAI tube, I ran with the cylindrical K&N that comes with the PRCAI for about 10 days. Car felt great, MUCH better than the OSCAI or JWT alone. Now when I clamped on the JWT to the PRCAI, it was even better, I would say getting the best of all worlds, so to speak. This WILL be verified at the track soon though, probably in about three weeks. Based on what I've seen, I would definitely recommend anyone changing from JWT/Stillen intake to the PRCAI to try this.