Intakes affecting powerband...what's the deal?
 

You know, when I had my intake installed I noticed that my entire powerband shifted. Flooring at 60-70MPH would downshift into 2nd without the intake (with timing advanced to 17*, this felt like heaven) -- with the intake the car would downshift into 3rd and feel like sh*t. Obviously, this isn't an issue for anyone with a 5spd/6spd -- but it was annoying for me. I'd have to manually downshift to 2nd.

Is it because the intake was installed with the battery connected and the ECU was never reset? What's the deal? Now that the intake was sold (I kinda miss it too...damn money issues) the car shifts and takes off as it did with just the 17* timing.

It was a Berk with Apexi, btw. Not an Injen or some eBay crap.

Basically, allowing more air into the engine decreases torque. That's the reason why we have variable intakes. Nissan engineers designed in both high torque and high hp. Adding an intake (in theory: shut it Irish!) adds hp, but takes away torque.

i don't now Arnold but my tranny seems to downshift the same way with the intake and without and i have an injen with a larger k&N filter. it seems to shift later like its slipping with the intake on like that little extra power which isn't much makes the tranny slip.

Ummm...

I think the VI is to keep intake velosity high at lower RPMs using the longer runners, but when RPMs are higher you are more worried about large quantities of air with less restriction using the short runners.

So I really dont think it is the amount of air decreasing low RPM power, it is the fact that a short ram WAI will decrease velosity because of the lower restriction and shorter overall intake length.

Either way I have a very difficult time believing that an intake was responsible for changing the way the car shifts... I would look elsewhere.

It changes it because the power-band changes. A/T's sense the power output of the drive shaft and changes the gears to match.

Yeah, there isn't anything wrong with my car. Once I took the intake off, the powerband went back to normal and the car dropped shifts approriately.

WTH Arnold. I don't even have it installed yet.

:D

Don't you have a 5spd, though? This shouldn't be an issue for you.

Wish I had a 5spd. Autotragic.

Oh. Do you have your timing advanced? If you don't, then you probably won't notice a difference.

I don't.

Check the eclipse remote thread.