N55 Pure Stage 1, $1k to get where the N54 guys are

[Solo_M_Tech]

A gradual reduction in torque is normal. I think my definition of "falling on its face" is different than most.

[houtan]

Originally Posted by HooningB2G

A gradual reduction in torque is normal. I think my definition of "falling on its face" is different than most.

I think falling on its face means at 5k you are making 17psi, at redline you are probably closer to 9 or 10 psi. and it happens quickly. to me that is falling flat on its face.

that's why shifting around 5500 rpm is much faster in a straight line than if you were shifting at redline on the stock n55 turbo.

[Vigilante375]

Originally Posted by HooningB2G

I don't understand why people say the N55 falls on it's face at "4k" rpms etc. Mine pulled hard all the way to 6200 rpms or so. Stock. Now with the JB4, kittyless DP, intake, and CP, My N55 has no dicernable lag, and pulls hard to redline. Boost taper starts at 5k rpms. From 17 psi to 14.5.

Look at stock or even modded 135i dyno's. You'll see the power decrease around ~5500 RPMs and at redline, its dropped a lot. Thats the "falling on its face" reference. The car might feel like its pulling but your sense's failing you. Go ride in something else that makes power ALL THE WAY to the redline and you'll notice the difference.

From peak HP to redline, the drop is about 15-20 rwhp and sometimes more. That might not sound like a lot but it could mean the difference in winning a race.

[loesch]

Here is an example of "falling on face".

[Nugget]

Another example of falling on it's face.
Red line = stock
Green line = fbo stock turbo
Blue line = Vargas stage 2 turbo with mild pump gas map.
Look at the green line plummet after 5000rpm.