From testing today...
CF: 1.05
2011 135, 7DCT
Mods: Procede v5 3-21, Vishnu DP, Vishnu Charge pipe, muffler shop cat-back with dual 2.5" magnaflow mufflers, tightened wastegate actuator
91oct
CF: 1.05
Tested in 5th gear (6mt and 7at should dyno in 4th gear)
Graphs represent the following settings:
15psi, 50%IC
14psi, 50%IC
12psi, 50%IC
Stock Tune
Observations:
-Due to turbo capacity limitations, all tuned settings make about the same power/boost above 5500rpm. So different boost settings just effect midrange and low end power/boost. The turbo is so flow limited that it will not support more than 14psi at 5000rpm. And by 6000rpm, it's down to just under 12psi. Perhaps upgrading the FMIC will reduce some pressure loss and increase top end boost/power. We will be installing an upgraded FMIC next week and will re-test.
-We found that slightly tightening the wastegate actuator helped the turbo maintain slightly more top end boost. Not a lot. Just a little (0.5-1psi) This mod is easy to do when installing a downpipe. All you need is a 10mm wrench. Shortening the wastegate rod no more than 1/4 of an inch. If you shorten it too much, you will experience overboost in the 3700-4000rpm.
-The DME refuses to let the car run beyond 6500rpm when dyno testing in 5th gear. This is because it throws a 13001 code for "Poor Road Surface" due to the fact that the front wheels aren't spinning along with the rears. Funny.
-Here's a datalog of the 15psi run:
I'll post a "how to dyno your n55" once i finish writing it. There are a few unique issues with this platform. They are worth mentioning.
Cheers
shiv