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Rotzy · 03-18-2017, 10:05 PM

I ordered and received a RC Ultimate for my 2016 50i from RGSport. As usual, great service and fast shipping.

I got it installed tonight, set S2 to "C" and took it for a 10 mile drive. Overall first impression is not great. I feel like it lost some low end torque and turbo lag seems to have increased. This is particularly noticeable when trying to accelerate in a low rpm, high gear scenario: ie, on the highway and attempting to accelerate without downshifting.

Towards the end of the drive, I did do a couple WOT runs and I was a bit befuddled with the results. First gear seemed sluggish through the entire rev band, second gear hits like a ton of bricks and pulls way harder than first. Weird.

I am seeing an increased maximum boost pressure of about 1psi, so I know the tune is doing something. When doing some pre-tune runs earlier this week, I saw a maximum boost of 14psi. Tonight I saw 15psi twice.

I know I need to give the engine some time to learn the tune, but does this seem normal? Does it get better over time?

* EDIT 3/20/2017 *

I take back some of my above comments. Turbo lag is in only my head. There is such an increase in top end power that I was perceiving the difference as lag. The "poor" acceleration in low rpm/high gears I mentioned above is no worse than before the RC was installed.

I'm still waiting to see if the WOT in first gear improves.

I did receive a drivetrain malfunction today, so I'll be watching that closely and possibly removing the RC permanently if it continues. I can't risk my wife getting stuck.

* EDIT 4/10/2017 *

I'm still impressed with this tune. Head over to post #161 for dyno numbers or click the link below.

http://f15.bimmerpost.com/forums/sho...&postcount=161

03-18-2017, 10:05 PM	#145
Rotzy Captain 508 Rep 648 Posts Drives: 2016 F15, 2015 F83 Join Date: May 2014 Location: RI iTrader: (0) Garage List 2015 M4 Convertible [0.00] 2016 X5 xDrive50i [0.00] 2006 Z4 3.0i [0.00]	I ordered and received a RC Ultimate for my 2016 50i from RGSport. As usual, great service and fast shipping. I got it installed tonight, set S2 to "C" and took it for a 10 mile drive. Overall first impression is not great. I feel like it lost some low end torque and turbo lag seems to have increased. This is particularly noticeable when trying to accelerate in a low rpm, high gear scenario: ie, on the highway and attempting to accelerate without downshifting. Towards the end of the drive, I did do a couple WOT runs and I was a bit befuddled with the results. First gear seemed sluggish through the entire rev band, second gear hits like a ton of bricks and pulls way harder than first. Weird. I am seeing an increased maximum boost pressure of about 1psi, so I know the tune is doing something. When doing some pre-tune runs earlier this week, I saw a maximum boost of 14psi. Tonight I saw 15psi twice. I know I need to give the engine some time to learn the tune, but does this seem normal? Does it get better over time? * EDIT 3/20/2017 * I take back some of my above comments. Turbo lag is in only my head. There is such an increase in top end power that I was perceiving the difference as lag. The "poor" acceleration in low rpm/high gears I mentioned above is no worse than before the RC was installed. I'm still waiting to see if the WOT in first gear improves. I did receive a drivetrain malfunction today, so I'll be watching that closely and possibly removing the RC permanently if it continues. I can't risk my wife getting stuck. * EDIT 4/10/2017 * I'm still impressed with this tune. Head over to post #161 for dyno numbers or click the link below. http://f15.bimmerpost.com/forums/sho...&postcount=161 __________________ 2016 F15 X5 50i M-Sport 2015 F83 M4 Last edited by Rotzy; 04-10-2017 at 07:52 PM.. Reason: Added more comments.
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