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      09-23-2020, 06:28 PM   #54
Tim2189
Russian in a Bimmer
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Drives: X5 M50i
Join Date: Jul 2008
Location: Brooklyn NY

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Quote:
Originally Posted by 130FeetDeep View Post
Quote:
Originally Posted by speedyman View Post
^^^^^^This, exactly. Sucks as I would much rather have a true ECM flash. I'll probably give one of these piggy backs a try but just have concerns about the lean conditions that I've seen in these logs.
I read through a few threads about JB4s on another forum and some of the guys claim to have some serious SOTP improvements in M5s and M550is.
How much boost do you think these motors can handle and stay in one piece for say 50,000 miles? My prior experience is with supercharged Ford V8s with Zoeler forged pistons, forged crankshafts, Manley 4340 rods. Going from 8 lbs to say 14 on those 4.6L motors was a profound increase in performance as in going from 13 second 1/4 miles to mid 11s.
I'm nowhere near the break in point on my '21 M50i and have not run it anywhere near redline but am seriously impressed with the stock power and that is here in the SW FL severe heat and very high humidity none of which are favorable to FI engines.
The motor has proven strong over the years despite some of its oil burning issues over the years. I haven't seen that on the R, but we shall see. The fuel system seems to be having zero issues based on the logs Tim posted. AFR stays north of 14.5 right to redline, so we have plenty of headroom.

My only concern is the timing drops showing up in Tim's logs. I also am not sure why he is seeing 22 lbs of boost when the map he is running should only target 18?
From my understanding and looking at Map 0 logs, stock boost is 16PSI Max, map 2 adds up to 6psi so 22psi would be the limit on the jb4 for now. I ran map 3 and got 18psi max, map 5 got 20psi max and the car didn't feel as refined during those pulls. I didn't wanna do the pulls again so I wasn't able to log them.

This is day 3 of running map 2 and it pulls like a train on the highway, that is where I see majority of the improvement. Overall I'm happy with the set up and think it's worth the money and only 45 min install.
Another positive is that it's a piggy back so you won't get flagged when you go into service which Is major.
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2013 X6 - retired
2015 X6 - retired
2015 435GC - retired
2018 X5 40e - retired
2020 X5 M50i - Current
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