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Old 06-04-2017, 05:59 PM
550iFreak 550iFreak is offline
Registered User
Location: Deltona FL
Join Date: May 2017
Posts: 27
Mein Auto: 2011 F10 550i 6MT
Thanks bud

Well, the ONLY negative side effect ( and if you even consider this a negative effect but you should be expected if you own such a beast) is a very slight decrease of MPG. And I mean 0.1 of a mpg lost on your average. Since it is running cooler, the car will tend to run a tad richer than usual. But the positive effects outweigh this such as:

Longer overall engine life

Less stress on critical/sensitive components such as coolant lines/plastic connections, turbos,etc

More consistent and powerful performance at operating temps( timing and other parameters able to give full potential)

Excellent in areas that ambient temps are usually on the high side(Floriduhhh) so no more heatsoak or reduced power output due to higher temps.

Coolant/oil consumption reduced( I noticed before I had to add coolant. Even though it was a small amount, I do need to top it off here and there. Now to this date, it is still at MAX level. My oil consumption also improved as well. I still dont need to fill oil yet and I put almost 2k miles on it already).

Also, still to this date, It did NOT trigger a check engine light nor a malfunction light. I was spirited driving with a Fiat Abarth lol....and we were having fun until boof my malfunction light came up and my oil temp reading at 250. I was running hard though. After putting the 90C, I NEVER got one and I do drive it hard time to time. Even now with your former precious JB4 file, it still doesn't trigger it. Just hauls ASS hahaha.

I did notice one thing though that is funny, and must be related to the JB4 stg 2 tune. Before, I consistently pull 95-97C at any engine load applied to it. Now when I go WOT, it drops considerably to as low as 79C O.o . Give it a minute and it will gradually go back up to 96C. When I am cruising and not go stupid, it will stay at stock 96C until I hit the gas, Then it will go back down depending how long I WOT. I am sure that the JB4 is doing this and thought it was an issue but then again those running the JB4 for many miles and still have no issues meaning it must be fine. Then again...they were running stock 105C thermos. Hmmm...something to look into once I get my cable.