[dr.mba]

Hello everyone,
Been thinking about this for a while. As some of you might know, I had the N55 JB4 stage 1 installed and then went ahead and bought the race chip. I have been happy with the performance of the race chip overall but miss the explosiveness that came with the JB4. I have been thinking for the last week about running both tunes in tandem, with the base tune being the race chip and the override with BMS stage 1. I was a bit scared that this maybe a bad idea, as it may not be the safest thing to do. I gathered my courage and did this today. I have not pushed the car at all, I just wanted to see if there would be any CEL thrown, and guess what.... It runs just fine!
Now before I go punching the pedal to the metal, I would appreciate if anyone here, who is more technical than me, could give some sound advise whether I should be doing this to start with! For your information the car is owned, so I don't want to ruin it/damage the drivetrain... Please chime in..

MBA

[Alan l.]

Running two tunes without any logging just sounds like a real BAD idea.

You don't want the tunes to stack boost over each other because the car won't be able to adjust the fuel/timing enough to compensate for it.

I've seen people stack a piggyback tune over a flash tune before but not two piggy back tunes.

Alan

[dr.mba]

What do you suggest Alan? I do have the OBD connector that came with the BMS....

MBA

[gtron]

i voted yes but only because it's awesome and i want to see what happens.

[ManiacGT]

I'd have thought you're either going to get one over riding the other, or two combining/interfering and causing unknown issues. I'd leave well alone and stick with one or the other. Its all very well having a quick car for 5 minutes and then a 20K bill to repair an engine and/or gearbox.

[dr.mba]

Went for a spin, didnt push the limits or anything. Car is gone insane! The DTC wouldnt stop flashing up to 3rd gear!! I am astounished at how this is working. The guys at BMS must not be pushing limits at all if this is what I am getting out of the tunes. Thankfully no CELs thrown so far or limp mode activated. Curious to know how much power I am generating now!!

MBA

[Klecha man]

Originally Posted by dr.mba

Went for a spin, didnt push the limits or anything. Car is gone insane! The DTC wouldnt stop flashing up to 3rd gear!! I am astounished at how this is working. The guys at BMS must not be pushing limits at all if this is what I am getting out of the tunes. Thankfully no CELs thrown so far or limp mode activated. Curious to know how much power I am generating now!!

MBA

why don't you just max out the tune setting on the RaceChip to see what it can do. Maybe one of the settings could behave like both combined?

[RambleJ]

How did you get both tunes on at once? Do they not use the same plugs?

[berkel]

You could try running higher octane, but you would need to know where you are in terms of boost, timing, EGT, and A/F ratio to determine whether it's "safe" or not.

With more boost, and/or timing, it may increase the octane requirement above 93, so adding more may add a little protection... Ideally you would dyno/log the parameters and see if you are "safe", or try adding higher octane to see if it can get you into the "safe" range where EGTs aren't too high, A/F is ok, etc.

Good luck!

[dr.mba]

Originally Posted by RambleJ

How did you get both tunes on at once? Do they not use the same plugs?

They both have two connectors. One is supposed to connect to the car to get input and the other connects to the sensor to modulate effect. I thought if Iplugged one of them to the car and then to the other then to the sensor it could work and so one would alter the effects of the other. I thought for sure a CEL would be thrown but was wrong. The car works so far just fine. I am a little nervous so I am not pushing any limits. I should get a dyno done like someone suggested..

MBA

[dr.mba]

Originally Posted by Klecha man

why don't you just max out the tune setting on the RaceChip to see what it can do. Maybe one of the settings could behave like both combined?

I had the race chip maxed and then backed the settings because of increasing lag. I had the idea for a while because I know the race chip has better throttle response where as BMS has better higher rev delivery so combining them made sense to me especially that only 2 sensors would need to be hacked. This is more of an experiment to me. I honestly thought the car wouldnt run right. I am not sure what I will do with it later. I am running 94 octane.

MBA

[gtron]

awesome

[Klecha man]

Originally Posted by dr.mba

I had the race chip maxed and then backed the settings because of increasing lag. I had the idea for a while because I know the race chip has better throttle response where as BMS has better higher rev delivery so combining them made sense to me especially that only 2 sensors would need to be hacked. This is more of an experiment to me. I honestly thought the car wouldnt run right. I am not sure what I will do with it later. I am running 94 octane.

MBA

wow, you're gutsy to try this... I think you should just upgrade to a 550 or M5, then you would not have to worry about all these tunes... LOL

I'm hoping to install the tune tonight, they initially sent me the wrong connectors and just got the correct one yesterday. Looking forward to it.

[scott135i]

BAD IDEA - Unless on of the two tunes has been specifically designed/modified to work in tandem.

[HighConcept]

Originally Posted by Alan l.

Running two tunes without any logging just sounds like a real BAD idea.

You don't want the tunes to stack boost over each other because the car won't be able to adjust the fuel/timing enough to compensate for it.

I've seen people stack a piggyback tune over a flash tune before but not two piggy back tunes.

Alan

+1