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BMW M30B35 Link G4+ Tune

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hello eveyone,

so this is a costumer tune that been sent to me to check with some datalogs for this engine, this guy car is a fully built M30B35 with vr on crack and cam, running wasted spark 2 coils, 1k injectors and modded fuel system to match the inj, the thing here that the car made about 645WHP on 98oct, but the issue is whenever it hits the fourth gear the car hesitates and a bit of stutters and breaks a piston for the 4th time, i made the guy make some pulls in different boost values as i attached the logs and calibration... i did some mods on the ignition table to be more conservative for the octane level and make sure its not a timing issue...

any advice would help

Attached Files

Some comments after a quick look:

Why do you have 2 ignition and 2 fuel maps switched by DI2 - they are very different? I see you have an aux output labelled "Nitrous", but there doesnt appear to be any other compensation set up to reduce ignition when the nitrous is active. What is the antilag used for and how is the air bypassed? Why is the cam sensor turned off and only injector drives 1 & 2 used? Lambda is not working in any of the logs. The IAT fuel trim table looks pretty odd.

This is how i received it and according to the owner the two tables switched for high octane or e85, nitros is not used no lambda sensor was there since its been tuned on a dyno and the wideband was removed after tuning i know the tune is a mess and already suggested him to retune the car, the thing that i want is just to understand where the problem is in this map, and the cam sensor the M30 engine got only vr on the crank wheel, so any suggestions here would help with this one

It's a little hard to give any solid feedback without more information. Personally I'd say 1.8 bar is a little optimistic for 98 octane pump gas in most instances. You'll most likely find the engine is heavily knock limited and I can't tell you if the timing you're running is too aggressive for the engine. Many elements including compression ratio, turbo size and cam selection will affect the amount of timing the engine will accept.

The fuel map also needs work and I'm not sure what is going on with the step in fuel table values around 276 kpa and 5000 rpm. Your master pulse width should be reduced to get some resolution into the map (max values should ideally be 70-80, not 60 ish, and since you're running 280 kpa I'd also extend the fuel and ignition maps so they are spanning beyond the range of MAP values you're actually running.

Basically I'd suggest a full remap so you know everything is tuned correctly.

Thanx Andre

i will remap the whole thing but my question here can i run a moddled fuel equation and sequential with only vr on the crank since this car got only crank sensor from the factory

You cant run sequential without a cam sensor. I only mentioned sequential earlier as your first post stated "VR on crank and cam". If there is no cam sensor then you will have to stick with the multipoint group/wasted spark set up.

There is nothing stopping you from using modelled fuel equation however.

Adam, my mistake

thank you guys for the help

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