W211 M156 Boosted

Hello everyone. I've done diy rear turbo install in the trunk and intake piping go under the car and to up under the hood. Most pipes are 2.5 inch and a bit less at some bends. Fabricated all myself, was fun project and I'm not a professional in fabricating, welding or tuning by any means. First start after install was finished car did start but died few seconds later, tried giving a gas it helped to keep it running for couple more seconds. Got into tuner, rescaled my MAF calibrations tables(MAF 1 44328 and MAF 2 44329) lowered Airflow in a whole row by 0.8% approximately from 3,773 lb/h to 2,950 lb/h at 0 Period(μs) and car started and ran fine but quiet a bit lean. Then I've changed Inj Pulse Mult corrections table(1237) by increasing values so injectors would stay opened for longer and my AFRs full throttle now 11-12 and 14-15 cruising. Won't go too much into details but if you guys know what should I do please let me know. Also I did blocked crank case ventilation port in intake manifold so I won't pressurize engine block.

My setup:
eBay turbo GT45 T4 V-Band 1.05 A/R 98mm
Compressor
Trim: 50
Inducer Diameter: 69mm
Exducer Diameter: 98 mm
A/R:0.66

Turbine
Trim:78
Inducer Diameter: 88mm
Exducer Diameter: 77.5 mm
A/R:1.05

Blow off valve: UNIVERSAL BILLET ALUMINUM TYPE-RS TURBO BLOW OFF VALVE BOV+2.5" FLANGE TUBE PIPE

Wastegate: 60mm Bolt-on 5/12/14 PSI (currently 12 psi, i had 5 but I believe it was opening too soon and dump pipe was black)

Now the symptoms. When hitting 0 psi on boost gauge and trying to go into boost, car loses power and turbo fluttering is happening but I haven't let off the gas. If I get hard acceleration car goes to limp mode. ESP light on, stop, restart the car and it's back to good. Maxed out MAF and map values in engine diagnostic and still getting MAF error p0101 for both MAFs. I've heard I might need to make a bigger MAF housing for it to read less weight and be more stable

https://youtu.be/kuQS1FkilhQ
https://ibb.co/gRQ4pZQ
https://ibb.co/TKfCTb3

please attach photo of tube where is maf is located. than if you have changed injectors = you have no way to dial in it properly with HP tuner
you need to tune your car using other tools

Why can?t aftermarket injectors be dialed in with HP Tuner? Many has dialed in larger injectors for supercharged M156 or even just for flex fuel.

Quote:

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Originally Posted by RomanVR

Hello everyone. I've done diy rear turbo install in the trunk and intake piping go under the car and to up under the hood. Most pipes are 2.5 inch and a bit less at some bends. Fabricated all myself, was fun project and I'm not a professional in fabricating, welding or tuning by any means. First start after install was finished car did start but died few seconds later, tried giving a gas it helped to keep it running for couple more seconds. Got into tuner, rescaled my MAF calibrations tables(MAF 1 44328 and MAF 2 44329) lowered Airflow in a whole row by 0.8% approximately from 3,773 lb/h to 2,950 lb/h at 0 Period(μs) and car started and ran fine but quiet a bit lean. Then I've changed Inj Pulse Mult corrections table(1237) by increasing values so injectors would stay opened for longer and my AFRs full throttle now 11-12 and 14-15 cruising. Won't go too much into details but if you guys know what should I do please let me know. Also I did blocked crank case ventilation port in intake manifold so I won't pressurize engine block.

My setup:
eBay turbo GT45 T4 V-Band 1.05 A/R 98mm
Compressor
Trim: 50
Inducer Diameter: 69mm
Exducer Diameter: 98 mm
A/R:0.66

Turbine
Trim:78
Inducer Diameter: 88mm
Exducer Diameter: 77.5 mm
A/R:1.05

Blow off valve: UNIVERSAL BILLET ALUMINUM TYPE-RS TURBO BLOW OFF VALVE BOV+2.5" FLANGE TUBE PIPE

Wastegate: 60mm Bolt-on 5/12/14 PSI (currently 12 psi, i had 5 but I believe it was opening too soon and dump pipe was black)

Now the symptoms. When hitting 0 psi on boost gauge and trying to go into boost, car loses power and turbo fluttering is happening but I haven't let off the gas. If I get hard acceleration car goes to limp mode. ESP light on, stop, restart the car and it's back to good. Maxed out MAF and map values in engine diagnostic and still getting MAF error p0101 for both MAFs. I've heard I might need to make a bigger MAF housing for it to read less weight and be more stable

https://youtu.be/kuQS1FkilhQ
https://ibb.co/gRQ4pZQ
https://ibb.co/TKfCTb3

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if DIY i give you respect, but please get some training on welding / fabrication.

I know i did bad man, but i got better since, check out my new thread:)