Dyno issues

321eurotuner · 06-19-2023, 11:47 PM

What’s everyone’s work around to getting your RWD car to cooperate on the dyno?

Today I had my 2018 340i rwd on a Dyno Jet. We did a baseline run 2 months ago before I installed my upgraded turbo and it did fine in Roller Mode. No issues.

Today, I put the car in roller mode except it would cut at 4200 rpm every time. We tried having the hood open, closed, Sport +, DSC Off, roller mode. I even took it off the dyno to drive it around to clear out the ABS/brake fault and it was fine. No codes or errors. Back on the dyno and the same thing.

Any ideas?

blacksapphire440i · 06-20-2023, 01:48 AM

Quote:

Originally Posted by 321eurotuner

What’s everyone’s work around to getting your RWD car to cooperate on the dyno?

Today I had my 2018 340i rwd on a Dyno Jet. We did a baseline run 2 months ago before I installed my upgraded turbo and it did fine in Roller Mode. No issues.

Today, I put the car in roller mode except it would cut at 4200 rpm every time. We tried having the hood open, closed, Sport +, DSC Off, roller mode. I even took it off the dyno to drive it around to clear out the ABS/brake fault and it was fine. No codes or errors. Back on the dyno and the same thing.

Any ideas?

I recently got my car dynoed and had "successful" dyno runs as in I was able to fully get through the RPM in 5th gear. The problem I was facing was the 2048 torque limiter which basically held back power throughout the powerband and while my tuner tried to fully disable that soft limiter the car ended up cutting around similar rpms 3500-4500rpms.

For the future you should ask the dyno operator to set the dyno in AWD mode if its a dyno jet. At that point I think the hubs need to be locked? Or you need a tow hook. That should completely eliminate any problems and should run at your tune's power level

321eurotuner · 06-20-2023, 08:42 AM

I was reviewing my baseline GoPro videos which were filmed from inside the car and saw that the speedometer was showing 0mph. If I remember correctly, yesterday it was showing a speed. I’m thinking that the car wouldn’t go into dyno mode? It still doesn’t make any sense to me based off everything that we tried. Under partial throttle the car had no issues going to 6000 rpm. Once it was under load it would cut at 4200. On the street, no issues.

06-19-2023, 11:47 PM	#1
321eurotuner Private 3 Rep 86 Posts Drives: F30 340i Join Date: Mar 2010 Location: Rip Rancho, NM iTrader: (0)	Dyno issues What’s everyone’s work around to getting your RWD car to cooperate on the dyno? Today I had my 2018 340i rwd on a Dyno Jet. We did a baseline run 2 months ago before I installed my upgraded turbo and it did fine in Roller Mode. No issues. Today, I put the car in roller mode except it would cut at 4200 rpm every time. We tried having the hood open, closed, Sport +, DSC Off, roller mode. I even took it off the dyno to drive it around to clear out the ABS/brake fault and it was fine. No codes or errors. Back on the dyno and the same thing. Any ideas?
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06-20-2023, 08:42 AM	#3
321eurotuner Private 3 Rep 86 Posts Drives: F30 340i Join Date: Mar 2010 Location: Rip Rancho, NM iTrader: (0)	I was reviewing my baseline GoPro videos which were filmed from inside the car and saw that the speedometer was showing 0mph. If I remember correctly, yesterday it was showing a speed. I’m thinking that the car wouldn’t go into dyno mode? It still doesn’t make any sense to me based off everything that we tried. Under partial throttle the car had no issues going to 6000 rpm. Once it was under load it would cut at 4200. On the street, no issues.
	Appreciate 0 Quote