Car loss hp/tq?
Thread Starter
Junior Member
Joined: Jul 2017
Posts: 56
Likes: 5
C43
Car loss hp/tq?
First of all my car is with cat-less down pipes and stage2 tune.
Recently I felt my car does not pull as hard as before especially at mid-end speed and above.
I switched to engine data meter and made a pull, I noticed the horsepower cap at 486hp and torque cap at 489 lb-ft. Is it normal?
Then, i did a 1/4 mile run with dragy and ended up 12.6 sec, and 60-130 pull ended up 12.7 sec, which is very very slow I know.
The issue seemed to happen after I had the dps installed.
I came across the thread that some members having similar issue which was caused by low battery voltage back in 2017.
Before I take any action, I want to see if anyone is experiencing this recently or any comments.
Even much appreciated if anyone in Orange County, California can have a side by side run with me as a bench mark.
Recently I felt my car does not pull as hard as before especially at mid-end speed and above.
I switched to engine data meter and made a pull, I noticed the horsepower cap at 486hp and torque cap at 489 lb-ft. Is it normal?
Then, i did a 1/4 mile run with dragy and ended up 12.6 sec, and 60-130 pull ended up 12.7 sec, which is very very slow I know.
The issue seemed to happen after I had the dps installed.
I came across the thread that some members having similar issue which was caused by low battery voltage back in 2017.
Before I take any action, I want to see if anyone is experiencing this recently or any comments.
Even much appreciated if anyone in Orange County, California can have a side by side run with me as a bench mark.
MBWorld Fanatic!
Joined: Jun 2014
Posts: 1,589
Likes: 683
From: IL
19 E63s, 23 M3 compX, B9 SQ5
Who is your tuner? Scan for codes as mentioned above. Might also want to see if your car is slipping the clutch in WOT 2-3, or 3-4 upshifts. Catless Downpipes themselves should not cause any issues, this is probably tune related. Depending on your mileage might want to check the spark plugs also, but you'd have codes for misfires.
MBWorld Fanatic!
Joined: Aug 2012
Posts: 1,218
Likes: 315
From: Pearland, Tx
2020 AMG GTC Coupe & 2018 Macan Turbo
Years ago, John Hennessy came to the BMW shop one day and was complaining to my service manager that the new exhaust he had designed and installed on the infamous e39 M5 made the car run slower. Your problem is possibly a case of a louder exhaust but overall makes the car run slower. Might be suffering from a trade-off. Noise vs. power. Might not be the battery. It also might be that all of the products are not 'married' to each other. All your mods might need to be looked at wholistically by a professional tuner.
GL and let us know what you find. It helps the next guy.
GL and let us know what you find. It helps the next guy.
Super Member
Joined: May 2011
Posts: 883
Likes: 72
From: Vancouver
2018 e63s edition 1
A properly tuned car with downpipes will simply make more power on a turbo car, always. Like said above, could be an issue with the tune in general, maybe the car is running way too lean and pulling timing like crazy to try and hit the AFR target set in the tune. Also like already mentioned, plug the car into a reader and see what codes there are and if there isn't any, get it data logged and/or put on a dyno and get some numbers/ AFR readings to see what it's doing. The downpipes themselves won't be the issue. A properly tuned car with downpipes should make considerably more HP/TQ. The interesting thing is the cars onboard HP reader doesn't actual read HP, it just guesses based on throttle position, boost,etc, so something is obviously going on with it. It's like when the PE cars unplug their exhaust valves and the car stops itself from making boost/power so the HP gauge in the car will only ever read around 300 max.
