[Mo T.]

Recently bought a non-comp, pre-LCI F90 M5 and did some draggy runs. It’s been pretty hot and humid lately but I don’t know if the car should be this slow. 60-130 time was during the day with tailwind @13mph with one passenger and full tank of gas. 0-60 was with a 2.5k rpm brake boost launch later that night but with no passenger and still nearly full tank. Temps are on the draggy as well as elevation and DA. Humidity was 60% for both runs. Car used to be driven in California so it’s mainly used 91 it’s whole life but I filled it up with 93 before these runs. Another thing I noticed is the lack of soot on the tailpipes. Most BMWs I’ve seen always have a little amount of soot but the tailpipes are clean on this one, unless someone can send photos for comparison?

Thoughts?

[pbonsalb]

The ECUs may have adapted to the 91 octane, the humidity hurt, and brake boosting is not as effective as launch control. The times look slow to me even for a 5 year old stock car. I don’t think comp vs noncomp makes a difference, but the level of factory equipment makes a slight weight difference — sunroof and 706M wheels probably cost 100 lbs and a full tank of gas could add 100 lbs compared to what most carry when recording numbers. That is like carrying a passenger. Not sure whether you are light or heavy but weight affects acceleration.

I would service the car, install engine and trans tunes, and add water/meth injection. If charcoal filters are still in place, remove them. If you can do catless secondaries and pass inspection in your area, consider them.

[Mo T.]

Originally Posted by pbonsalb

The ECUs may have adapted to the 91 octane, the humidity hurt, and brake boosting is not as effective as launch control. The times look slow to me even for a 5 year old stock car. I don’t think comp vs noncomp makes a difference, but the level of factory equipment makes a slight weight difference — sunroof and 706M wheels probably cost 100 lbs and a full tank of gas could add 100 lbs compared to what most carry when recording numbers. That is like carrying a passenger. Not sure whether you are light or heavy but weight affects acceleration.

I would service the car, install engine and trans tunes, and add water/meth injection. If charcoal filters are still in place, remove them. If you can do catless secondaries and pass inspection in your area, consider them.

I have the carbon fiber roof and 20in. seven double spoke wheels. The car is currently at 40k miles and had an oil change done. Plugs were changed at 20k miles with air filters. Owner confirmed the plugs have not been changed since and has no idea if the air filters have been changed. Will plugs, filters, and resetting adaptions drop a second or more for 60-130? When are coils changed on these cars? The car also has the original lpfp.

Thanks

[Ropes]

I wonder if your coolant for the intercooler is low. This will cause your call to pull timing due to the hot air from the turbos. It may not have hit a point to throw a code.

[pbonsalb]

Resetting adaptions, driving for a bit with 93 or 91 plus some E85, cooler and drier weather, and launch control should help.

[Mo T.]

Originally Posted by Ropes

I wonder if your coolant for the intercooler is low. This will cause your call to pull timing due to the hot air from the turbos. It may not have hit a point to throw a code.

I’ll check the expansion tanks today

[Mo T.]

Originally Posted by pbonsalb

Resetting adaptions, driving for a bit with 93 or 91 plus some E85, cooler and drier weather, and launch control should help.

Already got the 93 in there, what’s the best way to reset adaptions? I have the WiFi MHD adapter but have yet to buy a BM3 license or MHD license, but I think MHD let’s you reset adaptions for free? Thinking of buying the BM3 for data logging anyway. I guess my concern is if the power loss is excessive.

[pbonsalb]

Datalogs are great for trouble shooting. Most bidirectional scan tools with bmw specific software will reset adaptions. I don’t know what is causing your results, but I would be doing everything I could to rule out problems and to improve the results.

[Mo T.]

Originally Posted by Ropes

I wonder if your coolant for the intercooler is low. This will cause your call to pull timing due to the hot air from the turbos. It may not have hit a point to throw a code.

Both tanks are slightly overfilled actually.

[Ropes]

Interesting 🤔. This was an issue on both my M4 and M5.

[Info@mad-us.com]

Is this your only draggy run or do you have others to compare?

[Kponti]

Normal, I am only a tenth of a second faster than you in an M8 with 2k miles (until I used a blanket)

[Mo T.]

Originally Posted by Info@mad-us.com

Is this your only draggy run or do you have others to compare?

These are the best ones I gathered from that same day, haven’t done any runs again because the weather hasn’t changed

[Mo T.]

Originally Posted by Kponti

Normal, I am only a tenth of a second faster than you in an M8 with 2k miles (until I used a blanket)

In similar DA and humidity? Which turbo blankets do you recommend?

[Kponti]

Originally Posted by Mo T.

In similar DA and humidity? Which turbo blankets do you recommend?

Yes similar temps and DA. I live in Houston, humidity is our middle name.
Let me see if I can find some draggys

[Kponti]

This is after the turbo blanket

[Kponti]

All brake boosted, didn't see the need to waste my launches in this weather especially when it was just to test the effects of the turbo blanket

https://www.ptpturboblankets.com/pro...5-m-x6-m-m5-m6

[pbonsalb]

A top end 60-130 pull difference would be much more convincing. Right now you are showing a bad launch and a vac but not quite as bad launch. You need more than 3 seconds to show significant power loss.

[Kponti]

Originally Posted by pbonsalb

A top end 60-130 pull difference would be much more convincing. Right now you are showing a bad launch and a vac but not quite as bad launch. You need more than 3 seconds to show significant power loss.

Lol did you just say 3 seconds?? You just be trolling right?

[Kponti]

There were no traction issues just hooked and went each run. The car was fully heatsoaked before making a run

[pbonsalb]

Originally Posted by Kponti

Lol did you just say 3 seconds?? You just be trolling right?

You posted 0-60 runs. Can’t tell much about power from those 3 seconds. Try 60-130 to show power gains.

[Mo T.]

Originally Posted by Kponti

There were no traction issues just hooked and went each run. The car was fully heatsoaked before making a run

Do you have any 60-130 runs in conditions similar to mine? @pbonsalb had a point about the 60-130 as a better comparison for power loss between mine and yours