[cam_lg]

Originally Posted by rader1

Here's a plot of your datalogs you posted last night.

This is kind of odd because datalog 4 has HORRIBLE timing corrections but datalog 5 has ZERO corrections.

Based on your logs i assuming youre running the sport map, correct?

The first chart is datalog 4 then datalog 5. The last graph is comparing your datalog 4 stage 2+ sport to my stage 2+ sport dyno. You're WAY down on power for some reason.

Thanks for helping me graph it man, and yup I'm running the sport map with CA 91 gas.
On the virtual dyno stats I don't know if it makes a difference but I've got a 335, not a 135, but I don't think that would grant a 42 horsepower loss...
And I'm pretty sure it's not intake valves the most I've seen from cleaning them is like 10 horses...

[rader1]

Originally Posted by cam_lg

Thanks for helping me graph it man, and yup I'm running the sport map with CA 91 gas.
On the virtual dyno stats I don't know if it makes a difference but I've got a 335, not a 135, but I don't think that would grant a 42 horsepower loss...
And I'm pretty sure it's not intake valves the most I've seen from cleaning them is like 10 horses...

Yeah, i dont see the difference beeing 40hp. Not only that but i weigh 220lbs and have stuff in the trunk and i added that into the vehicle weight, so the weight difference probably isnt that much,

[cam_lg]

So does nobody else have an idea of what could be wrong?...

[cam_lg]

nobody...? should i bring it to an actual dyno maybe?

[rader1]

Originally Posted by cam_lg

nobody...? should i bring it to an actual dyno maybe?

I think that would be a good idea. Get a dyno of stage 2+ and of map 0.

I've spent the last half hour going over your logs and you SHOULD be making power than you are. Timing and boost are both where they should be. Requested and actual load are where they should be. You're having no throttle closures. I don't get it

[benzy89]

While the logs are illustrating that the engine is performing right, have we considered that something might be wrong w/ the drivetrain. If the power isn't being properly delivered to the wheels, then he could be making 1,000 HP and it won't matter.

It might be possible that you' have a broken axle shaft and there's no power being delivered to one wheel... I don't know, just throwing out a new theory since the engine seems to be performing fine.

[cam_lg]

so i was just reading that when some people install their downpipes the v-band clamps can get in the way of the waste gate and either hold it from closing all the way or keep it from opening... colud that be the problem?
I figured I'd atleast be able to hear them if they were open at idle tho, and I would have trouble hitting boost targets. but idk..

[rader1]

Originally Posted by cam_lg

so i was just reading that when some people install their downpipes the v-band clamps can get in the way of the waste gate and either hold it from closing all the way or keep it from opening... colud that be the problem?
I figured I'd atleast be able to hear them if they were open at idle tho, and I would have trouble hitting boost targets. but idk..

No, I don't think so. You're hitting your boost target just fine and you would more than likely trigger an under boost code if that was going on.
I also don't think its a clutch problem because your RPMs climb smoothly and steadily.

[Sered]

Originally Posted by 135i

Driver mod.

He's got 1mph over a stock car?

[Markyd83]

Does your car feel faster than it did stock?

[Nigelo]

I'm a bit of a newb, but what would be the outcome if the engine was down on compression for some reason? If the boost target is met, the O2 is there, the fuel must be there as well to keep afr in check, so just trying to think what else could reduce power.

[cam_lg]

I guess I'll try flashing it back to stock and use cobb as the 1/4 test then run it again with the stage 2+ map and see if it changes anything... Also as a bit of a side note my friends gto that I roll race once in a while does the quarter at 13.1 @ 108 and pulls me on the highway all the time with my stage 2 +

[benzy89]

Originally Posted by cam_lg

nobody...? should i bring it to an actual dyno maybe?

It might be possible that you' have a broken axle shaft and there's no power being delivered to one wheel. Your engine appears to be performing fine so I think you should start exploring other possibilities.

[cam_lg]

Originally Posted by benzy89

It might be possible that you' have a broken axle shaft and there's no power being delivered to one wheel. Your engine appears to be performing fine so I think you should start exploring other possibilities.

Ok just jacked up the car and spun both wheels and saw the driveshaft spinning when I turned each wheel... So I don't think it's an axel plus the both looked fine no leaks or cracks or anything.

However when I spun one wheel the other did not turn and visa versa idk if that's just how open diffs work, I assumed when you spun one side foreword the other would move backwards tho..?

[Sered]

Originally Posted by benzy89

It might be possible that you' have a broken axle shaft and there's no power being delivered to one wheel. Your engine appears to be performing fine so I think you should start exploring other possibilities.

WTF?

[benzy89]

Originally Posted by Sered

WTF?

Some1 who did an LSD upgrade didn't even realize why their car wasn't deliverying full power until they realized they had sheared an axle shaft. It's not a common problem, but the BMW drivetrain isn't built like a Mustang or Camaro's where it can handle the repeated stress of drag strip racing.

[statelax3]

Originally Posted by cam_lg

However when I spun one wheel the other did not turn and visa versa idk if that's just how open diffs work, I assumed when you spun one side foreword the other would move backwards tho..?

this is normal. no lsd.

[Jeff@TopGearSolutions]

Originally Posted by cam_lg

Ive got Apex arc 8 wheels, I'm about 180 pounds with no more then 10 pounds of random stuff in my trunk, no subs, no I-drive, windows up and shifting at about 6200 rpm's.

Might want to try shifting around 6400-6500. But this thread is interesting. I'm sure an intake valve cleaning would help but I dont think it would help that much, especially if everyone says the logs look good.

Perhaps you are down on compression?

Have we determined that the following are correct:

Intake air temps not going over 140 F
No timing drop outs and ignition rising to redline
Boost hitting taget and no throttle closures
Wastegate duty cycle within normal tolerances

[Sered]

Originally Posted by benzy89

Some1 who did an LSD upgrade didn't even realize why their car wasn't deliverying full power until they realized they had sheared an axle shaft. It's not a common problem, but the BMW drivetrain isn't built like a Mustang or Camaro's where it can handle the repeated stress of drag strip racing.

Sheering an axle shaft, breaking drivetrain parts, etc is VERY noticeable. I can't even fathom how someone could miss that. That's on the level of draining your oil while the engine is running.

[Bash]

This is all based that your friend's gto is faster than your car??? Or virtual dyno?
A lot of assumptions, just Dyno it and put an end to the guessing game.

[cam_lg]

Originally Posted by Bash

This is all based that your friend's gto is faster than your car??? Or virtual dyno?
A lot of assumptions, just Dyno it and put an end to the guessing game.

And trap speed at the strip... But I'm planning on going to a dyno in the next few weeks...

[Jeff@TopGearSolutions]

Originally Posted by cam_lg

And trap speed at the strip... But I'm planning on going to a dyno in the next few weeks...

Did you got to the track again, if I recall you had a 2.4 60 foot.

It would be a better measurement of power if you cut a 1.9 or 2.0 at worst. Your trap speed would then be higher. This car needs traction for a nice trap speed.

Also proper shift points would help too.