AFM relocation
#2
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Slightly better turbo response. But you must change certain things in the chip to compensate.
#5
Temprarily Banned per IB
I believe it was BMW that chose the location, not Bosch. Interesting setup. I think I would go one step farther and run a pipe from the turbo down in front of the passenger side wheel well and put the filter there. Some fellows have done that with the 951s. I can't really see the passenger side in front of the turbo, do you have a duct over there feeding air straight to the filter?
Regards,
Russell
Regards,
Russell
#6
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Join Date: Jul 2006
Location: Fort Worth, TX
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I relocated it in my headlight bucket and drilled a hole through...then placed the filter below...before the mod the car was running 20psi getting 235 rwhp and 258 ft-lbs...afterwards I decreased the boost to 15psi...where it was supposed to be in the first place and with the new intake setup achieved 253 rwhp and 250 ft-lbs...so I gained 15 rwhp with 5 lbs less boost...but my torque dropped off slightly...probably due to the 5psi decrease in boost...overall i can actually feel the difference in the pull because i'm getting a much more linear power response...I would run it at 20 psi...but it should never have been run there in the first place...
#7
Three Wheelin'
Is that your car? That looks like a serious top mount turbo!
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#8
Race Car
Thread Starter
I believe it was BMW that chose the location, not Bosch. Interesting setup. I think I would go one step farther and run a pipe from the turbo down in front of the passenger side wheel well and put the filter there. Some fellows have done that with the 951s. I can't really see the passenger side in front of the turbo, do you have a duct over there feeding air straight to the filter?
Is that your car? That looks like a serious top mount turbo!
I have not seen any factory car with Motronic/AFM hooked that way. Seems to me many BMW owners does it that way. I have seen maybe about 5-6 years ago here on Rennlist a pictures of a 951 which has AFM connected similar way.
#9
Can this really work?
My understanding is that the AFM measures a volume stream (m3/h). It does not measure any density of the air (kg/m3). It should be difficult to adjust the DME with changing boost levels.
This should work with a MAF that measures the mass of the air stream (kg/h) and is able to compensate the changing air density.
Bosch placed the AFM in turbo applications on the atmospheric side to get a constant air density.
My understanding is that the AFM measures a volume stream (m3/h). It does not measure any density of the air (kg/m3). It should be difficult to adjust the DME with changing boost levels.
This should work with a MAF that measures the mass of the air stream (kg/h) and is able to compensate the changing air density.
Bosch placed the AFM in turbo applications on the atmospheric side to get a constant air density.
#10
Three Wheelin'
Well, it will work ok under boost... the afm door just blows right open.
It's ok for low boost/ low power applications, but that setup will never allow that turbo to realize its full potential.
Get an aftermarket fuel/timing setup and it will make a big difference
It's ok for low boost/ low power applications, but that setup will never allow that turbo to realize its full potential.
Get an aftermarket fuel/timing setup and it will make a big difference