Subtraction by Addition: CHECK! Sometimes I hate my car - Page 3 - The Unofficial BMW M5 Messageboard (m5board.com)

jrhaile · 4th July 2009, 04:01

Okay here is the dyno video but it has 34 minutes left to encode so I guess we'll all have to wait...

BMW E39 M5 Dyno - Reading Low!!! on Vimeo

jt2ma71 · 4th July 2009, 04:33

What MAF numbers are you pulling? I noticed even your traps are a little on the low side considering your mod list. I know watching some of your other videos you were hovering around the 106-107mph range. I thought with those modifcations you have youd be at around 108-109 maybe even 110mph.

When did you replace your pre-cat o2's last? How are your air filters? Have you cleaned them recently? When was the last time you replaced any of your cam sensors? Do you have any codes?

1bad540 · 4th July 2009, 16:25

I was actually wonderig what was wrong with the other M5 you raced. I would have thought he would have jumped on you with the 3.45 gearing.

jrhaile · 4th July 2009, 16:41

Quote:

Originally Posted by jt2ma71

What MAF numbers are you pulling? I noticed even your traps are a little on the low side considering your mod list. I know watching some of your other videos you were hovering around the 106-107mph range. I thought with those modifcations you have youd be at around 108-109 maybe even 110mph.

When did you replace your pre-cat o2's last? How are your air filters? Have you cleaned them recently? When was the last time you replaced any of your cam sensors? Do you have any codes?

Haven't done MAF numbers since changing them out. All O2s were replaced within 5k. Air filters cleaned under 5k ago. All CPS replaced within 5k. No codes

Very well maintained car to say the least...

Quote:

Originally Posted by 1bad540

I was actually wonderig what was wrong with the other M5 you raced. I would have thought he would have jumped on you with the 3.45 gearing.

He's wondering the same as we ran last night again from a 1st gear 10-15mph roll and were yet again, DEAD even.

M5 London · 4th July 2009, 17:01

Hiya,

When you put your bimmerzone MAFS in, did you experience any immediate teething problems like rev hunting, feeling like it might stall, difficult to do parking and turning etc ?

I read someone else experienced this with the bimmerzone ones and to me, this occrured when I put VW MAFS in, but not when I put BMW MAFS in it was immediately GOOD, no so called "learning process" ! I am not saying the bimmerzone ones are the same as VW MAFS (032) but for me it all seems a bit odd !

Please do a MAF test mate ....

xr4tic · 4th July 2009, 18:50

Quote:

Originally Posted by jrhaile

Crap I just realized that he put the wrong run on my graph from today... oh well you still get the point. The one with 326whp and 330ftlbs is from the last session back in May.

Look at your A/F ratio, it's almost a half point lower, then drops even more. That is most likely killing your power.

Isn't the TMS Race Tune made for headers? I don't see that on your mod list, and it may be causing an issue.

I would start by checking your Fuel Trims (OBD2 scanner) and if your pre-cat O2 sensors haven't been changed in a while, I recommend changing them

jrhaile · 5th July 2009, 05:31

Quote:

Originally Posted by xr4tic

Look at your A/F ratio, it's almost a half point lower, then drops even more. That is most likely killing your power.

Isn't the TMS Race Tune made for headers? I don't see that on your mod list, and it may be causing an issue.

I would start by checking your Fuel Trims (OBD2 scanner) and if your pre-cat O2 sensors haven't been changed in a while, I recommend changing them

Pre O2s were replaced within 5k with OEM sensors. As far as the tune, I'm not sure, when I called TMS they told me it can be used with any modified exhaust setups. If this is my issue, I shall be very angry since I called them twice about this

churious · 5th July 2009, 09:53

You should post the video from last nights run...

jt2ma71 · 5th July 2009, 10:21

Yeah, Run the MAF test(l/hr) and what are your long term fuel trims? Even though the Dinan S1 tune apparently doesnt really give much in terms of gains, with those modifications + the TMS id expect atleast 330-340whp.

Then again, assuming that other M5 is running right, i wouldnt look too far into dyno numbers. Again, the dyno operator has inputs, if his/her dyno is not calibrated properly or whatever it can throw the numbers off. I know one of my local dynos which is a dynojet 248c, has a tendancy to under-rate power compared to the normal 248c. The same 335I put out 258whp on that dyno, on the same type of dyno 30 minutes away he put down 271whp, which is right where he should be and make sense with his traps/quater mile times.

Your traps at 106mph did seem a little low, but then again, i think those runs were with the dinan intakes, dinan S1 tune and magnaflow cans, they dont do too much in terms of performance, so i guess its not too far off.

jrhaile · 6th July 2009, 04:11

Quote:

Originally Posted by churious

You should post the video from last nights run...

Just got done AutoXing so I will get it up tonight...