Dyno (AAECU-AAPLLY-AAFilter) - Before & After [Something Wrong??]

[Ado]

Hmmm thanks for noticing that spike. I'll have to check out the other runs I did and see if I can find one run without the spike. The other two runs were very similar #'s. I'm in daytona ATM so don't have them on me.

The runs were done on seperate days. I did the moded run 2 days after having mode installed.

Thanks for the help.

[jml]

Seems about right. You changed the air filter and dropped the accessory load. The main accessory load is the A/C and Alternator, both of which are not even drawing a load most of the time in the M3. I think this is an old argument, but as an engineer I have to believe it - if there was 10 HP on the table with a $5 air filter part, you think BMW would have incorporated it into the design.

Get rid of both sets of cats. On the E46, cats in the headers were the bottle neck, easily 20Hp with just headers and a tune that allows a more aggressive map. A cat is a constraint the engineers had to work with. Remove the constraint....sure I can believe more power is possible.

[SECRET M]

i recall reading that the car is design so that accessory load is reduced during heavy acceleration. not sure how exactly this is done though, but i'm curious how this changes the effectiveness of the AC and alternator pulleys.

[jml]

Originally Posted by SECRET M

i recall reading that the car is design so that accessory load is reduced during heavy acceleration. not sure how exactly this is done though, but i'm curious how this changes the effectiveness of the AC and alternator pulleys.

The A/C compressor clutch opens at WOT. The Alternator draws a load mostly under deceleration (BMW marketing geniuses call that regenerative braking).

Water pump and PS are really the only accessories for which pulleys can reduce power usage.

[dcstep]

349 stock on a Dynojet is strong. Look at PencilGeek's collection of dyno runs. Most are getting around 330 for stock.

Usually you get three pulls in a typical baseline run. If you did, lay them on top of each other and if the shape of one is different from the others don't use it, because something happened with the drums. The hp may vary a little but the shape of the curves should be very close.

Anyway, those are strong numbers. Does that shop have runs for any other E9x M3? If so, you might see if they'll share the baselines to see how yours compares.

Dave

[gemini330zhp]

I think all dynos are not created equal. If you want power get a SC...or save up and get the Dinan 4.6 liter.

[Ado]

Dinan 4.6 liter?

[J08M3]

Originally Posted by jml

Seems about right. You changed the air filter and dropped the accessory load. The main accessory load is the A/C and Alternator, both of which are not even drawing a load most of the time in the M3. I think this is an old argument, but as an engineer I have to believe it - if there was 10 HP on the table with a $5 air filter part, you think BMW would have incorporated it into the design.

+1

This is why I won't be buying a pulley.

[powertrip]

Originally Posted by J08M3

+1

This is why I won't be buying a pulley.

You'll be missing out . I have a noticed a very nice difference in low-mid power with my new pullies. The car is much more responsive .

[m34jlp]

Originally Posted by Active Autowerke

You have a STOCK exhaust with cats cut out. Its like blowing through a straw and still having restriction at the end, it cancels everything out.

I understand that, but I have yet to see anyone not get any power from removing the cats completely (regardless of stock muffler or not), tune, and filter...unless my engine is really that low on power...just doesn't add up.