low numbers on Dyno?

I took my car in to EAS this past friday to dyno my car. Got lower numbers than i expected. As you can see in my power curve, in-particular the high rpm, it seems there is a small dip in power. Not sure why it would do that with the Dinan stage III tune. Called Dinan and they said it's most likely not getting enough airflow depending on the fan used.Looking for some feedback from you guys on opinions why i made these numbers and why im hittin that dip in power towards the top. I will post up afr and climate stats as soon as i get the paperwork from EAS. Dyno run was done in 3rd gear.

2002 e46 m3 with SMG. 112k miles. Maintained like a Queen.
mods:
dinan stage III tune
Dinan cat-back exhaust
Dinan high flow mass meter/intake
Dinan throttle bodies

I can't see your dyno sheet (blocked while I'm at work) but it's normal to get a small dip around 4,000 RPM.

Originally Posted by LivesNearCostco

I can't see your dyno sheet (blocked while I'm at work) but it's normal to get a small dip around 4,000 RPM.

mine dipped at about 6500rpm or so.

I know you're in a M3 because of the 8000 RPM cutoff, but forum members like you frustrate me, why ? Because you make everyone guess at what you're driving.

Maybe your ride is really a Mazda RX7.

You need to tell everyone all of the car details:

1) Year ?

2) Model ?

3) Transmission ?

4) Mods, when you say "Dinan exhaust", is there a header in this statement ?

5) Dyno, gear used (3rd or 4th)

6) AFR ?


With all of the facts, the E46F community can possibly help you. Without, we can not.


Good luck.

Originally Posted by Rob43

I know you're in a M3 because of the 8000 RPM cutoff, but forum members like you frustrate me, why ? Because you make everyone guess at what you're driving.

Maybe your ride is really a Mazda RX7.

You need to tell everyone all of the car details:

1) Year ?

2) Model ?

3) Transmission ?

4) Mods, when you say "Dinan exhaust", is there a header in this statement ?

5) Dyno, gear used (3rd or 4th)

6) AFR ?


With all of the facts, the E46F community can possibly help you. Without, we can not.


Good luck.

I thought i was posting in the e46 m3 forum. My bad. As you can see, i just joined this forum. I'll update my user cp with my car details. Nothing to get frustrated over. Be happy.

You're posting on an e46 forum. Quite a few flavors, very different performance. If my 330 was putting down numbers like that, I definitely wouldn't be complaining.

Although, good to know you don't have much on my in the way of torque

Originally Posted by sambona

I thought i was posting in the e46 m3 forum. My bad. As you can see, i just joined this forum. I'll update my user cp with my car details. Nothing to get frustrated over. Be happy.

Originally Posted by aggieE46

Although, good to know you don't have much on my in the way of torque

stop bragging Brady. jkjk!

That's an interesting dyno though. It could definitely be a problem with airflow. What kinda numbers were you expecting?

I don't think that's too far off. Most E46 M3s dyno somewhere between 260 and 290 stock as far as I'm aware. I've also read that the E46 M3 "knows" when it's on a dyno and pulls back timings a bit (dunno if that's just people trying to justify what appears to be an inefficient drivetrain, but it wouldn't surprise me considering the crap you have to do to get the car in "dyno mode")

My apologies for saying it's normal to have a dip at 4,000 RPM. It is... for an E46 330 with the M54 engine. I didn't know you had the S54 engine.

That said, if the spec crank HP is 330 and you assume 15% drivetrain loss, you're right on the money at 280 RWHP. If we assume drivetrain loss is really 18%, then 280 HP to the wheels means 341HP at the crank and you can say your mods gave you 11 extra peak HP at the crank compared to stock. Do you also have Dinan software?

I'm no dyno expert, but now that I can see your sheet, why does it say correction factor = STD instead of SAE? What is the difference?

Interesting. 328i's are putting down 240/275 stock now.

Originally Posted by SL Blak Soldier

stop bragging Brady. jkjk!

That's an interesting dyno though. It could definitely be a problem with airflow. What kinda numbers were you expecting?

if it's rated 333hp at crank, i figured at least 20hp gain from my mods, so a little over 300hp was my goal.

Originally Posted by TerraPhantm

I don't think that's too far off. Most E46 M3s dyno somewhere between 260 and 290 stock as far as I'm aware. I've also read that the E46 M3 "knows" when it's on a dyno and pulls back timings a bit (dunno if that's just people trying to justify what appears to be an inefficient drivetrain, but it wouldn't surprise me considering the crap you have to do to get the car in "dyno mode")

yea 260-290hp is stock but if you notice in the high rpm, i get power loss. Dyno operator suggested the car was pulling timing so i imagine without that dip, i would make more peak power up top. Tell me more about this "dyno mode." The dyno operator didnt really do much more than tying down the car and putting the fan on it.

Originally Posted by LivesNearCostco

My apologies for saying it's normal to have a dip at 4,000 RPM. It is... for an E46 330 with the M54 engine. I didn't know you had the S54 engine.

That said, if the spec crank HP is 330 and you assume 15% drivetrain loss, you're right on the money at 280 RWHP. If we assume drivetrain loss is really 18%, then 280 HP to the wheels means 341HP at the crank and you can say your mods gave you 11 extra peak HP at the crank compared to stock. Do you also have Dinan software?

I'm no dyno expert, but now that I can see your sheet, why does it say correction factor = STD instead of SAE? What is the difference?

Yes, i have a dinan stage III tune. Most m3's stock put down around this much depending on variables so that is why i assume these are low numbers.

I too didnt know what the difference was but i did find this:
"This is from a magazine article on "dynojet" dynos.

SAE j1349 correction:
29.23 in/hg.
77 degree temp
0 percent humidity

Standard correction:
29.92 in/hg.
68 degree temp
0 percent humidity

What this all means is that "Standard" will give you 2.6 percent better numbers (very popular for the import crowd). The example the magazine gave was a Vette making 412 (SAE corrected hp). With the Standard correction it made 423. All that you will have to do is multiply your "Standard rwhp" by .974 This should equal SAE (the one everyone uses). Up here in the great white North (Washington) the temps are in the 40-50 degree area, along with 29.9-30 in/hg. So, our numbers are actually corrected down from what it made at the rear. Usually, 96-97 percent of actual posted numbers. If you dyno when it's a hotter temp or higher altitudes the numbers will usually correct up to equal the desired temp, humidity and pressure of the correction factor. "

http://ls1tech.com/forums/gears-axle...fferences.html

Without a stock baseline, everything is pretty much speculation.

Stock e46M3 have been known to be all over the place, I've seen some dyno as high as 300whp stock.

Originally Posted by tom @ eas

Without a stock baseline, everything is pretty much speculation.

Stock e46M3 have been known to be all over the place, I've seen some dyno as high as 300whp stock.

True story. What im really more concerned about it the dip in power at high rpm and what to do to fix that.

Originally Posted by sea6speed

Interesting. 328i's are putting down 240/275 stock now.

Totally inconclusive. Dynos read all over the map. Also that's one of the highest I've heard, they mostly are dyno-ing in the 230-240s.

Originally Posted by sambona

True story. What im really more concerned about it the dip in power at high rpm and what to do to fix that.

Easiest comparison would be to dyno again with stock software.

I would call Dinan beforehand to see if there is any charge for reflashing if needed.