[bimmerquick43321]

Originally Posted by matteblue3er

Drivetrain loss on E9x is about 12-15%.

12% being RWD. 15%, AWD.

So you have about a 30hp loss from crank to wheels, not 50hp.

What were the ambient conditions (temp, barometric pressure, humidity) on the base line dyno run versus after doing the mods? These parameters can affect dyno readings.

I have a 3" diameter hose fitted like you have. Got the snorkel for the OEM airbox from Dinan for $30.

I did have the crush the hose where it goes through the area behind the headlight and frame rail. But it was very little and just barely ovals the hose.

You're not going to be able to fit the 3.5" hose unless you crush it a good bit.

Always thought that for our RWD the driveterrain loss is more ~17% and for the AWD ~19% which would make sense no? A stock 330i will dyno what 215-220whp stock (Edit which after actually doing the math is closer to 15%, so ignore)? Isn't 15% more for fwd?

[hassmaschine]

I prefer to use a smaller number, people will just make up whatever they like. 15% is a good place to start that won't over exaggerate crank HP, for RWD/manual.

I don't think a RWD, manual BMW drivetrain is a 17% loss anyway. 220/255hp is actually really close to 15%. my SAE dyno with a stock tune was about 215whp, which is a little more than 15% loss. but 12% loss? I'd be surprised if it were that efficient.

also, no way an AWD, automatic is only 15% loss.. the transmission alone is probably an extra 5%, not accounting for the programmed torque loss during shifts. the extra friction of 3 extra driveshafts, the transfercase, and the front diff has to be worth a few percent at least.

[tetsuo111]

Originally Posted by mecbain

Always thought that for our RWD the driveterrain loss is more ~17% and for the AWD ~19% which would make sense no? A stock 330i will dyno what 215-220whp stock? Isn't 15% more for fwd?

Had hoped the conversation wouldn't go this direction...

I do remember a dyno on the Official Dyno Thread showing a 328i AWD Steptronic baseline @ ~ 179 HP, forgot the Tq, no mods. Of course I can no longer locate it... Given BMW specs my version N52 @ 230hp, I came up with the number 50.

The meta-point isn't to claim high numbers with precision. The dyno is simply a very rough guide, IMO. The whole point is to show documentation of performance gains resulting from very easy, very inexpensive mods that anyone can do.

I don't really know the drivetrain loss in my car. I made a reasonable assumption based on previous published data. Again, my interest is big-picture trends. I don't know now nor do I have the means to measure with precision actual drivetrain loss.

The meta-point still stands.

[TheSt|G]

Originally Posted by TheAxiom

Why would you do that? We have 3 different dynos showing it adds power.

Originally Posted by hassmaschine

he says his adds an unbearable drone. *shrug*

Indeed. In my setup it absolutely induced drone. I am running Euro intake w/ the Euro BMW Performance intake which is pretty rare however.

Originally Posted by chris82

Feel any power difference with it?

No, but I also only had it on around the block. Even if it gained 5-10hp, that's not something you are likely to feel. Want it?

*Edit* Hell, you are local. You can try it before you buy it if you want.

[hassmaschine]

Originally Posted by tetsuo111

Had hoped the conversation wouldn't go this direction...

I do remember a dyno on the Official Dyno Thread showing a 328i AWD Steptronic baseline @ ~ 179 HP, forgot the Tq, no mods. Of course I can no longer locate it... Given BMW specs my version N52 @ 230hp, I came up with the number 50.

The meta-point isn't to claim high numbers with precision. The dyno is simply a very rough guide, IMO. The whole point is to show documentation of performance gains resulting from very easy, very inexpensive mods that anyone can do.

I don't really know the drivetrain loss in my car. I made a reasonable assumption based on previous published data. Again, my interest is big-picture trends. I don't know now nor do I have the means to measure with precision actual drivetrain loss.

The meta-point still stands.

Agreed. do you have a baseline for your car? I did one for mine, because really it's WHP that matters; you can make up any correction factor you like to calculate BHP... and people often do!

[tetsuo111]

I do get value from the dyno numbers solely for evaluating changes made on my car, if the dyno runs are performed under similar conditions. I get no value from dyno pulls for comparing different vehicles, especially on different dyno machines under different conditions (ambient temp, etc).

Sadly, I don't have a baseline. The June dyno was done to after the first round of power mods (DISA, headers, tune). And this most recent pull served two purposes: 1) satisfies my curiosity about these cheap mods. They're low-hanging fruit. 2) establish a baseline to assess future planned projects.

So, yes I agree. Off topic, thanks for your contributions - I learn much from your posts (although I'm not as tech-savvy as I used to be!)

[bimmerquick43321]

Originally Posted by tetsuo111

Had hoped the conversation wouldn't go this direction...

I do remember a dyno on the Official Dyno Thread showing a 328i AWD Steptronic baseline @ ~ 179 HP, forgot the Tq, no mods. Of course I can no longer locate it... Given BMW specs my version N52 @ 230hp, I came up with the number 50.

The meta-point isn't to claim high numbers with precision. The dyno is simply a very rough guide, IMO. The whole point is to show documentation of performance gains resulting from very easy, very inexpensive mods that anyone can do.

I don't really know the drivetrain loss in my car. I made a reasonable assumption based on previous published data. Again, my interest is big-picture trends. I don't know now nor do I have the means to measure with precision actual drivetrain loss.

The meta-point still stands.

No need to take the discussion in any direction, I didn't say that you were wrong, I just stated what my impression was from what I've heard in general and seen..., I'm not going to argue the contrary if someone here that has experience in dynoing different cars tells me I'm way off.... I would actually like to understand how bmw calculates their bhp versus the whp... or they just don't do dyno runs (in the traditional way) and calculate the power directly at the crank?

[tetsuo111]

Originally Posted by mecbain

No need to take the discussion in any direction, I didn't say that you were wrong, I just stated what my impression was from what I've heard in general and seen..., I'm not going to argue the contrary if someone here that has experience in dynoing different cars tells me I'm way off.... I would actually like to understand how bmw calculates their bhp versus the whp...

Sorry wasn't clear. I simply wanted to gently nudge the conversation away from dyno subject matter to the big picture. Didn't mean to single you out in a disparaging way. Thanks for participating!

[bimmerquick43321]

Originally Posted by tetsuo111

Sorry wasn't clear. I simply wanted to gently nudge the conversation away from dyno subject matter to the big picture. Didn't mean to single you out in a disparaging way. Thanks for participating!

No problem and after looking at the numbers it does seem to be more of a 15% loss indeed for rwd manual.

[hassmaschine]

Originally Posted by mecbain

No need to take the discussion in any direction, I didn't say that you were wrong, I just stated what my impression was from what I've heard in general and seen..., I'm not going to argue the contrary if someone here that has experience in dynoing different cars tells me I'm way off.... I would actually like to understand how bmw calculates their bhp versus the whp... or they just don't do dyno runs (in the traditional way) and calculate the power directly at the crank?

BHP can only be measured at the crank. When BMW develops their engines, they are almost certainly using a highly advanced engine dyno. They do put every car that rolls off the assembly line on a chassis dyno, but this is to make sure that one doesn't come out abnormally low.

I added the silicone intake to mine since my last dyno, but I haven't gone back yet. There's some other stuff I want to tweak first. I don't have headers or any real mods - wonder if I can break 230whp?

[Taskmaster]

Originally Posted by hassmaschine

BHP can only be measured at the crank. When BMW develops their engines, they are almost certainly using a highly advanced engine dyno. They do put every car that rolls off the assembly line on a chassis dyno, but this is to make sure that one doesn't come out abnormally low.

I added the silicone intake to mine since my last dyno, but I haven't gone back yet. There's some other stuff I want to tweak first. I don't have headers or any real mods - wonder if I can break 230whp?

Dyno thread has a few tune only (with slight intake mods) cars with over 23Xwhp, including my most recent post.

[matteblue3er]

Originally Posted by mecbain

Always thought that for our RWD the driveterrain loss is more ~17% and for the AWD ~19% which would make sense no? A stock 330i will dyno what 215-220whp stock (Edit which after actually doing the math is closer to 15%, so ignore)? Isn't 15% more for fwd?

Drivetrain loss has nothing to do with configuration. It's about weight and efficiency.

I've found these cars to make power around there. Some may dyno higher or lower but I think 12-15% is pretty average.

[bimmerquick43321]

Originally Posted by matteblue3er

Drivetrain loss has nothing to do with configuration. It's about weight and efficiency.

I've found these cars to make power around there. Some may dyno higher or lower but I think 12-15% is pretty average.

by configuration you mean fwd vs rwd vs awd than yes it does have something to do with the % of drive terrain loss, unless you're trying to say the same thing from another perspective, in regards to "efficiency". I

[hassmaschine]

Originally Posted by matteblue3er

Drivetrain loss has nothing to do with configuration. It's about weight and efficiency.

I've found these cars to make power around there. Some may dyno higher or lower but I think 12-15% is pretty average.

What? It absolutely has to do with the drivetrain layout. The weight of the car has zero to do with it.

[matteblue3er]

Originally Posted by mecbain

by configuration you mean fwd vs rwd vs awd than yes it does have something to do with the % of drive terrain loss, unless you're trying to say the same thing from another perspective, in regards to "efficiency". I

Originally Posted by hassmaschine

What? It absolutely has to do with the drivetrain layout. The weight of the car has zero to do with it.

I am not referring to vehicle weight. I am referring to drive train component weight/efficiency....driveshaft, half shafts, diffs/gearing, trans/gearing, etc.

The point I was trying to make is that you cannot base drivetrain loss on configuration (RWD vs FWD vs AWD). There are MANY factors that dictate drivetrain loss. It will be different for every make and model.

It sounded like you were basing your drivetrain loss solely on how the drivetrain was configured.

[hassmaschine]

Im not sure what your point is. An AWD E90 certainly has more loss than a RWD one. As does an automatic.

Its way off topic now anyway.. Sorry OP.

[matteblue3er]

Originally Posted by hassmaschine

Im not sure what your point is. An AWD E90 certainly has more loss than a RWD one. As does an automatic.

Its way off topic now anyway.. Sorry OP.

lol you don't get what I am saying at all and just spitting out obvious info

[Taskmaster]

Originally Posted by matteblue3er

lol you don't get what I am saying at all and just spitting out obvious info

Not to be rude, but I don't either.

[bimmerquick43321]

Originally Posted by matteblue3er

lol you don't get what I am saying at all and just spitting out obvious info

it's because you're not explaining it clearly enough...
I get it you're saying the same thing but from another perspective, like saying that the generated mass by the different drive terrain components will affect the driveterrai loss, yes... but as much as it means that 2 awd systems wont necessarely have the same driveterrain loss, it also means that obviously an awd system which has more mass, will lose more power...... same thing different way of saying it... nobody here is stupid and saying that only awd fwd rwd will have an impact ONLY, but they play a major role

[matteblue3er]

First of all, there are no FWD, E9x configurations.

So why FWD was even thrown into the equation, I have no idea.

By your logic, a FWD Mini Cooper has the same drivetrain loss as a FWD Honda Accord?

No, because the drivetrain component's weight and efficiency between the 2 models are different...

[hassmaschine]

Just stop.

[refugeeofwar]

Originally Posted by mecbain

No need to take the discussion in any direction, I didn't say that you were wrong, I just stated what my impression was from what I've heard in general and seen..., I'm not going to argue the contrary if someone here that has experience in dynoing different cars tells me I'm way off.... I would actually like to understand how bmw calculates their bhp versus the whp... or they just don't do dyno runs (in the traditional way) and calculate the power directly at the crank?

Getting crank power is easy. You simply hook a engine dyno up to the flywheel before putting the engine in a car.