Dyno'ed my M3 with and without RPI Air Scoops... results:

[Sticky]

Originally Posted by swamp2

1. In my opinion this is the responsibility of the vendor and or the users of the product. As we all know it has been skirted.
2. Although it would be a very fun/interesting/useful exercise, I simply don't have enough interest in this.

Skirted? If you are going to say something like that, back it up. The only data you don't have on these so far would be the datalogging, dyno numbers and 1/4 mile times exist.

In my opinion, from all the vendors I have dealt with, RPI is the most honest and down to earth. They are also consistently offering the best prices on products for us BMW guys.

[swamp2]

Originally Posted by Sticky

Skirted? If you are going to say something like that, back it up. The only data you don't have on these so far would be the datalogging, dyno numbers and 1/4 mile times exist.

In my opinion, from all the vendors I have dealt with, RPI is the most honest and down to earth. They are also consistently offering the best prices on products for us BMW guys.

Why do I have to back up a factual statement? The vendor of the product has not provided an instrumented, apples to apples comparison with multiple runs measuring acceleration on a single car with the only change being the scoops. No one has done this vendor, customer or 3rd party. This is absolutely not an attack on them, just to make that clear.

We beat the horse plenty bloody on the topic of evidence threshold and no doubt yours is lower than many other members here with regards to intake mods. That is fine, just realize we all have different standards.

[kmac1980]

Originally Posted by Sticky

He's one of those people who thinks if you can gain power BMW would have already done it. He doesn't know jack about modding M cars, don't worry about it.

while BMW doesnt do everything to their cars for max power, their engineers are well aware of what could be done to squeeze every last ounce of performance out of these cars, however they look at the whole performance vs. cost, reliability, comfort etc.. equation and put the car out at its current performance because of that carefully measured equation, not because that was the best they could do!

so i agree modding will advance the car if either you buy parts made of exotic materials like titanium, CF etc (that wouldnt be cost effective in the stock vehicle), or you are willing to sacrifice comfort or fuel economy or daily driveability etc....

im pretty sure the top engineers working on M cars at BMW are more skilled than the ones working for 99% of tuners...

[dcstep]

When I did my baseline runs on a Dynojet the other day the runs varied from 328 corrected rwhp to 333 rwhp, increasing with each run, as heat built in the engine, as expected (oil temp went up about 10-degrees, starting slightly low and ending slightly high). Even averaging five runs and comparing that to the average of five baseline runs, a 2 hp "gain" would be inconclusive, IMHO.

Dave

[aus]

Couldn't someone do a few rolling starts with a GTech with and without scoops to see if there's a difference? Or if you have DCT and are willing to trash the tranny, do a few runs with and without the scoops? Wouldn't that be real world airflow?
If a few cars showed improved pulls, that would be pretty convincing.

[Sticky]

Originally Posted by kmac1980

while BMW doesnt do everything to their cars for max power, their engineers are well aware of what could be done to squeeze every last ounce of performance out of these cars, however they look at the whole performance vs. cost, reliability, comfort etc.. equation and put the car out at its current performance because of that carefully measured equation, not because that was the best they could do!

so i agree modding will advance the car if either you buy parts made of exotic materials like titanium, CF etc (that wouldnt be cost effective in the stock vehicle), or you are willing to sacrifice comfort or fuel economy or daily driveability etc....

im pretty sure the top engineers working on M cars at BMW are more skilled than the ones working for 99% of tuners...

Of course they are more skilled, but they did not squeeze every last ounce of performance out of the cars. They can't, the cars have to meet regulations.

The CSL was rumored to be in the 470 hp range, seems they could find plenty of HP left on the table. The E46 M3's intake system was revised for the CSL, just because something comes from the BMW engineers does not mean they themselves made it to the maximum level they are capable of. They are able to improve on their own designs of cars developed to an extremely high level, like the M3.

My car makes far more power than a stock M3, what sacrifices? What exotic materials?

[FStop7]

BMW squeezed more from the S54 by switching to a better intake design, going from mass air to Alpha-N, improving the headers, and using hotter cams. There's no reason they couldn't do all of the above to get more power from the S65 (except IIRC the S65 is already Alpha-N)

[Sticky]

Originally Posted by swamp2

Why do I have to back up a factual statement? The vendor of the product has not provided an instrumented, apples to apples comparison with multiple runs measuring acceleration on a single car with the only change being the scoops. No one has done this vendor, customer or 3rd party. This is absolutely not an attack on them, just to make that clear.

We beat the horse plenty bloody on the topic of evidence threshold and no doubt yours is lower than many other members here with regards to intake mods. That is fine, just realize we all have different standards.

Uh, I have taken my car to the strip before the scoops and after the scoops.

Thing is, they were different strips and I added a cat delete as well. I went from a 12.7@111 before the scoops and cat delete and to a 12.1@115 with. I have run my friends STI with the scoops and without the scoops. His car turns an 11.9@115, without the scoops he beat me down low and up top. With them, I pull him up top.

If that isn't real world testing, I don't know what is. I know first hand they make a difference, others don't, but that is fine, their loss.

[Sticky]

Originally Posted by FStop7

BMW squeezed more from the S54 by switching to a better intake design, going from mass air to Alpha-N, improving the headers, and using hotter cams. There's no reason they couldn't do all of the above to get more power from the S65 (except IIRC the S65 is already Alpha-N)

Bingo...

[kmax1980]

Originally Posted by Sticky

Of course they are more skilled, but they did not squeeze every last ounce of performance out of the cars. They can't, the cars have to meet regulations.

The CSL was rumored to be in the 470 hp range, seems they could find plenty of HP left on the table. The E46 M3's intake system was revised for the CSL, just because something comes from the BMW engineers does not mean they themselves made it to the maximum level they are capable of. They are able to improve on their own designs of cars developed to an extremely high level, like the M3.

My car makes far more power than a stock M3, what sacrifices? What exotic materials?

fuel economy, emissions, long term reliabilty of chipping (unknown i'd say at best), accessories not being driven at optimal level (if you have an underdrive pulley), but to many people on this board fuel economy is not important....I just don't see how you can get much more power without more fuel/air!...

and again as i said before, pricepoint....CSL components to generate 470hp wouldnt be viable on a base m3 pricepont vehicle... im sure they could get 500hp out of the platform for lots more $$$

it's also well known that CSL models tend to sacrifice creature comforts and ride quality... because their target market is more performance oriented. keep in mind BMW sells many M cars to folks who want performance, but also want decent fuel mileage (more importantly range) and a reasonably comfortable ride, cushy leather, air-conditioning, premium sound, airbags galore etc..

[swamp2]

Originally Posted by Sticky

Uh, I have taken my car to the strip before the scoops and after the scoops.

Thing is, they were different strips and I added a cat delete as well. I went from a 12.7@111 before the scoops and cat delete and to a 12.1@115 with. I have run my friends STI with the scoops and without the scoops. His car turns an 11.9@115, without the scoops he beat me down low and up top. With them, I pull him up top.

If that isn't real world testing, I don't know what is. I know first hand they make a difference, others don't, but that is fine, their loss.

You are joking right? You managed to get one criteria here, "real world" but as is painfully obvious, you have completely missed the "apples to apples" part. Classic modder phenomena make a lot of changes and then test and make some conclusions about each change. Sorry sticky but that is pure foolishness. Why do I feel like I am beating my head against a brick wall? You know it is not apples to apples in your own admission.

Is the STI comparison apples to apples vs. your car? Can you quantify "pull on him up top". I know what it means but how large is the effect, larger or smaller than noise (just like 2 hp is noise)?

[Sticky]

Originally Posted by swamp2

You are joking right? You managed to get one criteria here, "real world" but as is painfully obvious, you have completely missed the "apples to apples" part. Classic modder phenomena make a lot of changes and then test and make some conclusions about each change. Sorry sticky but that is pure foolishness. Why do I feel like I am beating my head against a brick wall? You know it is not apples to apples in your own admission.

Is the STI comparison apples to apples vs. your car? Can you quantify "pull on him up top". I know what it means but how large is the effect, larger or smaller than noise (just like 2 hp is noise)?

Look, I did not take a scientific approach to modding my car to prove things to you. I did not dyno the car at every stage along the way. I modded my car to serve my purposes, not yours. I feel I have a much greater hands on grasp as to the difference the scoops make than most. As I said, if I just put in scoops by themselves it would be obvious. I didn't, so I mentioned it, come to your own conclusion.

Yes, I can quantify pull up top. The STI is apples to apples because I know exactly what he runs at the same track, same time, the amount of boost he is pushing, what setup, and that the setup has not changed. It is as close to a constant for me to base against as I can consistently get.

Pull up top, in this case, is that by 100 I am a car length+ ahead and the increase continues progressively. Before the scoops, it would be reversed.

[Sticky]

Originally Posted by kmax1980

fuel economy, emissions, long term reliabilty of chipping (unknown i'd say at best), accessories not being driven at optimal level (if you have an underdrive pulley), but to many people on this board fuel economy is not important....I just don't see how you can get much more power without more fuel/air!...

and again as i said before, pricepoint....CSL components to generate 470hp wouldnt be viable on a base m3 pricepont vehicle... im sure they could get 500hp out of the platform for lots more $$$

it's also well known that CSL models tend to sacrifice creature comforts and ride quality... because their target market is more performance oriented. keep in mind BMW sells many M cars to folks who want performance, but also want decent fuel mileage (more importantly range) and a reasonably comfortable ride, cushy leather, air-conditioning, premium sound, airbags galore etc..

Long term reliability is not known? Where you have you been? Have you looked at the S54?

So now you are saying they can get more power, but for more money? A bit of a shift.

Sacrificing creature comforts is to improve performance due to removing weight. What exactly does that have to do with the CSL motor making more power from the same powerplant? The point, since you missed it, is that there is headroom even in a 100 hp per liter motor. The other point is that if modding an M3 you don't have to sacrifice creature comforts, unless you want to.

[kmax1980]

actually if you look at my original post you will notice I mention "performance vs. cost" some people forget BMW is in the business of producing MASS MARKET vehicles that sell in numbers and have PROFIT MARGINS, so don't try to argue that BMW set out to build the ultimate vehicle at all costs, and this is the best they came up with....then months after it's release, a few 10person shop tuners managed to develop groundbreaking mods that unlocked the true potential of the platform leaving the folks in Munich jaws dropped....

and you still haven't addressed the fact that there are people (such as myself) that prefer not having to fill up every 200miles... how do you intend to bump your power output significantly without using more fuel? if you tell me that BMW engineers didn't factor fuel economy into the equation you are dreaming. also, im not sure about an ECU tune, but if you remove your Cats you are certainly going to be failing any emissions test and your car is technically not even street legal (not that most people care, but it is the principal of it)

Originally Posted by Sticky

Long term reliability is not known? Where you have you been? Have you looked at the S54?

So now you are saying they can get more power, but for more money? A bit of a shift.

Sacrificing creature comforts is to improve performance due to removing weight. What exactly does that have to do with the CSL motor making more power from the same powerplant? The point, since you missed it, is that there is headroom even in a 100 hp per liter motor. The other point is that if modding an M3 you don't have to sacrifice creature comforts, unless you want to.

[Sticky]

Originally Posted by PencilGeek

How do you guarantee that the wind conditions are idential between successive runs?

You rent a blimp hanger.

[Sticky]

Originally Posted by kmax1980

actually if you look at my original post you will notice I mention "performance vs. cost" some people forget BMW is in the business of producing MASS MARKET vehicles that sell in numbers and have PROFIT MARGINS, so don't try to argue that BMW set out to build the ultimate vehicle at all costs, and this is the best they came up with....then months after it's release, a few 10person shop tuners managed to develop groundbreaking mods that unlocked the true potential of the platform leaving the folks in Munich jaws dropped....

and you still haven't addressed the fact that there are people (such as myself) that prefer not having to fill up every 200miles... how do you intend to bump your power output significantly without using more fuel? if you tell me that BMW engineers didn't factor fuel economy into the equation you are dreaming. also, im not sure about an ECU tune, but if you remove your Cats you are certainly going to be failing any emissions test and your car is technically not even street legal (not that most people care, but it is the principal of it)

I don't know where you came up with that I was arguing BMW came up with the ultimate vehicle.

You are going to hang on to the fuel economy aspect as that is all you left. However, it depends where you are making this power and how. A tune can under less throttle load produce better mileage. A tune can lean the car out a bit, allowing it to burn better the fuel it is already using. There are many variables.

Regarding cats, depends which set you remove and when you test. You CAN pass with one set of cats.

[swamp2]

Originally Posted by Sticky

Look, I did not take a scientific approach to modding my car to prove things to you. I did not dyno the car at every stage along the way. I modded my car to serve my purposes, not yours.

You sure do an immense amount of defense of your decisions and this product if you have nothing to prove to me nor to others. I don't have anything to prove myself, I just like solid claims with solid evidence and dislike the opposite.

Originally Posted by Sticky

As I said, if I just put in scoops by themselves it would be obvious. I didn't, so I mentioned it, come to your own conclusion.

On the aforementioned piece of "evidence" and whether or not it is apples to apples I certainly have come to my own conclusion.

Originally Posted by Sticky

Yes, I can quantify pull up top. The STI is apples to apples because I know exactly what he runs at the same track, same time, the amount of boost he is pushing, what setup, and that the setup has not changed. It is as close to a constant for me to base against as I can consistently get.

Pull up top, in this case, is that by 100 I am a car length+ ahead and the increase continues progressively. Before the scoops, it would be reversed.

So there is less variation in EVERY run by your buddy in his STI than there is performance gain from the scoops? As well, the scoops,and the scoops ALONE consistently provide 2 car lengths by 100 mph? Just want to make sure I understand your claims precisely.

[swamp2]

Originally Posted by Sticky

You rent a blimp hanger.

Or just use some common sense...

[Sticky]

Originally Posted by swamp2

You sure do an immense amount of defense of your decisions and this product if you have nothing to prove to me nor to others. I don't have anything to prove myself, I just like solid claims with solid evidence and dislike the opposite.



On the aforementioned piece of "evidence" and whether or not it is apples to apples I certainly have come to my own conclusion.



So there is less variation in EVERY run by your buddy in his STI than there is performance gain from the scoops? As well, the scoops,and the scoops ALONE consistently provide 2 car lengths by 100 mph? Just want to make sure I understand your claims precisely.

You post a lot for someone who doesn't care.

Glad you are capable of thinking for yourself.

There is less variation in my buddy's car than there is performance gain from the scoops? Could you explain this? I can't make sense of it.

What exactly are you trying to say? I have benchmarked my car vs. my bud with the STI every step of the way. His car serves as my own real world base to compare against.

The scoops ALONE, consistently, provided a positive difference vs. my friends STI. I'm not sure how much more precise I can be.

[kmac1980]

Originally Posted by Sticky

I don't know where you came up with that I was arguing BMW came up with the ultimate vehicle.

You are going to hang on to the fuel economy aspect as that is all you left. However, it depends where you are making this power and how. A tune can under less throttle load produce better mileage. A tune can lean the car out a bit, allowing it to burn better the fuel it is already using. There are many variables.

Regarding cats, depends which set you remove and when you test. You CAN pass with one set of cats.

Really, you would meet the stringent California ULEV ratings? So I guess BMW just threw in the 2nd set of Cats because they had some left over in the parts bin? Kind of a 2 for 1 sale?

Last time I checked Cats were pretty expensive, and im sure if BMW could meet all of the global emissions regulations with less (and be able to maintain lower costs) they would.

And right, I'm going to mod and tune the hell out of my car so I can drive it at 40mph in 6th gear under low throttle load and cruise around sipping fuel. Maybe you should post this revelation on a hypermiling board, they may trade in their Honda Insight for an M3 with a chip

[Radiation Joe]

Can I have some snake oil for my popcorn.

[swamp2]

Originally Posted by Sticky

You post a lot for someone who doesn't care.

I do care about potentially bogus performance mods, bogus claims and poor evidence in general. This is not a direct claim these things are happening or that you are doing so, but very many parts of this whole topic touch on these points.

Originally Posted by Sticky

There is less variation in my buddy's car than there is performance gain from the scoops? Could you explain this? I can't make sense of it.

What exactly are you trying to say? I have benchmarked my car vs. my bud with the STI every step of the way. His car serves as my own real world base to compare against.

The scoops ALONE, consistently, provided a positive difference vs. my friends STI. I'm not sure how much more precise I can be.

What I was saying is that you are measuring a variable (with and without scoops) against a constantly moving/variable target (the STI). So my question was simply can you be assured that in each instance of comparison that the STI is being driven and performing exactly identically? Since the only answer here is "no" you can't, you need to consider how much variation is in the STI's runs (say .2 seconds to 100, or +/- 2mph in the 1/4, whatever the numbers may be). Then if the scoops provide LESS benefit than this variation the test is simply NOT CAPABLE of determining the difference and benefit. Again to be clear, I am not saying this IS the case, just that it MAY be the case. Why not look at some of these numbers? Either way comparison against a variable target is not great evidence when the differences are small.

So many auto enthusiasts and modders simply ignore the fundamentals of valid experimentation.

-Apples to apples
-Statistical significance
-Accuracy of test method/equipment
-Factor isolation (i.e. one mod at a time)