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

[Sticky]

Originally Posted by PencilGeek

Is that something like a wind speed and direction indicator?

Yes, but better.

[Sticky]

Originally Posted by kmac1980

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

Airbags are pretty expensive. BMW gives you far more than are required to meet the basic safety regulations. How come? Shouldn't they be saving money where they can? Why aluminum in the hood? Is 10 pounds really that big of a deal, couldn't they get away with something cheaper? Why even offer forged 19's? Cast wheels are cheaper, let the owner get forged wheels if he wants later. BMW builds a car to a higher standard, they take cost into account, but it is not the sole driving force. Can't believe I actually have to lay that out for you.

They give you the cats they do because having a set of cats upstream allows them to heat quicker. That way the car has cleaner emissions when started. Often, what people with a pre-cat delete do, is before an emissions test is run their car hard on the highway getting the cats hot. That way, they pass the test, the machine doesn't know how many cats the car has or where. The car is also built to exceed current standards, not squeak by them.

You obviously didn't get it. Try reading and comprehending this time. A tune CAN get better mpg. It depends on the application and use. Tunes usually lean the car out a bit. You don't have much experience, and that is ok, I don't mind tutoring you. Did you forget your original so called point that the car would somehow be compromised or require exotic materials to improve BMW's design? To simplify, you were wrong, I haven't had to sacrifice daily driveability. If anything, the case can be made the car is easier to drive everyday as there is more torque.

People who tune their cars for more performance usually drive around at 40 mph in 6th gear. That makes a lot of sense, great point.

[Sticky]

Originally Posted by PencilGeek

This is all just speculation...and not very good speculation IMO. The ALMS M3 had a cost-no-object racing motor and developed 485hp. So It's very doubtful that 500hp can be obtained from the 4.0L configuration, or that a rumored CSL had anywhere near 470hp.

To have 470 crank, the CSL would have had to be just under the 400 wheel range, or a gain of around ~46 wheel on a stock car. Completely feasible and attainable, from the factory or otherwise.

[Sticky]

Originally Posted by swamp2

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.



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)

I don't consider the target a variable, you do. His setup doesn't change, and from a roll launch doesn't mean anything. It is quite an accurate base IMO. We do enough pulls that we know. I don't make one run, he misses a shift or something, and proclaim the scoops as magical. Why wouldn't I want to know for myself?

It isn't scientific or measurable exactly on a graph to present, but it confirms the real world application for myself. The drag strip does as well.

[Gearhead999s]

Originally Posted by PencilGeek

This is all just speculation...and not very good speculation IMO. The ALMS M3 had a cost-no-object racing motor and developed 485hp. So It's very doubtful that 500hp can be obtained from the 4.0L configuration, or that a rumored CSL had anywhere near 470hp.

Dont not forget that the ALMS motors are a restricted engine to equalize the variation of cars & engines.The 4.0l race engine would pull a lot more power unrestricted.

[Sticky]

Originally Posted by Gearhead999s

Dont not forget that the ALMS motors are a restricted engine to equalize the variation of cars & engines.The 4.0l race engine would pull a lot more power unrestricted.

Not to mention they were making that power in 2001, and Porsche accused them of making far more

[Sticky]

Originally Posted by PencilGeek

I didn't know this. What are the restrictions? (Sorry to be off-topic...but I'm curious.)

Air restrictors.

When they did not homologate the V8, Porsche protested, they were forced to go to even larger air restrictors, before the throttle bodies I believe. This is when they decided it wasn't worth it anymore and hung up their M3 GTR racing shoes.

[Gearhead999s]

Originally Posted by PencilGeek

I didn't know this. What are the restrictions? (Sorry to be off-topic...but I'm curious.)

http://www.imsaracing.net/2007/aco/2007%20gt2.pdf

http://www.imsaracing.net/2008/alms/...201st%20ED.pdf

Page 243 is what you need for GT2

[kmac1980]

You clearly don't understand the basics of running a business. Airbags/safety stuff sells to a certain crowd. Weightsaving such as an aluminum hood, and forged wheels are what make fanboys such as yourself cream their pants... While they aim to produce a car you want to buy, they do it solely because they feel they can make a certain margin on you, not because it makes them feel good in their heart that you have dreams at night about your next trip to the drag strip.

There are few cars on the road today that are not a pure cost/price business case, such as the Bugatti Veyron, which is an engineering testbed/marketing tour de force. Trust me, your M3 is not in that category, it is a mass production car where every component is carefully considered in a cost/benefit (what BMW can sell the car for) analysis.

Originally Posted by Sticky

Airbags are pretty expensive. BMW gives you far more than are required to meet the basic safety regulations. How come? Shouldn't they be saving money where they can? Why aluminum in the hood? Is 10 pounds really that big of a deal, couldn't they get away with something cheaper? Why even offer forged 19's? Cast wheels are cheaper, let the owner get forged wheels if he wants later. BMW builds a car to a higher standard, they take cost into account, but it is not the sole driving force. Can't believe I actually have to lay that out for you.

They give you the cats they do because having a set of cats upstream allows them to heat quicker. That way the car has cleaner emissions when started. Often, what people with a pre-cat delete do, is before an emissions test is run their car hard on the highway getting the cats hot. That way, they pass the test, the machine doesn't know how many cats the car has or where. The car is also built to exceed current standards, not squeak by them.

You obviously didn't get it. Try reading and comprehending this time. A tune CAN get better mpg. It depends on the application and use. Tunes usually lean the car out a bit. You don't have much experience, and that is ok, I don't mind tutoring you. Did you forget your original so called point that the car would somehow be compromised or require exotic materials to improve BMW's design? To simplify, you were wrong, I haven't had to sacrifice daily drivability because. If anything, the case can be made the car is easier to drive everyday as there is more torque.

People who tune their cars for more performance usually drive around at 40 mph in 6th gear. That makes a lot of sense, great point.

[Sticky]

Originally Posted by kmac1980

You clearly don't understand the basics of running a business. Airbags/safety stuff sells to a certain crowd. Weightsaving such as an aluminum hood, and forged wheels are what make fanboys such as yourself cream their pants... While they aim to produce a car you want to buy, they do it solely because they feel they can make a certain margin on you, not because it makes them feel good in their heart that you have dreams at night about your next trip to the drag strip.

There are few cars on the road today that are not a pure cost/price business case, such as the Bugatti Veyron, which is an engineering testbed/marketing tour de force. Trust me, your M3 is not in that category, it is a mass production car where every component is carefully considered in a cost/benefit (what BMW can sell the car for) analysis.

Really? You clearly don't understand that BMW doesn't cut corners on the M3 simply for the bottom line. You missed the original point, AGAIN, which was just because they include something does not mean the car stops functioning or is neutered if you change it.

The M is an enthusiast car, they do cater to fanboys to an extent. They make FAR more money just churning out base 3 series. They would have made far more money simply plugging in a higher boost version of the N54. They didn't, that should tell you something.

Cars like the M3 are a matter of pride and prestige for the respective producers. They are not bottom line cars, although they do turn a profit. The numbers are nothing like the base 3 or 5 series.

I think you obviously do not understand the basics of performance cars, namely M cars.

Regardless, you are still wrong about what you wrote regarding the compromises of tuning an M car and that it requires expensive exotic materials to do so. Let me know when you are ready to admit it.

The Veyron was a car they could build as VW does not have a formula 1 program. They simply had the money to throw away to make a statement. They didn't need to make money on it, that is why the Golf exists.

[ChitownM3]

Originally Posted by Sticky

To have 470 crank, the CSL would have had to be just under the 400 wheel range, or a gain of around ~46 wheel on a stock car. Completely feasible and attainable, from the factory or otherwise.

Exactly. From what PGs car has made over stock with his mods, he's probably sitting right around 470 crank presently.

[kmax1980]

Originally Posted by Sticky

Really? You clearly don't understand that BMW doesn't cut corners on the M3 simply for the bottom line. You missed the original point, AGAIN, which was just because they include something does not mean the car stops functioning or is neutered if you change it.

The M is an enthusiast car, they do cater to fanboys to an extent. They make FAR more money just churning out base 3 series. They would have made far more money simply plugging in a higher boost version of the N54. They didn't, that should tell you something.

Cars like the M3 are a matter of pride and prestige for the respective producers. They are not bottom line cars, although they do turn a profit. The numbers are nothing like the base 3 or 5 series.

I think you obviously do not understand the basics of performance cars, namely M cars.

Regardless, you are still wrong about what you wrote regarding the compromises of tuning an M car and that it requires expensive exotic materials to do so. Let me know when you are ready to admit it.

The Veyron was a car they could build as VW does not have a formula 1 program. They simply had the money to throw away to make a statement. They didn't need to make money on it, that is why the Golf exists.

enough is enough, ive had my fun....OK you can make your M go stupidly muscle car fast with no compromises or expensive parts....I just didnt want anyone else to know that little secret:

[Sticky]

Originally Posted by kmax1980

enough is enough, ive had my fun....OK you can make your M go stupidly muscle car fast with no compromises or expensive parts....I just didnt want anyone else to know that little secret:

The secret isn't the bottle, it is actually Vin Diesel. When I put him in my trunk, I live my life a 1/4 mile at a time.

But hey, I applaud your OT effort.

[swamp2]

Originally Posted by Sticky

I don't consider the target a variable, you do. His setup doesn't change, and from a roll launch doesn't mean anything. It is quite an accurate base IMO. We do enough pulls that we know. I don't make one run, he misses a shift or something, and proclaim the scoops as magical. Why wouldn't I want to know for myself?

It isn't scientific or measurable exactly on a graph to present, but it confirms the real world application for myself. The drag strip does as well.

Thanks. In all honesty this is sounding like better evidence. Even from a roll there will be variables. Again that was the question. Your experience seems to indicate you know that the scoop differences are larger than the small run to run variations in the other cars runs. Reasonable, not perfect nor solidly conclusive but reasonable. But you know me, a small set of apples to apples runs with accurate timing of any sort is where the truth will be found.

[Sticky]

Originally Posted by swamp2

Thanks. In all honesty this is sounding like better evidence. Even from a roll there will be variables. Again that was the question. Your experience seems to indicate you know that the scoop differences are larger than the small run to run variations in the other cars runs. Reasonable, not perfect nor solidly conclusive but reasonable. But you know me, a small set of apples to apples runs with accurate timing of any sort is where the truth will be found.

Look, my feeling is the scoops are the best bang for your buck mod. You can show gains on a dyno with them, so they do give added air flow. However, they will never strut their stuff on a dyno, they need to be experienced at speed.

It is enough of a difference that you will feel it. It doesn't really matter to me as I don't make them, but what matters to me is that people don't throw stuff out there that isn't true.

I could technically get a VBOX and do runs with or without scoops, but it isn't worth the time or investment for myself. It would only be to prove "skeptics" wrong and investing more money than the mod costs itself is absolutely pointless.

[kmac1980]

Originally Posted by Sticky

The secret isn't the bottle, it is actually Vin Diesel. When I put him in my trunk, I live my life a 1/4 mile at a time.

But hey, I applaud your OT effort.

But Sticky, when is the bottle coming? All the mercedes 63 and E46guys are doing it! I haven't really looked, but haven't heard yet of any spraying their new m3 yet...

sorry for the thread jack

[Sticky]

Originally Posted by kmac1980

But Sticky, when is the bottle coming? All the mercedes 63 and E46guys are doing it! I haven't really looked, but haven't heard yet of any spraying their new m3 yet...

sorry for the thread jack

ASR is spraying their new M3. 100 shot, great gains for cheap.

[swamp2]

Originally Posted by Sticky

I could technically get a VBOX and do runs with or without scoops, but it isn't worth the time or investment for myself. It would only be to prove "skeptics" wrong and investing more money than the mod costs itself is absolutely pointless.

Good point. That is why on intake mods in particular it is the vendors responsibility to do this. JMO. As well I don't trust my butt dyno very much. We are way too easily fooled by noise and vibration.

[RPIpower]

Can you email me pics of the installation? Also, what type of dyno and were the scoops installed while on the dyno? Since the scoops are top mounted, the angle of the fan is very important. On our dyno, the cars sit tilting downward so the fans have to be placed lower pointing upward.

[alpine335i]

Wasn't the OP going to post pics of his car?

[ace996]

Originally Posted by Accord

I dyno'ed my M3 with my new RPI Air Scoops, high powered fans were used and 90mph wind was directed straight into the scoops and front grills.....with 90mph of wind the scoops are good for an extra 2hp at the wheels.

Thank you for posting independant dyno results, as there aren't many around.
Sorry that the results weren't what the vendor advertised.
Be good,
TomK

[dcstep]

You can't expect accurate results with the hood down. Even a 90 mph fan will not equate to the forced air cooling that happens on the road over 100 mph. (Taking the engine to the redline is equivalent to something over 155 mph on the road). The hotter air under the hood will cause the car to back off its advance and power will not be up to potential. Scoops are very hard devices to dyno accurately. Readings will tend to be pessimistic compared to actual results on the road.

Dave