Remember my fuel mixture got richer on my last dyno run and I really saw no peak hp or torque gain with the header/cats install, although there is a significant difference in the power delivery... well, chk this out..


"A lack of air-flow during dyno testing will almost always alter the fuel mixture in the rich direction as the radiator cannot exchange enough heat, resulting in the computer compensating by retarding timing and richening the fuel mixture to prevent the engine from overheating and detonating. In addition, the intake air sensor will read substantially higher temperatures than that seen on the road with proper airflow. This issue is particularly important to address when testing high output cars like the M5 or M3, and even more so on forced induction cars with intercoolers as the heat exchanger is not able to cool as efficiently because of the reduced air flow. The engine compartment is normally flushed with air driving down the road, particularly at speed, cooling the manifolds and other associated engine components. Cooler engine components and lower air intake temperatures will result in a leaner air/fuel mixture and ignition timing will be advanced, invariably resulting in greater power on the road than on the dyno. In simpler terms, accurate measurements can only be achieved when the dyno tests are conducted in a manner that simulates the car driving down the road, in as much as is possible. "

http://dinancars.com/whitepapersFile.asp?ID=9

http://members.roadfly.com/cbailey781/airfuel_ratio.jpg

Comsci,

The article also talks about how having a closed hood affects your output too. With your SMG and having to close the hood, caused more heat to build up. It later said that you never dyno with the hood closed.

Thanks Ced, some good reading and major props to Dinan with that huge 75 mph fan....I knew there was something wrong with those numbers on my runs but I don't sweat it tho, because they just numbers and I know my car still feels good evertime I mash on the gas. Keep those informative posts coming.. :cool

Comsci,

The article also talks about how having a closed hood affects your output too. With your SMG and having to close the hood, caused more heat to build up. It later said that you never dyno with the hood closed.

Ced, what happened to the other thread? I wonder why it got shut down...I thought it was getting very informative at the end. Oh well... :)

Keep the good stuff coming.

Ced, what happened to the other thread? I wonder why it got shut down...I thought it was getting very informative at the end. Oh well... :)

Keep the good stuff coming.
Some people are crazy.... :freak

Even the M5 got as rich as 9.5 on the dyno...

"The combination of the engine heating up and the air temperature sensor reading an artificially high value causes the engine management computer to go into the "engine savior mode". The mixture is richened to an astounding 9.5 to 1 air fuel ratio (see Figure 7 - violet line); whereas the correct mixture measured on the road was 12.2, shown in Figure 7 - blue line. The ignition timing is retarded from a peak value on the road of 27° (see Figure 8 - blue line) down to 15° (Figure 8 - violet line). It is truly amazing how intelligent a modern BMW is. If you were to go back just 15 years, these same conditions would likely result in engine damage!"

And here's the answer to those who think "powerchips" will help on the dyno numbers...

"I believe that the rather large horsepower gains that are being published by some, particularly with regard to "power chips", are the result of tuning the cars back to the stock mixture and ignition timing settings, essentially leaning-out the air/fuel mixture and advancing the timing to compensate for the rich mixture and retarded timing experienced on the dyno. It appears to me that this "increase" in power is then included in whatever gains were actually achieved (if any). In reality, these supposed gains are nothing more than a correction for the testing conditions, resulting in an exaggerated performance claim. In addition, many "power chips" create the perception of an increase in power/acceleration as the re-programming will often dramatically increase the speed of the throttle opening on the drive by wire cars, making the engine feel more powerful. "

Conclusion...

"If the engine is detonating or in the "savior mode" because of excessive temperatures, gains can not be measured. In fact if the car sits and heat soaks or cools for an excessive period of time between runs, enough variance can be created that the performance component enhanced car may show less power than the stock car, or even a very exaggerated gain.

By way of summary, following are some of the more significant factors that you should keep in mind when considering dyno testing in general terms, as well as what to look for in the facility itself.

1) Each dyno will produce different results (even with the same brand of dyno).

2) The octane rating of fuel varies in different parts of the country (you must have a controlled fuel supply).

3) Cold weather increases the gains and hot weather decreases them, even with temperature corrections.

4) Lack of oxygen from exhaust in a dyno room will cause a loss in power.

5) Slipping tires on the rollers will reduce the measured gains.

6) Inertia type dynos have a lighter load than the car will see on the road. This is especially true for cars with heavy drive trains because some of the power will get absorbed spinning the masses faster. The inertia correction programs employed in these types of dyno's are not completely accurate.

7) Fixed load dynos have a higher load than what the car sees on the road. This excessive load will result in a large mixture shift and the detonation sensor will be activated prematurely.

8) No dyno can accurately simulate wind resistance, the ram air effect into the airbox or cooling of the intake tract under the hood.

9) The size of the fan used during testing will change the power output.

10) Oil temperatures will affect output due to changes in friction.

11) The air intake temperature sensor will trigger adjustments to fuel mixture and ignition timing. "

Again, no offense Ced, do a search in FI. Most people do not like Steve Dinan's comments re: this issue. He has a very slanted/jaded point of view and his comments typically indicate that.

rE: the powerchips, most people fool around with the throttle portion resulting in a "feel" of increased HP. E.g., JC race shark injector does this. So this is not new news.

This comment makes no sense to me, perhaps others can enlighten me.

are the result of tuning the cars back to the stock mixture and ignition timing settings

If powerchips is tuning the car back to stock mixture and stock timing settings, how in the world is it leaning out the mixture? He just said it takes the car back to stock mixture and stock timing. Then, how can you lean out the mixture and advance timing to compensate for the rich mixture and retarded timing on the dyno. That makes no sense to me if the powerchips is using stock mixture and stock timing as he says.

Thus, how does he explain when you can take a stock car, dyno it -- get one reading, take the exact same stock car, on the exact same day (reducing a lot of different variables), dyno it on the same exact dyno, with the exact same fan, with the exact same room, and powerchips has increased values? What exactly changed? The dyno is the same, the car is the same, the relative manner in which both cars dynoed are the same -- to me, that would disprove his comments.

Someone correct me if I am wrong here. If he is claiming the "dyno" is what is causing the increased powerchip gain, which this is the way I read it, that can't be right because the conditions I just mentioned above are the same for stock software vs. powerchip software. Moreover, if powerchips using stock fuel ratio's and timing -- then how is it any different from the stock software? Why would it yield different numbers on the same dyno on the same day?

just curious to see what others think. Sean, what do you think? You are a little bit more versed in this area than me.

Ced -- are you going to play devil's advocate here ;)

I'll check into it. I'm relying on expert advice from a BMW Tuner, recognized by BMW. Knowledge is power, but we need concrete information from experts, not from someone that haven't had any hands on experience, or do not know the details. I would say that if someone would come it up with a white paper from "Powerchips" then I could be convinced. Someone like Dinan that has been in business for over 25 years, has more knowledge about BMW tuning, than most, and I just can't argue with them, but I would love to see some concrete evidence to back your arguement or your questions which indicate your lack of knowledge on the subject. Feed me some info. :D

Again, no offense Ced, do a search in FI. Most people do not like Steve Dinan's comments re: this issue. He has a very slanted/jaded point of view and his comments typically indicate that.

rE: the powerchips, most people fool around with the throttle portion resulting in a "feel" of increased HP. E.g., JC race shark injector does this. So this is not new news.

This comment makes no sense to me, perhaps others can enlighten me.



If powerchips is tuning the car back to stock mixture and stock timing settings, how in the world is it leaning out the mixture? He just said it takes the car back to stock mixture and stock timing. Then, how can you lean out the mixture and advance timing to compensate for the rich mixture and retarded timing on the dyno. That makes no sense to me if the powerchips is using stock mixture and stock timing as he says.

Thus, how does he explain when you can take a stock car, dyno it -- get one reading, take the exact same stock car, on the exact same day (reducing a lot of different variables), dyno it on the same exact dyno, with the exact same fan, with the exact same room, and powerchips has increased values? What exactly changed? The dyno is the same, the car is the same, the relative manner in which both cars dynoed are the same -- to me, that would disprove his comments.

Someone correct me if I am wrong here. If he is claiming the "dyno" is what is causing the increased powerchip gain, which this is the way I read it, that can't be right because the conditions I just mentioned above are the same for stock software vs. powerchip software. Moreover, if powerchips using stock fuel ratio's and timing -- then how is it any different from the stock software? Why would it yield different numbers on the same dyno on the same day?

just curious to see what others think. Sean, what do you think? You are a little bit more versed in this area than me.

Ced -- are you going to play devil's advocate here ;)

Hey, you are the one wanting information, you need to let your fingers do the walking :stickoutt

http://forums.bimmerforums.com/forum/showpost.php?p=3354291&postcount=12

If you understand this, then you'll understand that say you know what your LTFT is (remember I mentioned LTFT and STFT are kind of impt. in that other thread), say it is 5%, that means at WOT, that static maps for your dinan software are being enriched by that amount. Closed loop tries to maintain stoich.

If tuning is properly done, the DME will not adapt/lean the mixture out of anythiing significantly. If it does, then the company probably tuned closed loop very rich! Too rich in fact. From what I understand, whatever adaptations made at closed loop, at open loop -- the same adaptations would be applied.

Thus, the way I read these comments were, at closed loop -- powerchips have the same afr's and timing as stock software. Thus, why under open loop, would they perform differently than stock software. Did I explain it more clearly now?

I could be completely wrong as well, I'll be the first to admit here. You said your source is a well-respected BMW tuner. From what I know, there are only three individuals that would qualify: Dinan, Conforti, and Nick. Is this one of your sources?

Conforti and dinan work on the same principle I believe, you can change closed loop -- but, 14.7:1 is used b/c of emissions purposes IIRC. Changing that, probably makes you fail emissions and is illegal. Hence, aftermarket companies, IMO, probably fool around with closed loop ... thus, they can make more power than say Dinan or JC ... So, that's why I belive you "could" make more power with other tuners b/c they are willing to do stuff than say dinan does.

I do not think it's mere illusion though as it seems your well-respected bmw tuner indicates ... you "can" make more power, if you are willing to throw the lambda stoich out the window. Again, if I am wrong, please correct me. I'd like to know as well. :)

Ok, I'll look...

I looked. I still need a white paper, because that is not at detailed level such as testing, dynoing, etc... like the whitepaper Dinan put together... "Whitepaper" means an expert paper.

About throwing the Lambda out the window, and making power - is for dyno reference only... thus you can make the dyno read higher, but that's not real life. The lambda numbers are different on the street thus more power is made.

Do you really care to put your engine under stress on the dyno just to show better numbers just for advertising? The engine is obviously heating up based on how rich the A/F ratios show. I care not to do that, but whatever cranks your tractor :D


Hey, you are the one wanting information, you need to let your fingers do the walking :stickoutt

http://forums.bimmerforums.com/forum/showpost.php?p=3354291&postcount=12

If you understand this, then you'll understand that say you know what your LTFT is (remember I mentioned LTFT and STFT are kind of impt. in that other thread), say it is 5%, that means at WOT, that static maps for your dinan software are being enriched by that amount. Closed loop tries to maintain stoich.

If tuning is properly done, the DME will not adapt/lean the mixture out of anythiing significantly. If it does, then the company probably tuned closed loop very rich! Too rich in fact. From what I understand, whatever adaptations made at closed loop, at open loop -- the same adaptations would be applied.

Thus, the way I read these comments were, at closed loop -- powerchips have the same afr's and timing as stock software. Thus, why under open loop, would they perform differently than stock software. Did I explain it more clearly now?

I could be completely wrong as well, I'll be the first to admit here. You said your source is a well-respected BMW tuner. From what I know, there are only three individuals that would qualify: Dinan, Conforti, and Nick. Is this one of your sources?

Conforti and dinan work on the same principle I believe, you can change closed loop -- but, 14.7:1 is used b/c of emissions purposes IIRC. Changing that, probably makes you fail emissions and is illegal. Hence, aftermarket companies, IMO, probably fool around with closed loop ... thus, they can make more power than say Dinan or JC ... So, that's why I belive you "could" make more power with other tuners b/c they are willing to do stuff than say dinan does.

I do not think it's mere illusion though as it seems your well-respected bmw tuner indicates ... you "can" make more power, if you are willing to throw the lambda stoich out the window. Again, if I am wrong, please correct me. I'd like to know as well. :)

And here's the answer to those who think "powerchips" will help on the dyno numbers...

"I believe that the rather large horsepower gains that are being published by some, particularly with regard to "power chips", are the result of tuning the cars back to the stock mixture and ignition timing settings, essentially leaning-out the air/fuel mixture and advancing the timing to compensate for the rich mixture and retarded timing experienced on the dyno. It appears to me that this "increase" in power is then included in whatever gains were actually achieved (if any). In reality, these supposed gains are nothing more than a correction for the testing conditions, resulting in an exaggerated performance claim. In addition, many "power chips" create the perception of an increase in power/acceleration as the re-programming will often dramatically increase the speed of the throttle opening on the drive by wire cars, making the engine feel more powerful. "

So...in a nutshell, above is saying that cars will experience lose on power on dyno and software upgrade ("powerchip" in this case) does nothing more than bringing the car back to the state of what the car could have done on the road. If that is true, I would think Dinan will have the hardest time selling their own software. If software hardly does anything, why would anyone buy more expensive software from Dinan? :D

James, your understanding of fuel map, STFT, LTFT, and adoptation is the same as mine. As for me, dyno charts from before and after software is convincing enough. Even if Dinan himself came here and disapprove the dyno result, it would not matter much unless he can back up his claim with dynos. Dinan is in BMW tuning business for many reasons and I am sure the biggest reason is to make money. So unless I see some concrete evidence of how some of other software upgrades do not do anything, I would have to think *discrediting other softwares* is more of business practice than anything else.

So...in a nutshell, above is saying that cars will experience lose on power on dyno and software upgrade ("powerchip" in this case) does nothing more than bringing the car back to the state of what the car could have done on the road. If that is true, I would think Dinan will have the hardest time selling their own software. If software hardly does anything, why would anyone buy more expensive software from Dinan? :D

James, your understanding of fuel map, STFT, LTFT, and adoptation is the same as mine. As for me, dyno charts from before and after software is convincing enough. Even if Dinan himself came here and disapprove the dyno result, it would not matter much unless he can back up his claim with dynos. Dinan is in BMW tuning business for many reasons and I am sure the biggest reason is to make money. So unless I see some concrete evidence of how some of other software upgrades do not do anything, I would have to think *discrediting other softwares* is more of business practice than anything else.

Dinan can dyno the cars to read higher numbers without software tricks, as opposed to any dyno shop or software tricks... There's no need to trick the safety features built in the these engines that can be fragile due to heat...Everyone know the e46 M3 history on heat concerns and bearings...

Tricking the SW on the dyno just to read bigger numbers, because your dyno shop can't actually simulate a real world scenario, is not something I'm interested in, bottomline. I want to know about the driveability in the real world.

I don't dbelieve Dinan is discrediting other business, but they are putting out the facts, as opposed to some people who are opposed to Dinan because of the entry price of owning his products.

Dinan can dyno the cars to read higher numbers without software tricks, as opposed to any dyno shop or software tricks... There's no need to trick the safety features built in the these engines that can be fragile due to heat...Everyone know the e46 M3 history on heat concerns and bearings...

Tricking the SW on the dyno just to read bigger numbers, because your dyno shop can't actually simulate a real world scenario, is not something I'm interested in, bottomline. I want to know about the driveability in the real world.

I don't dbelieve Dinan is discrediting other business, but they are putting out the facts, as opposed to some people who are opposed to Dinan because of the entry price of owning his products.

It doesn't make sense to assume that other software upgrades are tricks and gimmicks to produce more power when Dinan software is nothing more than one of those softwares. :)

Dinan is putting out their knowledge and understanding of the software tuning. Whether one believes them to be facts or not is totally up to him/her.

It doesn't make sense to assume that other software upgrades are tricks and gimmicks to produce more power when Dinan software is nothing more than one of those softwares. :)

Dinan is putting out their knowledge and understanding of the software tuning. Whether one believes them to be facts or not is totally up to him/her.

Agreed. :redspot

All this talk has got my head dizzy! I'm just gonna go for a drive and Enjoy my ??? HP... :rofl

All this talk has got my head dizzy! I'm just gonna go for a drive and Enjoy my ??? HP... :rofl

Seeeeee...... :D

Isn't that spelled with a 'C'? I don't know spanish though... :thumbup:

Isn't that spelled with a 'C'? I don't know spanish though... :thumbup:

see, like, "you didn't know", like basically being in agreement... :redspot

Wow! :eek Isn't that like a pun or something... No. It's a ________ I can't think of it. When something has two meanings...

Wow! :eek Isn't that like a pun or something... No. It's a ________ I can't think of it. When something has two meanings...

I forgot what you call that, I'm going to have to pull my english handbook out tomorrow at work... I have a minor in English too :) I guess it has been to long to remember.

:lol3 How funny. I was thinking Similie, but that's not it... We suck!

Why did your "Dynos Lie" thread get towed thru the mud and then get closed? :dunno

:lol3 How funny. I was thinking Similie, but that's not it... We suck!

Why did your "Dynos Lie" thread get towed thru the mud and then get closed? :dunno

Because a lot of bashing posts, personal attacks, got posted late in the thread; thus, it was cleaned up and closed.

Hmmm. Silly. All this over cars. Although, I've been known to be an argument starter, so, I'm just used to all that stuff.... :dunno

I STILL SAY DINAN ROCKS! :buttrock

Interesting article on how to improve your performance...

"Push the Accelerater Pedal Down Further"

Somewhat related to the "powerchip" software programming...

http://www.spswebpage.com/tech/index.php?articleID=free_performance