E39 M5 runs 11.9@121 in the 1/4 - Page 16

drallen · 22nd December 2007, 03:20

Don't you just love the navel-gazing analysis of the S3 motor by people who don't have a fu*king clue as to what makes it tick? Here's a big clue folks - the S3 doesn't have MAFs.

[/b][/quote]

This is new to me...? then what type of system does the S3 use for its A/F ratio?

Mark

THRILOS5 · 22nd December 2007, 04:35

Quote:

Originally Posted by drallen

Don't you just love the navel-gazing analysis of the S3 motor by people who don't have a fu*king clue as to what makes it tick? Here's a big clue folks - the S3 doesn't have MAFs.

[/b]

This is new to me...? then what type of system does the S3 use for its A/F ratio?

it uses a MAP sensor(manifold absolute sensor) or speed density system

EM5PWR · 22nd December 2007, 05:27

I think a M5 board boxing match would be a novel idea...

Kelster · 22nd December 2007, 05:46

Quote:

Originally Posted by drallen

This is new to me...? then what type of system does the S3 use for its A/F ratio?
Mark

I'm not sure how the A/F ratio is controlled on the S3, but I do know that it doesn't use the MAFs 'cause they've been removed. The Dinan "Supercharger Kit Installation Directions for Installation on an S2-M5 Special 'Outside Shops' Version," is silent on this subject. The manual is very much nuts & bolts in nature and has little technical or scientific information. I do know that all the air intake hardware is removed beginning on page 4, item 12 which states:

"Remove the air filters and intake ducts/hoses all the way to the intake plenum. Remove the carbon fiber intake tubes on S2 cars these will not be reused."

And I specifically remember selling the MAFs and other related surplus pieces to Board Member H Bomb (Harrison). A quirk of the S3 installation is that the OBC can no longer calculate mpg because it no longer receives the needed signal from the missing MAFs for the computation. But curiously the OBC still somehow manages to generate a bogus mpg calculation, showing the S3 obtaining over 24 mpg! My initial reaction was "Wow, all this horsepower and economy too!" Not believing the forgoing mpg figure for more than a nano second I did a manual mpg calculation which quickly disabused me of that mistaken notion.

How does the S3 manage air-fuel ratio? Probably through the wide band O₂sensor would be my guess.

Ray

FAST 5 · 22nd December 2007, 06:07

Quote:

Originally Posted by Kelster

I'm not sure how the A/F ratio is controlled on the S3, but I do know that it doesn't use the MAFs 'cause they've been removed. The Dinan "Supercharger Kit Installation Directions for Installation on an S2-M5 Special 'Outside Shops' Version," is silent on this subject. The manual is very much nuts & bolts in nature and has little technical or scientific information. I do know that all the air intake hardware is removed beginning on page 4, item 12 which states:

"Remove the air filters and intake ducts/hoses all the way to the intake plenum. Remove the carbon fiber intake tubes on S2 cars these will not be reused."

And I specifically remember selling the MAFs and other related surplus pieces to Board Member H Bomb (Harrison). A quirk of the S3 installation is that the OBC can no longer calculate mpg because it no longer receives the needed signal from the missing MAFs for the computation. But curiously the OBC still somehow manages to generate a bogus mpg calculation, showing the S3 obtaining over 24 mpg! My initial reaction was "Wow, all this horsepower and economy too!" Not believing the forgoing mpg figure for more than a nano second I did a manual mpg calculation which quickly disabused me of that mistaken notion.

How does the S3 manage air-fuel ratio? Probably through the wide band O₂sensor would be my guess.

Ray

I checked my car tonight, and sure enough zero/ no MAFS........ something I never thought about until I saw what Ray had mentioned in his previous post.
Guys.......... why is this now a pissing contest, or.........
whos cock is bigger than your cock contest ???
COME ONE NOW .................................... PLEASE !!!!!

rneedham1979 · 22nd December 2007, 07:01

The S3 has to use a MAP sensor. i am not sure if it has one factory or not but... if it does you could use the map to make the tune off of it alone by using tuning the timing and fuel tables to the MAP. you can also use a default VE table. A map can be used as long long as the tune request 0 voltage from the MAF. Another way is to use a Throttle positioning Sensor by creating the tune off of the throttle position. Not the best way or safest way to do it but it can be done. The only downside to using a MAP is that the ecu cannot make the best correction for altitude, barometric pressure or enviormentals in short... but it will work (obviously) great. The best way to do it would be to use a MAF, the problem when using a MAF on a supercharger or forced induction is if you have the MAF after the blower or turbo you will most likely get a symptom called MAF noise, this is where there is turbulence or just to many GPS (grams per second or air) passing by the MAF) This is commonly referred to a push through set up, the best way to run is a MAF on FI is with a pull through set up, this is when you have the MAF before the blower or turbo. This would allow the MAF to make all the needed corrections for the enviormentals and will have less turbulance than the MAF being after the blower. Like i said this is the most desirable way to run because this will allow the DME or ECU to make the best corrections and it will allow allow you to still drive the car if the map fails or if the MAP fails. Currently if you are running speed density or MAP based tune and it fails you could be screwed or if you are running a MAF only based tune you could run into the same thing. I am not 100% sure but the M5 must have a MAP or something that is measuring manifold pressure. I suspect dinan just removed the MAF, made the DME command 0 voltage and used the MAP sensor for the tune. As for how the DME makes air fuel adjustments.... The tune has a commanded lamda (air fuel). For conversation we will say at 5000 rpm the DME commands 12.2 air fuel. The DME will try to get it to that number the best it can. Air fuels are controlled by the DME which gets all its info from sensor and most importantly the O2 senor which should be a narrow band in the M5. If the DME commands 12.2 but it only sees 12.5 at 4800 rpm the DME will tell the injectors to speed up the pulse because it requires more fuel. This is why i made the comment so on my prior post about fuel injectors. if your injectors are at 95-100% duty cycle and the DME request more the DME will increase the pulse of the injector and you will most likely go lean because you are out flowing the injectors(running out of fuel) which could be very bad. If the injectors dinan chose are operating at 70-85% duty cycle you will be good up to around 90-100 duty cycle. for conversation purposes this will look like this, the air fuel is 13.0's (lean) at 5000 rpm and the tune request a commanded air fuels of 12.5. The DME will increase the pulse to try to get the commanded air fuels. i hope this isn't confusing but that is how it all works in a nutshell. i am surprised he decided to remove the MAF all together. Are you sure there isn't a MAF just after the filter? Just one ore thing, most vehicle run the same or similar computer controlled set up for engine management. With this being said the S62 isn't to much different that say a VW, audi or even a ford. Yes I said it a ford. The big thing about tuning these DME's is only a handful of people have the software and it is very expensive and in most case someone need to reverse engineer the software to make a program in which you can create and write a tune. That is what makes the engine management in these cars special. For example tonight i was tinkering with a buddies Pontiac GTO. We had to remove the tranny to install a quick bleeder valve for the clutch. the tranny had to come out. etc This car is a daily driver and running 10's. it is a twin turbo. This car from the factory comes with a MAP and a MAF. The car has made 680 whp on low boost and is capable of over 750 whp with race gas and high boost. Guess how the car is tuned? It has the MAF commanding 0 voltage and MAP is sending manifold pressure to the ECU. Sounds kind of similar doesn't it..... I really do love S3 and I really hope when you decide to turn the boost up you look at what injectors you are running and make 100% sure the DME can meet the commanded fuel it needs too not go lean. I hope this info helps someone. Once again good luck with the boost and breaking into the low 11's

Ryan

Quote:

Originally Posted by Kelster

I'm not sure how the A/F ratio is controlled on the S3, but I do know that it doesn't use the MAFs 'cause they've been removed. The Dinan "Supercharger Kit Installation Directions for Installation on an S2-M5 Special 'Outside Shops' Version," is silent on this subject. The manual is very much nuts & bolts in nature and has little technical or scientific information. I do know that all the air intake hardware is removed beginning on page 4, item 12 which states:

"Remove the air filters and intake ducts/hoses all the way to the intake plenum. Remove the carbon fiber intake tubes on S2 cars these will not be reused."

And I specifically remember selling the MAFs and other related surplus pieces to Board Member H Bomb (Harrison). A quirk of the S3 installation is that the OBC can no longer calculate mpg because it no longer receives the needed signal from the missing MAFs for the computation. But curiously the OBC still somehow manages to generate a bogus mpg calculation, showing the S3 obtaining over 24 mpg! My initial reaction was "Wow, all this horsepower and economy too!" Not believing the forgoing mpg figure for more than a nano second I did a manual mpg calculation which quickly disabused me of that mistaken notion.

How does the S3 manage air-fuel ratio? Probably through the wide band O₂sensor would be my guess.

Ray

rneedham1979 · 22nd December 2007, 07:03

Oh one lat thing. have you traced the inter-cooler plumbing to se if there is a push through MAF set up? Or a MAP sensor somewhere on the inter-cooler piping?

Lscman · 22nd December 2007, 15:15

MAP can theoretically provide better throttle response and performance than MAF, if it's calibration is optimal. A speed density engine control strategy is less reactive, so throttle changes lead to immediate adjustments of individual injector control signals. This results in better fuel mgmt timing. The MAF systems rely upon changes in actual intake air flow that occur AFTER any throttle pedal adjustment is made. This makes MAF very flexible, adapting to big changes in air flow from user-installed engine mods. Accurate mass air flow meter(s) generally add some flow restriction to the induction system. When larger, less restrictive meters are utilized, their accuracy generally suffers as air flow velocity drops.

The problem with "fixed" MAP in general is it's not very flexible or tolerant of modifications. By fixed, I mean EPA legal with no user interface for recalibration. Big changes in air flow from head work or forced induction hardware could quckly go beyond the operating bandwidth of the algorithms, unless engine mgmt software had some sort of user calibration adjustment feature or the tuner/mfr offered pre-calibrated chips/software for specific "already tested" mods. The speed density strategy only deduces air flow because it does not have a physical air flow meter. Tables and algorithms try to guesstimate/extrapolate air flow based upon a known engine setup. This means if you make certain modifications after the engine is built without altering engine mgmt software, the A/F ratio might be impacted. This could cause problems...especially in forced induction scenario.

Kelster · 23rd December 2007, 15:22

Let's get a grip. I've never made any false accusations against you. And if you believe I did, I ask you to identify the basis for this statement. If you can back this up I'll apologize.

My issue with you boils down to this. Without having any real hard data on track elevations at Atco, you jump into this thread on 12/15 and in response to the question "Is Atco a fast track?" you flatly state

Quote:

Originally Posted by lscman

...It's only 33 feet above sea level at the traps and 90 feet above sea level at the start.

This would make the elevation of the starting line nearly 60' above the finish line - the equivalent of a 5-story building! And then it snowballs. Another Board Member, accepting your elevation data as gospel, then digs out a trigonometry text and calculates that this means the track has a downhill slope of 2.5 degrees!

Quote:

Originally Posted by T Bone

I just calculated that ATCO has a 2.5 degree grade.....

Now I've been racing at Atco for over 20 years and intuitively know that I haven't been starting my races from atop a 5-story building or running down a 2.5% grade. I believe we can resolve this once and for all by having someone with a GPS take elevation readings at the starting and finish lines.

Quote:

Originally Posted by Lscman

Listen Kelster,

You are unfairly characterizing me in a negative way and making totally false accusations against me.

Yes I've disagreed with you but never knowingly made 'totally false accusations' against you.

Quote:

I did not attack anyone here in a personal fashion & neither should you. I absolutely do not have a preconceived agenda. Initial information I found suggested the track was not flat & I posted it, including various track elevations that I found and other's did too that vary between 95' and 33'. I tried to search and solicit more technical information about the track and this was challenging. Spotty & sometimes divergent (contrary) information was collected from many sources.

A caveat qualifying your first comment on the Atco elevation data would have gone a long way to have put this in a proper perspective. As it was, it instantly cast aspersions on the ETs achieved by those of us running that day.

In a 12/17/07 posts T Bone gave us these links: http://www.dodgetalk.com/forums/show...0&page=1&pp=20
and
http://www.e90post.com/forums/showthread.php?t=102134

The former takes us to Information on Atco elevations posted on the "Dodge Talk Community Forum" in a 12/03/2006 post by 'helio-pilot' where he stated

Quote:

Atco Raceway elevation data:

Staging lights = 95.1 ft
1/8th mile 95.1 ft
1/4 mile 95.0 ft

I don't think I need to list the grade on that one.

Later on in the thread helio-pilot mentions this data was obtained by satellite but unfortunately doesn't supply the source for this information. Too bad you didn't (a) find this link or (b) choose to ignore it in favor of your thesis that Atco has a nearly 60' differential between the start and finish lines. In that the post was from 12/03/2006, you should have been able to find it on Google.

The second link is to E90post.com where member Tturbobullet in response to an inquiry from T Bone(?) states

Quote:

Its a flat track, i dont believe there is an elevation change from the trees to the trap. The elevation is approx 94ft ASL if i remember correctly. I grew up literally 200 yards from the place you would think I would know all this stuff

There are 4 other reply posts in the thread which all agree that Atco is essentially a flat track with a minimal elevation differences at the start/finish lines. In your 12/16/07 post you continue to state

Quote:

Originally Posted by lscman

...I'm simply noting that ATCO is not level...

And again on 12/18/2007 you yet again make more negative remarks about Atco's elevation

Quote:

Originally Posted by lscman

6) The ATCO track stage area is clearly at higher elevation near Jackson Rd, across from a housing plan. The ATCO trap section (finish line) slopes downward, ending in a low-lying swampish runoff water collection area that eventually turns south to drain along Austins Causeway Road. This road name is not coincidental. The track is sloped downhill according to topo maps and sporatic info I've seen which is likely why it produces impressive results.

In light of other data which by now has come to light, I believe it is irresponsible of you to continue harping that Atco is downhill.

Quote:

This is not grounds for a personal attack.

Asked and answered. Show me.

Quote:

Your quotations of my posts are cleverly flopped out-of-order, so progress looks encumbered (duh).

Huh? Please explain.

Quote:

The fast track inquiries were posted first, followed by slope, prep, NHRA and site grading discoveries. In an ongoing effort to denigrate me, you "blissfully" ignore my prior reply to CSBM5 about track slope:

I'm not sure what you are trying to get at.

Quote:

...AMAZINGLY, you selectively dismiss information that supports a level track scenario while attacking me for considering & acknowleging it.

Say what? What pray tell am I selectively dismissing? I have been saying Atco is flat right from the beginning. Get your facts straight.

Quote:

You really need to do a self-assessment before taking such a stance because hypocricy comes to mind. I am not going to visit ATCO to satisfy you.

WTF is this all about? No, don't visit Atco; you might actually see something

Quote:

NHRA track approval is impressive & indeed notable, but it may or may not be significant wrt level track. Do you know if NRHA tracks have a slope/level specification? After hours of searching, I am unable to effectively filter through the reams of NHRA safety guidelines to find ANYTHING relating to track construction/design wrt max slope specifications or anything remotely similar. How long have you spent searching for that? I do not know what technical guidelines the NHRA uses with respect to approving a track layout, but likely exist. These rules may include track surface type, runoff distance, timer accuracy and levelness, but this is purely a guess. All I can find is millions of rules relating to track safety and classes. Perhaps a NHRA rulebook needs to be purchased. Track design parameters are NOT contained in any pro or amateur racing rulebook I've owned, so this info may be difficult to get.

Just because you haven't been able to find the NHRA dragstrip construction standard isn't really relevant at this point. The National Hot Rod Association ("NHRA") is the preeminent drag racing sanctioning body in the United States. In addition to establishing safety standards they establish rules and keep track of the ET and mph records for each class. Wouldn't it be reasonable to infer that for in order for the NHRA to maintain class records set at "NHRA Approved" 1/4 mile race tracks that (a) the tracks must be 1/4 mile in length and (b) the tracks must be "flat" (to a certain standard)?

Quote:

If you have ANYTHING to provide aside from personal attacks and the acronym "NHRA", why not share it? Technical information about superchharged M5's, ATCO or drag racing is appreciated and would seem to be on-topic. Attacking me is not on-topic.

Asked and answered. A post from you acknowledging that based on new information it now appears that Atco is indeed flat. Yes I know that you finally did concede that it 'might' be flat, but that was in the middle of another post and some may have missed the point

Lscman · 23rd December 2007, 16:38

Holy cow Kelster...settle down, please. Unfortunately I have no therapeudic skills.

As I explained several times when you got in my face before....the data I posted was collected from various websites & my initial opinion was indeed formulated from it. Other's stumbled upon this SAME info, as they searched in a similar way. Unconfirmed web info found through searching is subject to error and it's often conflicting. It is not particularly reliable, as I noted a half dozen times. This info is generally presented and then sanitized (accepted or thrown out) through spirited discussion. You totally lose it when opinion diverges from your position.

The hypothetical suggestion that ATCO is fast and therefore may not be flat clearly set you off. I really was not looking to trigger that behavior. I was only hoping to solicit additional data from other parties to proceed with spirited thought and analysis. You need to remain composed and control your behavior when contrary opinion or conflicting info is being offered.

Nobody found a site survey or NHRA requirements relating to track slope, so topo info, first-hand comments about landscaping/grading and race track web site info is nearly all we have to go on. After reviewing all the web info and throwing out certain spurious data collected on the net that is seemingly flawed, the first 1/4 mile of the track might be close to flat.

It's seemingly your position that all drag strips (whether fast or slow) are flat and anyone questioning that assumption shall be ridiculed and scorned. Christopher Columbus would surely understand. Unless you have some agenda, elevation data collected from various sources should not be categorized as "negative remarks", as you just stated.

Data was never uncovered showing that ATCO track surface was indeed flat (or sloped). We can only hypothesize, surmise or deduce that NRHA approval mandates a max slope spec. Confirmation would seem to require some NHRA track specs, ATCO site survey specs or some sort of municipal civil site survey info. We ultimately collected some info for landscaping, site fill & topo that showed ATCO indeed "could" be flat in the first 1/4 mi. The adjacent creek flow still disturbs me a bit, but a flat track appears possible if it's built-up in the trap area.

-------------------------------

I realize my intense style of discussion brings out the worst in certain unstable folks. While many seem to appeciate spiritied discussion because it generally uncovers things, a very small handful of folks become childish or even psycho.

I post my opinion without attacking other folk's posts or denigrating them. Opinion and data posted in threads is always subject to misinterpretation & error. Bashing behaviors directed toward other members only serve to degrade the quality of the thread. I largely limit my posts to technical opinion and defense of my character, whenever necessary.

I agree you need to get a grip....hopefully before Christmas.