JM

Hey!


Locally go to ADVANCE to get your ECU done they are now Powerchip dealer...

we flew Powerchip down to Richmond a few months ago to get ECU done

for a group of our cars they are amazing!

micropower99

Hey, yeah thats where I was planning to go. I was there yesterday talking to them about it.

Peabody

Wow I thought you were kidding until I got this far.. behold the difference of my friend's M3 dyno.. 41 days apart.. 36 degrees apart.. 59% humidity difference..

Peabody

You're right, silly Americans shouldn't try to use their inferior science. Then again, you're closer to a gibbon than an Einstein.

Glyn M Ruck

Ah! I've been insulted by professionals - blame the forefathers

Glyn M Ruck

And corrected - note!

JM

Who did you talk to ?

They are amazing people, all of them are great.

And I saw your picture on whdnl's facebook

I was the one he told him how to blackout his car and paint his grill.

kevink2

It sounds like you assumed no SAE CF was applied. Ok, then assume power produced is related to ambient temperature by that equation in J1349 used by all engine mfg's. It's Correction Factor is a function of the sq-rt of the absolute ambient temp ratio. So for a 70F vs a 74F test day (and related higher intake air temp), the correction factor for the power produced is:

[(460+70)/(460+74)]^.5 = .995 (ignoring the trivial .18 ME effect).

A 4 degree temp rise, F or C, does not cancel an independent 8% power gain.

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kevink2

With the shift issue, ony peak hp output will be usefull. How consistent were the 3 runs in peak hp? It appears an SAE correction factor was used ... see if you can find the value.

FastDonzi

there is a place in edison, called turbotrix. they are off rt.1 south.

micropower99

Yeah definitely. I talked to Alex but also met Curtis through his gf. Hopefully will get the ECU tune done in a couple weeks time and then either right before New Years or right after I will get another dyno done. Yeah Wes spoke of you a bit, his car def looks much better blacked out. Plus he blacked out just enough and didn't overdo it. I like it!

micropower99

I'll try to find out what SAE correction factor was used. The peak HP was 180 on all 3 runs. well on the first was 179, second 180 and third 181 I believe.

Glyn M Ruck

Correct - but adequate move in air density & IAT can certainly cause a 10% float along with many other factors. See my original post - All I was trying to do was to get these factors recognised in attempting to achieve a sane result. Reasonable guidance.

As people don't want to believe me they should search the net. There is some surprisingly good data on why dyno results are not repeatable & can be problematic in absolute terms. Cosworth also have some good data. Some of the best material is by those testing motorcycles. With bikes you have an easier situation generally because you can connect the GB output sprocket shaft direct to an eddy current brake or whatever. You don't have brake pads touching rotors & other things to throw you off track.

I'm going to clear out of micropower's thread now. We have some of the few dynos here at SASTECH that operate in a truly altitude compensated environment. You can wind the effective air pressure up & down in the dyno rooms - control IAT etc. Getting meaningful, repeatable results is still a nightmare irrespective of dyno resolution.

kevink2

With a mustang dyno, the pull can be longer to help line out some of the variables.

There is some argument whether IAT's are for instant IAT value, or general average value for a period of the day, since most have very slow response. But IAT is not a strong variable, as I showed.

My main point is there are "unintended consequences" when a forum guru like you makes a specific example like that. Your followers walk away thinking a 4 deg temp rise can wipe out an independent 8% power gain, and then overestimate the effect of intake temperature.

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I do consider you a true oil guru. I hope you will add links at the end of your ultimate-oil thread, to your many valuable oil explanations in various threads.

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JM

Yeah! His car turned out great, haha

Well go with Advance, they are amazing people and they have the best service I have ever found.

I told wes to get his eisenmann exhaust before the ecu tune

Peabody

That MAY well have been your intention, but you came off as complete douchebag that doesn't think a dyno can measure anything accurately accurate unless it costs a billion dollars and is operated by you and your friends, that Americans are too stupid to measure an elementary force or calculate variables, and that putting a car on a dyno before and after a mod is a ridiculous idea and a waste of time.

Glyn M Ruck

I acknowledge that wording such as "variation in IAT could lead to ----" would have been more appropriate. I think that most people would understand air density or barometric pressure effects.

I'm sure that you would agree that variation in IAT effects different engines differently with respect to output - it is not as simple as a JIS or SAE formula - even they do not correlate. On some set ups differences can be quite dramatic.

Suffice to say it is my experience that major engine builders involved in serious racing do not depend on dyno absolute power readings to predict the performance of an engine on a real world race track.

I do not retreat from my stance and I'm sure I have more time spent running dyno tests than most on this forum with all it's foibles. Certainly more hours than those that criticise or choose to call me a douchebag.

I do apologise for my sometimes blunt expression. I'm South African & that is our way.

Should you be interested in some even more blunt commentary from myself and timdf you might like to read these threads & those attached to them. Unfortunately poor micropower was involved in one of them which I had forgotten. Now I see why he thinks I troll for dyno threads. I don't.

https://mbworld.org/forums/c-class-w...ey-system.html

Here people are called "Idiots, Knuckleheads, Retards & worse!!

I also host a discussion on the AMS pulley - see link in thread

https://mbworld.org/forums/c-class-w...****+on+a+bull

imboom

I believe that's the reason why people have problems about your posts on this thread. Micropower isn't building a "serious" racing competition vehicle. He just wanted a baseline figure so he can see how much gains were from the ECU tune.

There is nothing wrong with seeing where your car stands from point A to B.

I've have had done many dyno runs on my EJ205 motor at sea level, identical temperature and humidity within a span of many months. All done because I was tuning my car and I've seen relative, consistent gains. Does this mean none of it is real? Nope. If I had multimillion dollar facility to "measure" my cars, I wouldn't have bought a C Class anyway.

Glyn M Ruck

Because he would be better off measuring a standing quarter mile or whatever distance of choice. Read the other threads - I'm not suggesting buggering around with a multi million dollar Dyno setup.

Peabody

Here's my problem with that.. not only do you have the same variables in the dyno lab affecting the outcome of this result (air density, temperature) but you introduce several human variables into the equation that make the results significantly less predictable.

Glyn M Ruck

That's your 4 Dollar haircut opinion to which you are entitled. Yes, wind direction etc can effect things but it gets all the dyno variables out of the way. - read the other threads - especially comments by Tim ex Cosworth that back up my general findings.

BTW - If I was talking about complex driving (rather than just flooring the car) such as driving the European urban cycle. Then I would let a computer drive the car on a very well sorted & calibrated dyno.

Peabody

There's several variables added besides wind resistance that will make clocking a quarter mile less predictable than a dyno. Tire heating, traction, lateral movement for course correction, reaction time, et al. So yeah, that's my four dollar haircut opinion, but at least it's better than yours.

Glyn M Ruck

How many times have you actually done it??? And how many times have you tried to stabalise a dyno. Sounds good in theory but in practice it's another story. If I had to choose between the opinions of Cosworth & you. Cosworth wins hands down. I also trust my own experience. Been down this road many times.

Your modesty is staggering.

Peabody

You can be "blunt" for being from a racist ****hole like South Africa, but it's pretty hypocritical to criticize me not not being modest enough. I'm not arguing that there are variables to consider in working with a dyno, just consider that your experience may have skewed your perspective outside what is considered normal and acceptable practice. A dynometer isn't made from voodoo magik, it uses newtonian physics from the 17th Century. It needs calibration like ANY engineering device, to include things as simple as a weight. You may also need to measure and compensate for variables to achieve a truly accurate result. Unfortunately, there's no way to calibrate a quarter mile run or compensate for most of the variables.

Peabody

Your argument is the equivalent of me arguing about the variables of contact resistance, electrical capacitance of air by mineral composition, and the effect of battery temperature on electron flow makes using a multimeter an inaccurate way determining the current flow of a 9 volt battery so you can achieve more predictable and practical results by using the "stick it to the tip of your tongue" test.