I'm kinda suprised nobody looked at gear ratios in conjunction with the dyno, as the evo 8 and 9 and MR all have slighty different ratios. Elevation might also affect the density of air also. These might effect numbers slightly.

In all honesty, for the readers on here, I think dynos are for bragging rights. If you want a true test of your car, take the closest standard out there and take it to the 1/4 tracks. It'll test all real world numbers and gear ratios. Log your wb02 or whatever and tune out there.

I gained between 2-3 mph trap after every tune at the tracks on my 4 runs (on avg) with a upgraded turbo, dsmlink, and wb02. But it also got colder also (from 90degrees to 72degrees intake temp). Anyhow, all I have to say is this: Dynos are for talking the talk. Timeslips are for walking the walk.


And for those of you that think a engineering degree doesn't mean anything, try getting one, and maybe you'll respect people with them more. Or ask your boss, unless he's a business major, those guys don't count

 

Ok your right Shiv. Now how is Road tuning unaccurate like you said when you started this whole thread? Road tuning has to be adjusted to be accurate how? This is the only question I will ask for now on. I will also not add anything to any comments. Please school me in this matter. This is the topic. Thanks

 

+1 just to try to keep it on a scope of technical questions and answers from the 2 parties involed and no followers like the vishnuites and um dynoites?

 

Shiv I talked to you earlier today on the phone when exactly are you comeing down here so I can get ready?

 

The shortcomings of road tuning (inability to control variables, inability to accurately quantify the results of each mapping change, etc,.) have been discussed in detail many times in this thread. I encourage you to re-read the posts when you have 3 or 4 days to spare.

shiv

 

Unfortunately I have read this whole thing. Variables like traffic and mountains? Results like time taken to reach certain mphs and g-forces required to do that? Kinda like the torque needed to spin the drum from a certain Rpm to a certain Rpm over a certain time period?
I'm done here also. Top racing teams around the world just do not get it I guess.
I have a challenge for anyone. Try to deceive a customer with trap speeds at the track with a good consistant 60'

 

Here is more interesting reading for those who want to inform themselves on ignition timing and knock.

http://www.innovatemotorsports.com/f...ead.php?t=2099

How does this pertain to the topic?
It gives background information...knowledge is power

 

I think this post is a good summary...

https://www.evolutionm.net/forums/sh...&postcount=488

 

Lol 1 more thing, and its completly OT. I had the post number that relates to this whole thread.... 666

 

I don't understand how one could define "accuracy" in a road tune.... I suppose one could define if a tune was "effective" eg. It made good power and reained an acceptable margin of safety as well as overall driveability. There is no "accuracy" to measure in a tune..... AFAIC, the only way to determine the actual settings of a tune under all sorts of varied conditions, loads, etc., is by measuring the power output, AFRs, boost and more. The only way to measure and accurately record all these factors is with a chassis dyno.

Sure, one could datalog and obtain lots of information. However, the power output as related to all these other paramenters can only be accurately measured with a dyno. Speeds through a 1/4 mile or similar runs are affected by too many factors and uncontrollable variables. While the value of a good road tune is undisputable, the actual results are quite in question until verified.... The value of an equally good dyno tune can be easily quantified and verified on the spot. The road tune without proper verification is just so much guessing, hype and SOP impressions. It's way to easy to exaggerate, brag and otherwise obfuscate the public with a lot of yelling while at the same time trying to discredit your opponent.

Believe me, I've seen the effects and the verified results of "road tunes". They were not pretty. Actually, they sucked and were proven to suck by controlled measurements. Having had a good bit of personal experience with both methods of tuning, I can categorically state that I'd not let anyone "road tune" my car. It's dangerous and involves illegal activity unless you have the use of a large race track. Mostly, it's silly to do it because you have to go to the dyno in order to verfy your results....

Oh yeah, the wind on the highway blows in front as well as behind you and from the sides. Same with the road conditions, gears, throttle positions, etc. It's nothing but a huge crap shoot and not controlled at all. Every load condition can be accurately and repeatably produced on a dyno. There is absolutely no advantage whatsoever from a road tune and possibly and more likely probably a great chance for a screwed up lousy and dangerous hack job.

 

You are obviously a good driver and you have to know that your words are total bull$hit. The only thing that can be proved on the race track with any kind of accuracy is the skill of the driver. I can take a perfectly powerfull car and give you 1/4 mile ets and trap speeds that will make you want to drive it of a cliff. That proves nothing except that I can't drag race very well

 

I said this before, but I dont think anyone got a chance to see it:

IMO: The best tune is one that allows for the most possible horsepower based on safe levels of boost, timing, and air/fuel ratio. When I say, "most horsepower" I do not mean peak numbers, but also the numbers in the mid range. I would gladly take an Evo with 30-40 more whp over an Evo that had just 20-30 peak whp. I also feel that a tune is good if it can be done without the need of expesive aftermarket parts. I like to keep things simple, and if it isnt broke, why replace it?

It doesnt matter how smooth or powerful it feels, its what the dyno and the logged data are telling you how the car is performing. This is exactly what people run into with road tuning. They get this "feeling" and "hype" that the car is "smooth" and "pulling strong". Those terms are very subjective to both the tuner and the customer. What may feel strong to you may not feel strong to someone else. However, when they put their car on the dyno to have this "feeling" quantified into acctual numbers and facts they are brought into the real world. Sometimes its good, and sometimes its bad, but at least they finally have an idea of what they paid for.

I think that brings up a good point. How can you justifiy the price of a tune without knowing any real numbers? How does the customer know when to feel good about the purchase he just made? I for one would not buy a product based on words of "smooth" and "pulls hard". The customer will have really no idea whats going on in the tuning process to feel satisfied with the tune. Whereas with a dyno they can see real numbers in real time. They can ask, "hey, why did my car just make 20whp less than the last pull?" They will be able to see numerous before and after dyno charts along with the tuner. I think with the ability of the dyno to say your car made "X" before and makes "Y" after will give the customer satisfaction his money went to a good cause.


I complete agree with what silverEVO8 says also.

 

Actually, it was an automatic, so everything was consistant.
Even with my evo, I don't launch it for tuning. I floor it off the line. Different strokes for different folks. They don't start the timer until you cross the line.

Ok, since dyno numbers matter so muchto you guys, have you thought about the sensors they use to capture the data? How accurate can those be? Howabout the software that interfaces with it? The computer will smooth the data out so it won't be absolutely accurate either. Those things makes dynos too different from each other, so I personally don't like looking at dyno numbers. And it's so easy to fake numbers also.
To me, it's like everyone trying to define what a unit of force in physics is to them. Since there's no standard, dynos are BS.

And about that F1 evom link, that guy is oversimplyfing that it's just another dyno with simulated conditions.
I mean comeon, they're going to use a dynodynamics or dynojet to tune? rofl... I'm sure there's a bazillion more sensors and equipment. So the closest thing to the real thing, is the tracks.

BTW, my trap speed with and without launching are very similar. Think about that.

 

Yeah right, unless your launch is just as effective as rolling out. If that's the case I suggest tuning your launch, and I bet you will see a higher trap speed.

 

My friend and his mkiv supra TT did it also, because he's afraid of spinning out and hitting the wall. He's a auto also. He trapped all very close 115mph with a 2-3mph tolerance, with and without launch. Anyways, believe it or not, give it a try. I'll try and find my slips, with my slow and faster 60foot. Probably not a good thing to post it in this thread though, it's going to go way off topic.