Magic boosted clouds!!!!!

I am trying to illustrate co-incidental assumptions vs causal assumptions.

Boost tells you a lot, but within parameters you have to add to make it meaningful, mass air flow tells you everything...all by itself.

 

How about this (for electrical guys).... boost is Ohms, flow is Current

 

This has been my point all along - why do you keep arguing with me about it ?


IF it's acurate it is a VERY valuable parameter . It doesn't tell you everything though , and I can give you examples of why that is .

 

thats the key difference between the two sides of this discussion.

Every other means requires multiple pieces of information to make accurate measurement. MAF needs only one, tube cross-section(diameter), and that is a static, stupidly easy to acquire number.

Every other method can work just as effectively, but the more elements you add to the equation, the more room for error you gain

 

How is it more or less accurate than a boost gauge? They all use a 1-5V scale. Have you ever calibrated a MAP sensor? I know I have, and they were off by a lot.

 

I think its because those parameters are at least somewhat variable from car to car. No different than trying to compare dyno numbers from two different dynos on two different days. Its ballpark and gives you an idea...but there are better ways to compare.

 

And Pressure Differential is Volts....

Don't laugh, this is actually how I had to teach my self electricity 101....

 

Quote "Because it is a dangerous oversimplification..."

I agree , but Only if you don't understand what else is going on .

 

Just had to change the order of posts.....

 

If pressure is such a good measurement.... then why does the RX8 have an IAT and a Baro sensor?

* No cheating if I have already told you why *

 

no one is saying what you always propose is wrong, or cannot work.

It is just not the easiest and most foolproof way to do things.

What is easier, an equation with 3,4,5,10 variables.... or an equation with ONE?

 

I don't see any difference between comparing different dyno numbers than different MAF voltages, it's just as flawed to me

 

Yep, but at least the manufacturer and type is the same, and it's free.

 

PDXHAK has posted his dynos . I came on here and said i think there is still an issue . The reason I believe this is because I see two parameters out of whack with eachother .


Those two parameters are boost profile and a WHP dyno .

So - unless you believe his dyno is fine then you have to agree that PSI was a usefull thing to know ...



YES ?

 

I guess we have to go with whatever is the LEAST flawed and in my book that would be dyno numbers .

 

How is the dyno the least flawed?

Every RX8 comes from the factory with an identical MAF sensor that is electrically calibrated identically. The only variable is MAF tube diameter.

Dyno's are all different manufacturers, it is common knowledge there are fairly large differences in calibration, in some cases even the same dyno provides conflicting numbers when all other logged data is identical, etc etc

EDIT: I just had to correct major grammar errors(repeating words etc) I think that is my cue to say I'm too fucked up to be a part of this any more tonight. You guys have fun :P

 

Which logged parameter most closely matches the power output of this motor?



It is the MAF, not the boost profile.....

the 375 g/sec the MAF is reporting would NOT be a cause for concern if the Volts were also in the 4.6-7 or higher range. However, if the reported Volts is 3.3-3.5, then that makes the dyno pretty accurate and then you can trouble shoot the set-up of the car.

Boost only matters because you think you know the turbo and flow in question (and therefore the temp and pumping losses).... if it was a GT35 at that PSI, then what would you say, how about a TD06-18G, or a K03? or a (you see where I am going with this...) OR if it were 100F outside, or 30F?

 

Just to be clear here .
Kane - do you think all is rosy with pdxhak's dyno or not ?

 

I want to see volts....


Barring that, then I'd want to tune his BC gain up to keep MAF curve moving upwards. If he can hit 4.7V or higher, then I'd say it is fine mechanically, and the issue is in the tune.

 

I just double checked an older log, a Greddy car I tuned that hit 271 on the Dyno, had a MAF Voltage of 4.61.... that is just about perfect based off every MAF V log I have reviewed...

So if the Volts aren't up there, then something is wrong.

 

well we don't have volts . so what shall we look at then ?

hmmmmm

 

I am doing Managerial Accounting.... (makes me want to kill myself).

You can go look at pr0n I guess....

 

The clouds! I think.....

 

Here figure out what is wrong with this car.....

 

haha - lucky you have this forum to come to get some light relief .