Calculating Correct Torque - Working Out RWHP/RWKW

[BigDaddyCool]

So I just want to throw this out there...... while alot of my posts maybe a bit of a waste I'm all for learning as much as possible about tuning.

So I had my car tuned professionally mafless, and it sucked....... both driving and the power output on the dyno. So I threw the tune out aside from the VE table that was done........

Now I threw my maf back in, clearly if you just throw random numbers in it...... and log Engine Torque or Delivered Torque those results will be skewed by two factors....... what the car thinks in coming in eg. airflow g/sec and timing as per the 'maximum torque' calculation spark table.

So relying on just monitoring those two things dont ultimately help so I thought of another idea. Regardless of the 'numbers'........ there's only one true way of knowing for sure if you are 'getting more out of it'........ and thats MAF Hz...... Because more airflow = higher maf hz...... regardless of anthing else is means more air is coming in to cool that little wire.

Now eg. my mafless dyno tune...... ran constant 460-480nm's.... on the scanner, max MAF Hz read of around 9800hz....... (just example, wont go into all the hows and compliations and the rest)........ since retuning...... my tune runs 550nm's on the scanner, producing more around 10350hz at present.... i'm trying to stabilise manifold pressure somewhat with timing and fueling....... because I know I can get it to around 10650....

So would all the 'advanced' tuners agree......... if nothing else........ higher maf hz = more air in, more air out....... regardless of any other readings.

You can use all the various sites then to run estimates of power at engine vs whats lost to come out with a RWHP/RWKW...... Helps I guess if you have your car dyno'd so you know where it 'was' before you try to get more I guess...... otherwise your flying blind.

[LSX378]

If you are running a stock intake and MAF and the MAF cal is factory, yes more Hz = more airflow generally. Change the intake ducting prior to MAF and MAF cal would need to be revised.

[BigDaddyCool]

If you are running a stock intake and MAF and the MAF cal is factory, yes more Hz = more airflow generally. Change the intake ducting prior to MAF and MAF cal would need to be revised.

Ya I'm not referring to calibrating it more what it does..... higher hz is a physical thing..... more air cooling the wire etc

[S2H]

So I just want to throw this out there...... while alot of my posts maybe a bit of a waste I'm all for learning as much as possible about tuning.

So I had my car tuned professionally mafless, and it sucked....... both driving and the power output on the dyno. So I threw the tune out aside from the VE table that was done........

Now I threw my maf back in, clearly if you just throw random numbers in it...... and log Engine Torque or Delivered Torque those results will be skewed by two factors....... what the car thinks in coming in eg. airflow g/sec and timing as per the 'maximum torque' calculation spark table.

So relying on just monitoring those two things dont ultimately help so I thought of another idea. Regardless of the 'numbers'........ there's only one true way of knowing for sure if you are 'getting more out of it'........ and thats MAF Hz...... Because more airflow = higher maf hz...... regardless of anthing else is means more air is coming in to cool that little wire.

Now eg. my mafless dyno tune...... ran constant 460-480nm's.... on the scanner, max MAF Hz read of around 9800hz....... (just example, wont go into all the hows and compliations and the rest)........ since retuning...... my tune runs 550nm's on the scanner, producing more around 10350hz at present.... i'm trying to stabilise manifold pressure somewhat with timing and fueling....... because I know I can get it to around 10650....

So would all the 'advanced' tuners agree......... if nothing else........ higher maf hz = more air in, more air out....... regardless of any other readings.

You can use all the various sites then to run estimates of power at engine vs whats lost to come out with a RWHP/RWKW...... Helps I guess if you have your car dyno'd so you know where it 'was' before you try to get more I guess...... otherwise your flying blind.

yes and no....

in general more MAF Hz = More air...but not always...
the MAF measures air density...many factors play a role in actual air density


as far as using it to measure power and torque....its just not that simple.
you can have an engine that gulps a lot of air but makes less power than a 2nd engine that gulps less air because the tune on yours is off and the tune on # 2 is spot on.


then comes the matter of measuring power...
which unfortunately is not exactly a simple piece of math...otherwise we would all be able to accurately measure Horsepower very easily in our scanner.
when it comes to Horsepower...its Force = Mass x Acceleration.. but mass is in Slugs, and Acceleration is in Angular Momentum(which is hard to measure in terms of how fast a car is moving forward.)
on top of that.. its also about the Rate of acceleration not just a static value....meaning its the measurement of the difference between rate of accleration of moment one vs Rate of acceleration of moment two.

back to your issues....

what are you trying to accomplish...
are you trying to determine power? or are you trying to figure out if your tune is off?

stabilizing manifold pressure...is not something you can do, and its pointless to try to do...
its not physically possible as the air has to enter thru pulses...if it doesnt, you cant have combustion

as far as your previous tune that "sucked for both power and driving"
there are many factors at play..
I can make the MAF and VE(SD) make the same amount of power... there should be no difference when it comes to total power output.
what you will find is that a car tuned to run full MAF(not a blend like stock) will be a bit smoother but at the cost of not as crisp of throttle response.
and a Car tuned all VE(No MAF) will tend to have a crisper and snappier throttle but at the cost of being not quite as smooth as stock
hence forth the reason for having both...you get the benefits of VE(SD) and MAF operation blending together
and unless you tune both tables properly, you will still see issues with power and driving

[BigDaddyCool]

Nice post cheers. and there is a 'yes and no' to the manifold pressure stabilising..... no you cant get it perfect but yes in that you can upset it via fueling and spark changes which is what you dont want. I have sorted out the dips in manifold stuff now...... it's very important to make sure the manifold holds whatever maximum pressure you can get from it preferably all the way thru a wot run..... if it dips in pressure as in the map drops it in a wot run it will dip in power.

My goal is simple, tuning correctly is fine...... but it will never give you 'maximum power'....... to get 'max power' you need to get a little creative here or there to tweak things where you can, so thats what i am doing to obtain the most torque across the 'drivability range' of where I can accomplish it.

My aim is simple in my tune........ 500+ nm of torque from 2500rpm held til 5000rpm. I wish to keep the car on the torque from those two spots. My professional tuner for some reason couldn't do it..... he just didn't try if you ask me so...... I'm already very close with a peak torque of 555nm on the scanner compared to his 480nm on the scanner.

But ...... to answer your question..... numbers on scanners are just that so I'm trying to 'make sure' that....... I am 'making more power' and it's not just in my head by numbers produced on VCM Scanner..... etc. I do all the various maths surrounding it all .... I intend to dyno the car in the next few weeks to see if I'm up on my professional tuners tune to make sure it is 'making more power' before spending more time on it. It's right near where it should have been when he did it now so.

(manifold pressure to me is like torque. As they say 'torque will get you there' ........ same goes with pressure, you loose pressure you loose power')

[S2H]

the #'s in the scanner are calculated based on multiple variables.....
you cannot use it to compare because it will vary from day to day and run to run.....
air temp will change it, a spark change will change it....
there is absolutely ZERO accuracy of the #'s... they dont mean anything except to the internal math of the car for Transmssion stuff and internal Diagnostics...nothing else