MAF Flow rates

Myx

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Why do you think you were under-shooting your boost target by that much? Or was that screen taken just before hitting the target?
Your guess is as good as mine. That's why I'm always reading in here and any documentation I can get my hands on. Actually just fell asleep looking at Power's pic and mine at my desk. Oops! :rofl:
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PowerPerLiter

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Why do you think you weren't hitting your boost target? Or was that screen taken just before hitting the target?
Turbo is out of breath. Only way I made my mapping match on the big end is by delaying commanded boost until 4500. There is a fine line to walk here. Command too much boost early in the rev range and it will spike and then taper as rpm climbs. You have about a 2500-3000 rpm of power window via boost pressure with the stock turbo. Want it low in the revs it wont stay around up top. My boost table was created to simulate a laggier turbo and keep it held until 6000+ then I dramatically lowered boost command to try to open the wastegate for more mass flow out of the exhaust side of the engine (my thinking was the turbo isnt keeping up anyway so may as well relieve some backpressure and run the timing advance higher.)
It worked for me.
 
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Myx

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Dam Myx that thing is cookin!

Strange when comparing the afm.c (in my pic) to the Mg/stk of yours. That is the reported airflow per stroke of the piston. Weird to see your maf g/s be that much higher without a corresponding higher number of "cylinder fill".

Just kinda proves my point that the data doesnt always reflect expected power output with these cars.
Exactly! Probably wouldn't be a straight comparison anyways, since at 68mph, due to my smaller diameter tires, I'm at a higher rpm (6388rpm vs 5270rpm). So even with exactly the same modifications, it should be more airflow at 6388 vs 5270rpm. Then there's that dilemma with these cars as to where the peak hp is. Some is at 6k, some just above 6k and some at 5500rpm or lower. Lot's to think about.
 

Myx

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Turbo is out of breath. Only way I made my mapping match on the big end is by delaying commanded boost until 4500. There is a fine line to walk here. Command too much boost early in the rev range and it will spike and then taper as rpm climbs. You have about a 2500-3000 rpm of power window via boost pressure with the stock turbo. Want it low in the revs it wont stay around up top. My boost table was created to simulate a laggier turbo and keep it held until 6000+ then I dramatically lowered boost command to try to open the wastegate for more mass flow out of the exhaust side of the engine (my thinking was the turbo isnt keeping up anyway so may as well relieve some backpressure and run the timing advance higher.)
It worked for me.
This sounds like a Ktuner Stage 2 vs TSP Stage 1 strategy and what people have been reporting.
 

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Why do you think you weren't hitting your boost target? Or was that screen taken just before hitting the target?
That was just a blip in time. Will try to get the whole log up. Here is another shot at 75.8mph. As you can see, boost pressure is actually slightly more than the target (22.5 vs 22). My ignition advance is pretty aggressive (I think).

Honda Civic 10th gen MAF Flow rates Virus
 


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Myx, that's exactly right about TSP. I know when I made my move from Hondata to KTuner I was initially amazed at the much more potent KTuner low end. Then, when I gunned it a high speed I was let down by what felt like noticeably less grunt than I had with Hondata. I felt like I was between a rock and a hard place. I preferred KTuner's low end and driveability but wanted the Hondata highway ooomph.

Over a year and a half ago, I PM'ed TSP about considering doing a tune for us non-Si guys. And lo and behold after a long wait they actually did. Derek's tune is all about balance. From bottom to top I can't imagine a better canned tune. Best of Hondata and KTuner combined.
 
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Thanks guys this explains a lot to me.I'm used to the older honda's .So i guess the only way to really tell if i made some gains is to dyno it.
I also noticed the MAF flow rate peaks at around 5500rpm and then goes down.
 
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Dam Myx that thing is cookin!

Strange when comparing the afm.c (in my pic) to the Mg/stk of yours. That is the reported airflow per stroke of the piston. Weird to see your maf g/s be that much higher without a corresponding higher number of "cylinder fill".

Just kinda proves my point that the data doesnt always reflect expected power output with these cars.
At the same flow rate (g/s) the cylinder fill (mg/stk) will be lower as revs increase (because X amount of g/s will fill the cylinder more times at higher RPM, so lower mg/stk)
g/s is a good indication of Power output (or at least power potential / AF, IGN etc depending ofc)
mg/stk is a good indication of Torque output

Your MAF scale is very well calibrated because you hit your A/F target with minimal STFT/LTFT

Myx's on the other hand is not that well calibrated because his combined STFT+LTFT is ~ -7% and still runs 0.1AF richer than the target, so he is ~ 8-9% off at that spot. Remove 8% from his g/s and you get the same flow as yours :)
On the other hand he runs 6.5 degrees of IGN which is awesome, but I don't like the fact that he targets 22.2psi of boost which the stock turbo will never hit at that rpm. I think he can benefit from targeting 20.5 to keep the WG more open like PowePerLiter suggested.

interesting talk altogether :)
 

Myx

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At the same flow rate (g/s) the cylinder fill (mg/stk) will be lower as revs increase (because X amount of g/s will fill the cylinder more times at higher RPM, so lower mg/stk)
g/s is a good indication of Power output (or at least power potential / AF, IGN etc depending ofc)
mg/stk is a good indication of Torque output

Your MAF scale is very well calibrated because you hit your A/F target with minimal STFT/LTFT

Myx's on the other hand is not that well calibrated because his combined STFT+LTFT is ~ -7% and still runs 0.1AF richer than the target, so he is ~ 8-9% off at that spot. Remove 8% from his g/s and you get the same flow as yours :)
On the other hand he runs 6.5 degrees of IGN which is awesome, but I don't like the fact that he targets 22.2psi of boost which the stock turbo will never hit at that rpm. I think he can benefit from targeting 20.5 to keep the WG more open like PowePerLiter suggested.

interesting talk altogether :)

Here is one more for a better look. The pic is at 68mph. It's of my finished Boostane (Premium) tune. The pic above is something I was testing off another tune while I added Boostane (Pro) with more ignition advance. The attached pic is what I will be using at the track. The one above is just me testing some things and will probably test it at the track once I get some things ironed out.

Honda Civic 10th gen MAF Flow rates Tune
 

varge

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Here is my own example

My actual MAP is following close to target and my EWG position is not very tight. I am ~2% off the target AF so I am doing a bit less than 165g/s.
Do note that STFT is 0 as the Fuel Stat is 4 (open loop for EUDM)

Honda Civic 10th gen MAF Flow rates upload_2020-2-29_17-52-40
 


varge

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Here is one more for a better look. The pic is at 68mph. It's of my finished Boostane (Premium) tune. The pic above is something I was testing off another tune while I added Boostane (Pro) with more ignition advance. The attached pic is what I will be using at the track. The one above is just me testing some things and will probably test it at the track once I get some things ironed out.

This one is a lot better and much more refined, it actually rocks lol :)
It shows the improved flow that the Si turbo and you intake are producing … if I could take a wild guess, I would say you are in the 240whp range
 
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Myx

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This one is a lot better and much more refined, it actually rocks lol :)
It shows the improved flow that the Si turbo and you intake are producing … if I could take a wild guess, I would say you are in the 240whp range
Thank you for your (As well as others here) analysis. I almost forgot I had a test tune in the car. I just finished reflashing back to the finished tune. Still more testing to do even with this tune.

Really liking this thread and continuing to learn much.
 

PowerPerLiter

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At the same flow rate (g/s) the cylinder fill (mg/stk) will be lower as revs increase (because X amount of g/s will fill the cylinder more times at higher RPM, so lower mg/stk)
g/s is a good indication of Power output (or at least power potential / AF, IGN etc depending ofc)
mg/stk is a good indication of Torque output

Your MAF scale is very well calibrated because you hit your A/F target with minimal STFT/LTFT

Myx's on the other hand is not that well calibrated because his combined STFT+LTFT is ~ -7% and still runs 0.1AF richer than the target, so he is ~ 8-9% off at that spot. Remove 8% from his g/s and you get the same flow as yours :)
On the other hand he runs 6.5 degrees of IGN which is awesome, but I don't like the fact that he targets 22.2psi of boost which the stock turbo will never hit at that rpm. I think he can benefit from targeting 20.5 to keep the WG more open like PowePerLiter suggested.

interesting talk altogether :)
Yeah I was pretty anal about afm calibration for a while: this screenshot of the trims was even during warm up lol

Also just cause we are having fun with data Im posting some randoms that were in my phone still the second pic down is when I was finding the max "happy boost" (key notes is how much target had to overshoot to get there as well as look at the timing difference from these to.

The last one was a custom file while using the factory boost table
Honda Civic 10th gen MAF Flow rates Screenshot_20190419-114342_Hondata
Honda Civic 10th gen MAF Flow rates 20190620_192222
Honda Civic 10th gen MAF Flow rates 20190415_222938
 
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PowerPerLiter

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Man I really wish I could convince myself to tune my new car. I had so much fun with this shit.
 


 


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