When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Dyno session # 4 2016 ZO6, stock tune, AFE CAI, Borla mid-pipe, Mamo ported TB Baseline dyno session # 1 stock vs dyno session #4
This 4th dyno test was done this morning. As with previous testing the car is untuned and was driven 200 plus miles after each mod was done and before dyno testing. Mileage included mixed use on 2 lanes and interstate. WOT runs were made on interstate (2) from 50 to 150 plus MPH. WOT runs were made on 2 lane where traffic & conditions permitted. I am not displeased with results particularly the TQ readings on this auto trans car. It is clear to me there is more HP & TQ with a good tune. You can draw your own conclusions in the controversy here over whether the ECU is self limiting. I am not going to get in that argument. Hope this series of tests help others make decisions about these common mods.
First things first, i was wrong that they make the same power as the BMS...
Second thing... I am thankful you are doing a true and fair scientific study on this.
With both of those things said, I am trying to understand what is causing/tricking the car to not run AS RICH. Its evident by the AFR graph below that something is changing in what the car THINKS is going on.
One could say that "the afe is just flowing more air, and thus, that is why it is less rich, and this is proof the car does not think at all" but if THAT were the case, the afe and the BMS and the stock intake/filter would not end up at the same EXACT SAME afr towards the top 1/5 of the RPM scale... they would continue to separate in AFR as RPM would climb, not converge to the EXACT same number (this is proof that the car thinks, but I will not get into this yet because I am still uncertain what is going on that is different. Odds of them going to the exact same afr number at the end, are astronomically slim, if you really stop and think about it.)
My initial gut is that the car was a bit more cool today when you did the afe intake dyno run, and so it kept the TB blade open to full capacity longer during the pull, and shut it later (as i have mentioned, it does not stay open 100%, it closes without us knowing when it sees heat thresholds met)
Either way, there is something going on with your AFE run that fools the car through the first 4/5 of the rpm range, that then the car figures out on the last 1/5 of the WOT pull.
I PM'd you questions about the MAF and its diameter and details about the AFT. Call me when you get a chance, because i have about 10 questions I want to ask in a row. Thanks, Mike
One thing is sure Mike, the tune is stock. I had Hal at Dynosty check it with HP tuners before the first baseline dyno test and compare the fuel, spark advance, torque control, radiator fan control, etc. to a stock 2016 ZO6 tune and everything matched. Then just to make sure I had my dealer run a check and no tune has been done. Will get back to you.
One thing is sure Mike, the tune is stock. I had Hal at Dynosty check it with HP tuners before the first baseline dyno test and compare the fuel, spark advance, torque control, radiator fan control, etc. to a stock 2016 ZO6 tune and everything matched. Then just to make sure I had my dealer run a check and no tune has been done. Will get back to you.
I'm not doubting that you have a stock tune at all, and please dont think i have any animosity for you like i do these guys who argue points over and over for 3 days straight about psi and they still dont have a clue what they are talking about, i know you are unbiased, trying to figure out what makes these cars tick, and at the end of the day, so am i. You and I are fine, I'm the same guy you talked to on the phone last time, we have no problem and I will always treat you with respect as you always do me.
I am just trying to figure out the afr, and why it is different the first 4/5 and changes and becomes IDENTICAL the last 1/5 of the rev range. If they had not converged to the same afr, i would not be so curious/puzzled, but that is a HUGE deal if you really stop think about it. Its mind blowing to me... to be honest. It shows me how much these cars DO monitor afr OR how accurate their tables are set up to add fuel to match a specified/desired AFR by the computer.
While some will be impressed by the power gain... (which, don't get me wrong, im not against gaining the power you show here...)
I AM MOST IMPRESSED.... the car can match AFR on 2 completely different intake systems. Seriously, point that out to your tuner/dyno operator and see if they arent just as mind blown right now as I am. These cars are smart as hell.
Since you can't understand the relationships of pressure, flow, air density etc, it is impossible for you to accurately explain anything. Let's start again with some basic agreements.
1. MAP. If the MAPs are the same at sea level and altitude we are making an apples to apples comparison. The air in this discussion is compressed to the same PSI in the same manifold volume.
2. Oxygen levels are different between the two locations. The gases do not change composition/ratios between sea level and altitude.
3. MAP is atmospheric pressure + Boost pressure (Never once did I state boost pressure was the same as MAP, don't put words in my mouth to make you look smart)
4. Manifold/head/cylinder shape and design are constant as we are dealing with bolt on mods on a LT4.
So lets start with what is happening. As our discussions have revolved around equal MAPs lets start there. The units are irrelevant as long as they are used uniformly. One BAR at sea level is exactly the same BAR at altitude. The MAP is independent of gas composition. It is pressure only. We agree that we need to spin the SC faster to make the MAP at altitude the same as at sea level due to the lower atmospheric pressure at 5000ft. Once the level of SC boost/pressure makes up for the differences in atmospheric pressure between sea level and altitude the pressure, the added compression is the same. We can agree in NA engines the lower atmospheric pressure at altitude is really an issue. However that is not our situation, more boost is needed at altitude to get the same MAP as in your discussion you wanted equal MAP. Also, volume of SC, heads, cylinders is fixed.
So at sea level we can only use air at that density, same for altitude. We agree that air at altitude is less dense for unit volume, meaning less molecules for volume (the ratio of the molecules is the same). So if pressure is the same in both manifolds, the amount of air in them is the same. Doesn't matter what the gas is, the volume of the manifold and pressure is the same between the two engines. So volume of the manifold at sea level if filled with better air (higher oxygen level by weight) at let's say 30 psi. Now we do the same at 5000 ft. Same size manifold pressurized to the same level, 30 psi. However the air at that level has 25% less oxygen by weight. Less oxygen per unit volume means less power.
Oxygen at sea level has about 8.4g/cubic foot and 6.5g/cubic foot at 5000 feet. To get the same weight of oxygen in the manifold at sea level and altitude, in order for you to make the same power you need to cram in a little less than 40% more air at 5000ft. More air in a given volume means more pressure but remember you wanted pressure in the manifold fixed at both altitudes. No where in my discussion did I say you can't make 650 HP at altitude like at sea level (again putting words in my mouth to try to make your point). You need the same amount of oxygen in both situations, you just need more air by volume to get the same weight of oxygen as at sea level. When you put more air in a fixed volume (engine manifold) the pressure increases. So to make it even simpler, a manifold filled with horse s&^t at 30 psi has the same volume and pressure as a manifold filled with gold at 30psi. It may take more work to compress the horse dung but it is still the same pressure in the end.
Now tell me where I am wrong with how much oxygen there is at sea level v 5000 ft in a manifold with a fixed volume and pressure. You can't. Explain to me how the oxygen amount by weight is the same at sea level and altitude. We can do a balanced equation in chemistry or do you not have an understanding of that either? I put it in one of my former posts. Basic take home on that, one molecule of gasoline needs 12 molecules of oxygen. Less oxygen by weight per unit volume at equal pressures means less fuel combusted and less power!
Lesson over, take your books and go home and study!
azgass, im done even reading what you have to say, i wont even read your above paragraph, im sorry
Update, i glanced through it to see if you had the IQ to answer my question yet on where you were speaking on manifold flow speeds, at the maf or at the runners, and you still havent answered.
you are a serious piece of work. I was going to forgive you and give you the courtesy to read your future posts IF you had answered that question, but, you sitll havent. And thus, you are not a person I EVER want to talk to again.
I'm very serious, you and 3z06's stupidity puts me in a horrible mood. If i start a thread (i know this is not my thread) but if i start one, please dont come in it, and I will stay out of yours.
Ah the sign of the unintelligent. Slapped in the face with science and fact and you bury your head in the sand. Oh, BTW the Earth is round not flat, evolution is real and you my friend are a tool! I bet you went crying to mom when someone challenged you. Run away and hide little girl!
sign of an unintelligent person is one who claims they want to help others understand their point of view, who cant even answer wtf they meant when they said "manifold air flow" in their FIRST POST after they've been asked 8 times now, and have posted over 20 times since.
i swear, im not talking to you until you answer that question, by you not answering it, shows you are a total s*** head who's GOAL is to **** people off.
You asked me a load of questions, I answer them all. You don't want to answer 1 question, quit pretending you want to be transparent or want me to understand you, I will not waste another moment talking to you after these final posts.
if temp of the pressurized air in the manifold is equal on both cars at both altitudes, AND map is the same in both manifolds, then air flow into the engine is the same from both manifolds.
you said it is different in your first post.
You were wrong, and instead of admitting you were wrong, like i admitted I was wrong when i was wrong.... you are one of those losers who will type paragraph after paragraph to try to distract people away from where you were wrong, and you have the audacity to say im the one who is missing the boat. You and I are done, i cant stand you buddy. Not only do i think you are wrong, and INSISTENT ON STAYING WRONG, and thus stupid, i think you are also intentionally annoying. You and 3z06zr1 have a ton in common.
3. MAP is atmospheric pressure + Boost pressure (Never once did I state boost pressure was the same as MAP, don't put words in my mouth to make you look smart)
this is the key to where you are missing the boat.
The car does not analyze atmospheric pressure and then ADD another boost value to determine map.
The car has a map sensor in the manifold. it measures THAT pressure, and that pressure has NOTHING to do with outside pressure. IF that pressure is 12.7psi, it is 12.7psi, and it is also 25.84Hg
That manifold can have ANY pressure outside of it... as long as the manifold does not burst, then the 12.7 psi, is 12.7 psi, and that sensor does not CARE let alone KNOW what the outside atmospheric psi is.
12.7 psi will create the same flow into the runners, and will have the same oxygen content, the same amount of oxygen molecules.... as long as it is the same temp air as any other like car and manifold anywhere. they will both make the same HP in that given moment at the same RPM, etc.
The only thign that changes with altitude, is how fast the blower screws had to spin and thus how much work had to be done... to get the air to that 12.7 psi.
If i have a sealed metal tank, and that tank is at 12.7 psi inside, and there is a bar pressure sensor inside the tank, it does not matter if i take the tank to the bottom of the ocean (as long as it does not collapse) it doesnt matter if i take it to outer space, mount everest, the moon, the pressure sensor in the tank will always read 12.7 psi.
It is not a rubber tire where outside pressure matters to inside pressure, it is a metal sealed unit, outside pressure has no relevance to inside pressure, once the screws have done their necessary work to get the air to THAT pressure in the manifold.
You and your followers are too stupid to understand this apparently.
obviously, 12.7 psi is not a pressurized situation at sea level, and that is why i used the 20psi number instead, in all of my descriptions prior. im using 12.7 so you and anyone as dumb as you are can see the chart below and understand how stupid you are right now, and you keep talking down to me saying i dont understand pressure. You are a joke buddy.
Yes I said manifold air flow. I know there is no direct sensor for that. Flow does not equal pressure. I know you are smart enough to know that. Those principles apply to systems dealing with gas and fluid dynamics. What I was stating is a general comment on pressure and flow.
So as you posted above, again you are wrong.You keep changing your story and variables. Stop before you type. I know MAP (manifold ABSOLUTE pressure) is a direct measurement. What are the two determinates of MAP. You know this as well as I do, it is a sum of all the pressures inside the manifold. The two pressures that make up MAP (even though both are not directly measured) are atmospheric and boost. If atmospheric pressure is 12 psi at altitude and 14 at sea level, and the supercharge makes 10 pounds of boost, you have 22psi and 24 psi respectively. That is why you need more boost at altitude to get the same MAP as at level. If you can think of another pressure that contributes to this please let me know. You and I can agree that boost is a measure above atmospheric.
Think more. MAP is after the screws, correct. The flow sensors are in front, pre SC. So once the vacuum pulling air in, as this is not a ram air system, is the same in both situations (sea level v. altitude) the air flow (speed) will be slightly faster at altitude as the density and viscosity of air at altitude is less. I made no direct reference to volume of flow, just velocity. Think of the flow of 5w-30 v 10w-50. Once the exerting pressure is the same the velocity of the fluids will be inversely proportionate to viscosity.
Now, once in the manifold and pressurized there will be very subtle differences in velocity of intake gases exiting the manifold in common automotive applications. There are many other variables in place, runner length, diameter, valve timing/lift etc. Those items will be more restrictive than differences in gas/air viscosity. Radius of any tube for flow contributes to these restrictions by a power of 4. That is a different discussion in the topic of power production. Now bigger CAI systems and larger headers reduce the resistance to flow or the change in pressure needed to make a certain volume of flow, but we are talking about SC and air/oxygen at altitude.
This discussion was on started power production of modifications and evolved into an exchange on the impact of altitude.
First things first, i was wrong that they make the same power as the BMS...
Second thing... I am thankful you are doing a true and fair scientific study on this.
With both of those things said, I am trying to understand what is causing/tricking the car to not run AS RICH. Its evident by the AFR graph below that something is changing in what the car THINKS is going on.
One could say that "the afe is just flowing more air, and thus, that is why it is less rich, and this is proof the car does not think at all" but if THAT were the case, the afe and the BMS would not end up at the same EXACT SAME afr towards the top 1/5 of the RPM scale... they would continue to separate in AFR as RPM would climb, not converge to the EXACT same number (this is proof that the car thinks, but I will not get into this yet because I am still uncertain what is going on that is different. Odds of them going to the exact same afr number at the end, are astronomically slim, if you really stop and think about it.)
My initial gut is that the car was a bit more cool today when you did the afe intake dyno run, and so it kept the TB blade open to full capacity longer during the pull, and shut it later (as i have mentioned, it does not stay open 100%, it closes without us knowing when it sees heat thresholds met)
Either way, there is something going on that fools the car through the first 4/5 of the rpm range, that then the car figures out on the last 1/5 of the WOT pull.
I PM'd you questions about the MAF and its diameter and details about the AFT. Call me when you get a chance, because i have about 10 questions I want to ask in a row. Thanks, Mike
Mike,
I have a question on AFR but not sure how to ask it but here it goes. I have the BMS, PTB, and X-pipe. I can monitor my AFR and it appears when I go WOT the AFR is commanded to 12:5 but I didn't run it out to 6500. So in the graph above is his AFR rich because as RPM and boost increase and with more airflow from the CAI/ PTB the ECU keeps adding fuel based of of inputs from the MAF? I know the MAF doesn't see PTB. I ask because I bet I am running rich as well, I have the stock tune.
Mike,
I have a question on AFR but not sure how to ask it but here it goes. I have the BMS, PTB, and X-pipe. I can monitor my AFR and it appears when I go WOT the AFR is commanded to 12:5 but I didn't run it out to 6500. So in the graph above is his AFR rich because as RPM and boost increase and with more airflow from the CAI/ PTB the ECU keeps adding fuel based of of inputs from the MAF? I know the MAF doesn't see PTB. I ask because I bet I am running rich as well, I have the stock tune.
i will answer your question IF i can figure out what that answer is, right now I believe any answer i give would be ignorant, there are mystery variables at play that I have not figured out yet which allow the afr to be different but then converge to the same value of what looks to be 10.8. As soon as i figure out why the AFE and the BMS and the stock filter, start out different, and then go to the same AFR toward the end, which is MIND BLOWING that the car is that smart. once i have an answer how its doing all of this, i will let you know.
small corrections tho, the maf does see the PTB IF the ptb is allowing for more air to flow and at a faster pace (which it probably makes a very small difference)
if temp of the pressurized air in the manifold is equal on both cars at both altitudes, AND map is the same in both manifolds, then air flow into the engine is the same from both manifolds.
you said it is different in your first post.
You were wrong, and instead of admitting you were wrong, like i admitted I was wrong when i was wrong.... you are one of those losers who will type paragraph after paragraph to try to distract people away from where you were wrong, and you have the audacity to say im the one who is missing the boat. You and I are done, i cant stand you buddy. Not only do i think you are wrong, and INSISTENT ON STAYING WRONG, and thus stupid, i think you are also intentionally annoying. You and 3z06zr1 have a ton in common.
We haven't talked temp in any previous post so don't add that into the mix. You talked 45deg for triggering the code so at no point did we talk temp changes. There is no where in the description of gas laws where flow is discussed. All you can relate from temp, pressure, number of molecules and volume of a system. Now if you said you have 1 minute to fill the manifold with enough air to get a psi of 30 then we can discuss flow. Flow is mph, ft/sec, m/s you pick.
We haven't talked temp in any previous post so don't add that into the mix. You talked 45deg for triggering the code so at no point did we talk temp changes. There is no where in the description of gas laws where flow is discussed. All you can relate from temp, pressure, number of molecules and volume of a system. Now if you said you have 1 minute to fill the manifold with enough air to get a psi of 30 then we can discuss flow. Flow is mph, ft/sec, m/s you pick.
if you go back and read, my big posts, i said temp constant. Right now i am researching other things or i would find and quote it.
See dyno sheet below 2nd dyno session overlay of best run from 1st dyno session.
so above is the BMS filter run, vs the stock filter run. Can anyone tell me what MAF is used in the AFE? is it stock or is it a larger diameter or does it have one at all? Thanks.
if you go back and read, my big posts, i said temp constant. Right now i am researching other things or i would find and quote it.
I know you wanted it constant and we have kept it out of the discussion. No disagreeing with that at all. I still stand behind my statement that the flow (speed of the gases) does not determine pressure in the manifold. It is the volume of gas placed into the manifold.
I know you wanted it constant and we have kept it out of the discussion. No disagreeing with that at all. I still stand behind my statement that the flow (speed of the gases) does not determine pressure in the manifold. It is the volume of gas placed into the manifold.
and this statement you just said, I have agreed and stated MANY TIMES, as long as you admit it is only true AT THE MAF, and not at the runners.
Dont make me go back and quote how many times i said MAF speed will be different but RUNNER speed will be the same.
Which is why i asked you to clarify which you were speaking on, 8 god d*** times, and you never would, for whatever reason, i still don't know.
08-13-2018, 08:54 PM
