MAF vs SD
Hmm you might be outrunning the MAF filter. I might put the MAF Airmass Filt up to 0.1016 and monitor for differences. None of this is measurable on this older PCM so its a change and observe sort of thing.
Can you explain this setting? I find no info online about it's effect.
I see .1016 is common in a truck file......
Its one of probably a couple thousand first order lag filters in the software that take noisy signals and smooth them out. Essentially every sensor on a vehicle (or any piece of equipment or hardware) has some sort of filtering going on. The equation is MAF_f = filt_coeff*(MAF_t - MAF_t-1) + MAF_t-1 where MAF_f is the filtered estimate, filt_coeff is that 0.1016 number, MAF_t is current MAF sensor reading and MAF_t-1 is the previous MAF sensor reading. Updated on a 12.5ms raster if I remember right. Only a small fraction of the new sensor reading gets added to the running estimate each time it updates so it is less affected by random noise. In your case, in 1st gear you're revving a lot faster than the stock engine did, so that small fraction might be too small to keep up with the rapidly increasing airflow values. 2nd gear revs slower, so the problem goes away more or less. That's my prognosis of that issue anyway lol.
Understood. Filters we used to do with resistors, capacitors and inductors. 😊
This will be interesting to experiment with.
My Corvette already has that number in it, and does the same thing.
Could be an argument for SD tunes being the way to go.
I’m a little puzzled why I’m the only guy noticing this?
This will be interesting to experiment with.
My Corvette already has that number in it, and does the same thing.
Could be an argument for SD tunes being the way to go.
I’m a little puzzled why I’m the only guy noticing this?
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Understood. Filters we used to do with resistors, capacitors and inductors. 😊
This will be interesting to experiment with.
My Corvette already has that number in it, and does the same thing.
Could be an argument for SD tunes being the way to go.
I’m a little puzzled why I’m the only guy noticing this?
This will be interesting to experiment with.
My Corvette already has that number in it, and does the same thing.
Could be an argument for SD tunes being the way to go.
I’m a little puzzled why I’m the only guy noticing this?
A lot can be solved on the fuel to wall impact factor. Make small adjustments to the high MAP areas to solve lean tip in, and conversely, make small adjustments to the low map areas to solve rich tip outs.
The VE table is also where the PCM looks during rapid transitions, so having a good VE map is key to smooth revs. Your problem sounds like a transient issue in addition to the MAF filtering smokeshow so eloquently described. I’d try multiplying the 100 row on the fuel to wall impact table by 1.1 and blending it down to the 50 row.
That table is all about prediction, and since the MAF is essentially “behind” all the time, adding some predicted fuel on fast revs should help.
Appreciate the advice. I’ve been tuning a long time, still learning.
The VE tables on both cars are untuned. So I’ll do that on the Olds.
My corvette has the dual VE tables. I have an 02 file ready for it, just haven’t done it yet.
The VE tables on both cars are untuned. So I’ll do that on the Olds.
My corvette has the dual VE tables. I have an 02 file ready for it, just haven’t done it yet.
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From: Virginia
Constantly learning is what it’s all about. You and I share that “pickiness” when tuning, which opens up rabbit holes of learning opportunities.
In all honesty I don’t know if fuel transients will fix your issue completely, but logically thinking, they would play a big part in it. It’s just that those tables are often overlooked or misunderstood.
In physics, when vacuum increases (aka RPM rate in your case) fuel evaporation increases. So it’s logical to think when you are spooling faster, fuel is atomizing faster, therefore requiring more fuel in the calculation. That formula bugged me for quite some time trying to figure out how much pulse is a result of the transient tables. I never did solve it because you can’t use a user math to reference another user math so the formula got too complicated for the software, thus ending my progress on that.
Sure would be cool if we could do that @HPTuners. Just a humble suggestion.
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I have zero doubt in your abilities. The fact you even noticed an “error” indicates your attention to detail many wouldn’t even notice. I’ve seen you on here a long time and I have learned from your posts as I’m sure many have.
Constantly learning is what it’s all about. You and I share that “pickiness” when tuning, which opens up rabbit holes of learning opportunities.
In all honesty I don’t know if fuel transients will fix your issue completely, but logically thinking, they would play a big part in it. It’s just that those tables are often overlooked or misunderstood.
In physics, when vacuum increases (aka RPM rate in your case) fuel evaporation increases. So it’s logical to think when you are spooling faster, fuel is atomizing faster, therefore requiring more fuel in the calculation. That formula bugged me for quite some time trying to figure out how much pulse is a result of the transient tables. I never did solve it because you can’t use a user math to reference another user math so the formula got too complicated for the software, thus ending my progress on that.
Sure would be cool if we could do that @HPTuners. Just a humble suggestion.
Constantly learning is what it’s all about. You and I share that “pickiness” when tuning, which opens up rabbit holes of learning opportunities.
In all honesty I don’t know if fuel transients will fix your issue completely, but logically thinking, they would play a big part in it. It’s just that those tables are often overlooked or misunderstood.
In physics, when vacuum increases (aka RPM rate in your case) fuel evaporation increases. So it’s logical to think when you are spooling faster, fuel is atomizing faster, therefore requiring more fuel in the calculation. That formula bugged me for quite some time trying to figure out how much pulse is a result of the transient tables. I never did solve it because you can’t use a user math to reference another user math so the formula got too complicated for the software, thus ending my progress on that.
Sure would be cool if we could do that @HPTuners. Just a humble suggestion.
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The truth of the matter is that almost nobody notices or cares about some of the minor variables that others of us will endlessly chase down the rabbit hole. Most of the old school guys from carb days are just happy to be able to idle, and a lot of the new keyboard commando types want a plug and play "stage whatever #" installed by a shop. It leaves a small window of years for people that understand both the mechanical and electronic aspects of what is possible. If you want to be really infuriated, read some motorcycle forums. The typical members of those are approximately 20 years behind the car forums on their understanding of engine technology on the electronic control side of things. Most of the new factory rides are still Alpha-n, with maybe a baro correction.
I seriously wonder at this point how the op feels about this post at this point considering he asked a “simple” question lol. Not so simple as he rightly pointed out. At this point this thread has been straight hijacked lol. I’ve seen no reply’s or questions so far. He just dropped a bomb and dipped out. Good for him. @imaswfan
Big facts here. Most people are just most people and for the lack of a better term, not horsepower nerds lol. I like going fast. I like fast cars. Driving them, tuning them, building them, etc. We’re all nerds for horsepower here. Sucks if you don’t like math because the results are horsepower in the end.
I seriously wonder at this point how the op feels about this post at this point considering he asked a “simple” question lol. Not so simple as he rightly pointed out. At this point this thread has been straight hijacked lol. I’ve seen no reply’s or questions so far. He just dropped a bomb and dipped out. Good for him. @imaswfan
I seriously wonder at this point how the op feels about this post at this point considering he asked a “simple” question lol. Not so simple as he rightly pointed out. At this point this thread has been straight hijacked lol. I’ve seen no reply’s or questions so far. He just dropped a bomb and dipped out. Good for him. @imaswfan
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From: Virginia
Dude may have dipped out, but I appreciate when someone starts a thread that leads to intelligent discussion. To add to the hijacking, a lot of the info on this forum relates to 1/4 mile runs, and as such, the transient tables are never involved. You just make your SD and or MAF table match what happens at your current rate of acceleration, and you are done. No need to worry about what happens if you are driving down the interstate and suddenly tip into one of those tables.
The difference is all of us are actual tuners, and “overlog” the **** out of our cars. When I do a customer car, I get it to run right, test it to try to work out the bugs, take my time and get it back to them when I’m satisfied. That’s my “full tune” package when going into it. Difference is on my own car, I’m almost literally never satisfied lol. If I see a number outside 5% anywhere on my tables I’m suddenly concerned.
I’ve made a **** ton of folks happy with their cars, but I’m never happy with mine for some reason lol. If I took the gauges out and stopped logging stuff I’d have no idea. But for some reason I don’t on my toys, but hey, it drives me to learn new things so I can’t be mad about that.
You are getting it, as I’m sure Ron (my name is also Ron so I notice his posts) and smokeshow already know, just doing the airmass models will NOT solve your problems in all conditions. Obviously. Logs above to prove it courtesy of (the other) Ron.
The difference is all of us are actual tuners, and “overlog” the **** out of our cars. When I do a customer car, I get it to run right, test it to try to work out the bugs, take my time and get it back to them when I’m satisfied. That’s my “full tune” package when going into it. Difference is on my own car, I’m almost literally never satisfied lol. If I see a number outside 5% anywhere on my tables I’m suddenly concerned.
I’ve made a **** ton of folks happy with their cars, but I’m never happy with mine for some reason lol. If I took the gauges out and stopped logging stuff I’d have no idea. But for some reason I don’t on my toys, but hey, it drives me to learn new things so I can’t be mad about that.
The difference is all of us are actual tuners, and “overlog” the **** out of our cars. When I do a customer car, I get it to run right, test it to try to work out the bugs, take my time and get it back to them when I’m satisfied. That’s my “full tune” package when going into it. Difference is on my own car, I’m almost literally never satisfied lol. If I see a number outside 5% anywhere on my tables I’m suddenly concerned.
I’ve made a **** ton of folks happy with their cars, but I’m never happy with mine for some reason lol. If I took the gauges out and stopped logging stuff I’d have no idea. But for some reason I don’t on my toys, but hey, it drives me to learn new things so I can’t be mad about that.
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My first experience with a "tuner" was around 2003. He was a thieving hack who put canned "tunes" into customer vehicles that I later found out were identical to stuff that was floating around the internet. He had quite the good reputation on many forums, because few people knew any better back then. Just for reference, it was an ******* out of San Antonio known as Nelson. He actually cut my electric fan wires while "tuning" my Whippled work truck. He also screwed up the blower bypass valve so that it only made about 2# of boost. I saw people on internet forums singing his praises out of sheer lack of knowledge. After that, I decided to learn things for myself.
The best example perhaps is our glorious OP, who asked a complex question, involving many factors, and has yet to grace us again with his decision. He’s actually thinking he can get 550 whp out of what he has with stated planned mods. He must be assuming someone can “tune in” about another 200 bhp to get him there or something because I don’t see it. Just to go over 500 I had to stroke mine to 427 and get my compression near 12:1 N/A. Good luck OP. That costs money. Lots of it.
It’s almost like much of this information is free and even explained on YouTube and this very forum, and even this thread, but yet folks still don’t take the time to research it. They just want it now. If I was less honest I would be one of those tooners you are talking about because some of these folks might actually deserve to be taken to the bank. Call me crazy, but I think I just described a portion of the current tuner market.
Unfortunately this seems to be the trend even now. People are afraid to learn how to tune or learn literally anything about it, so they have no f’n clue what they’re getting. Worse, these same folks get on forums like this and try to sell how great their “experience” was when they have no clue how close their car is to exploding, or how much power they are missing out on because someone tuned their airmass to be 10:1 in PE for “safety.”
The best example perhaps is our glorious OP, who asked a complex question, involving many factors, and has yet to grace us again with his decision. He’s actually thinking he can get 550 whp out of what he has with stated planned mods. He must be assuming someone can “tune in” about another 200 bhp to get him there or something because I don’t see it. Just to go over 500 I had to stroke mine to 427 and get my compression near 12:1 N/A. Good luck OP. That costs money. Lots of it.
It’s almost like much of this information is free and even explained on YouTube and this very forum, and even this thread, but yet folks still don’t take the time to research it. They just want it now. If I was less honest I would be one of those tooners you are talking about because some of these folks might actually deserve to be taken to the bank. Call me crazy, but I think I just described a portion of the current tuner market.
The best example perhaps is our glorious OP, who asked a complex question, involving many factors, and has yet to grace us again with his decision. He’s actually thinking he can get 550 whp out of what he has with stated planned mods. He must be assuming someone can “tune in” about another 200 bhp to get him there or something because I don’t see it. Just to go over 500 I had to stroke mine to 427 and get my compression near 12:1 N/A. Good luck OP. That costs money. Lots of it.
It’s almost like much of this information is free and even explained on YouTube and this very forum, and even this thread, but yet folks still don’t take the time to research it. They just want it now. If I was less honest I would be one of those tooners you are talking about because some of these folks might actually deserve to be taken to the bank. Call me crazy, but I think I just described a portion of the current tuner market.
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Im also not saying everyone needs to learn how to tune, but modifying your car and doing literally zero research into the impact of the parts (after researching the parts) makes no sense to me. You should at least know what you want when you show up for a tune.
I can understand, but on the other hand I’ve also helped a **** ton of folks learn the basics. For that I have zero regrets. If you go to the comments on my videos you’ll see why I’m not upset in the least for taking the time to make those. I’m all about helping people out. I just get a little frustrated at the laziness of others.
Im also not saying everyone needs to learn how to tune, but modifying your car and doing literally zero research into the impact of the parts (after researching the parts) makes no sense to me. You should at least know what you want when you show up for a tune.
Im also not saying everyone needs to learn how to tune, but modifying your car and doing literally zero research into the impact of the parts (after researching the parts) makes no sense to me. You should at least know what you want when you show up for a tune.
Originally Posted by ChopperDoc
Unfortunately this seems to be the trend even now. People are afraid to learn how to tune or learn literally anything about it, so they have no f’n clue what they’re getting. Worse, these same folks get on forums like this and try to sell how great their “experience” was when they have no clue how close their car is to exploding, or how much power they are missing out on because someone tuned their airmass to be 10:1 in PE for “safety.”
The best example perhaps is our glorious OP, who asked a complex question, involving many factors, and has yet to grace us again with his decision. He’s actually thinking he can get 550 whp out of what he has with stated planned mods. He must be assuming someone can “tune in” about another 200 bhp to get him there or something because I don’t see it. Just to go over 500 I had to stroke mine to 427 and get my compression near 12:1 N/A. Good luck OP. That costs money. Lots of it.
It’s almost like much of this information is free and even explained on YouTube and this very forum, and even this thread, but yet folks still don’t take the time to research it. They just want it now. If I was less honest I would be one of those tooners you are talking about because some of these folks might actually deserve to be taken to the bank. Call me crazy, but I think I just described a portion of the current tuner market.
The best example perhaps is our glorious OP, who asked a complex question, involving many factors, and has yet to grace us again with his decision. He’s actually thinking he can get 550 whp out of what he has with stated planned mods. He must be assuming someone can “tune in” about another 200 bhp to get him there or something because I don’t see it. Just to go over 500 I had to stroke mine to 427 and get my compression near 12:1 N/A. Good luck OP. That costs money. Lots of it.
It’s almost like much of this information is free and even explained on YouTube and this very forum, and even this thread, but yet folks still don’t take the time to research it. They just want it now. If I was less honest I would be one of those tooners you are talking about because some of these folks might actually deserve to be taken to the bank. Call me crazy, but I think I just described a portion of the current tuner market.
Ron, I guess you're going to make me open my laptop and check out this problem your having.
I will say we tune opposite of each other. I always, always always tune the VE table first. If the car won't run I just hack on the VE till I can get heading in the right direction. I think it's a quirk of mine because of how mad I was when I found out how garbage my tune looked when this all started in LS stuff.
Probably the best money I spent, honestly, getting screwed by that "tuner"
I will say we tune opposite of each other. I always, always always tune the VE table first. If the car won't run I just hack on the VE till I can get heading in the right direction. I think it's a quirk of mine because of how mad I was when I found out how garbage my tune looked when this all started in LS stuff.
Probably the best money I spent, honestly, getting screwed by that "tuner"
I thought about making a youtube video. Even got about halfway through recording one, going through all the physics of idle control before I decided it was ****
