Scary VE area
11-28-2006, 08:55 PM
#51
Originally Posted by foff667
would you mind posting a screenshot of your VE tables steps? do you guys have a boost enrichement table?
No boost enrichment, but we have the same functionality. Commanded Loop AFR table is modified to have RPM and MAP instead of ECT and MAP. As such, PE is no longer needed, and subsequently can be enabled above 105kPa as needed.
11-28-2006, 08:58 PM
#52
alright...my opinion....blah. Big whoop. I wouldn't worry about this. WHO would ever get in those cells with 30% to 40%TPS and 1st gear? Those cells in ANY other driving scenario besides what you are doing would be decel. Although, I am impressed, I have never been that far over there (there=lowkpa/highrpm) with any kind of throttle...really never had enough *****. LOL
Hey appreciate yours and all other comments. I think you have more of an understanding to this than you give yourself credit. At least you can relate to a blown truck. Modest me thinks.
Engine sounds great winding up. I love it.
I'd of had it all the way to 6200 if hadn't started seeing the lean. Not ***** its faith in the SBC. Sounds a lot better than the BB Pontiac I used to take to that RPM. Was the first time I've ever felt a surge I hear some talking about. I agree WHO would ever be in those areas. I am not worried about it really, but I will get it closer and has made for an interesting discussion. It will not be fine tuned regardless whats the harm?
Keep in mind, (getting ready to speak out of my ***, correct me if i am wrong) 33kpa=hardly any cylinder pressure, or hardly any to scare you with a lean afr. Again, when are you gonna be over there in 1st gear. I'd tune those cells for when I'd normally be in those cells. This is just a note, you ARE at 4800 rpm, that is pretty high for a 18:1afr.
You are telling me I probably shouldn't be scared then at the end you are reminding me that I am 18:1 AFR. Which is it? Hmmm tune it for normal driving... that would be easy. Leave it alone. Probably see it normally after a 140mph blast and coast it out. Then DFCO will be on and I'd be at over 22:1 AFR. I THINK I should just tune it to what it wants under the conditions I am seeing it. Not that I would normally ever go there but who knows, out partying one night, throw it in 1st accidentally, crank the stereo, have the dash lights out or can see them... crap happens. 
on another side note, i've been helping a few others with 2bar tuning on '03 and up trucks over email and that 10kpa crap really bothers me. Well, this weekend i hooked up (yeh he was a good lay) with holty to screw around with part maf/part sd and that 10kpa crap showed just how crappy it is on at least a stock cam. So many times you will be making adjustments as per 25+kpa scenarios and then you'll be dealing with 12kpa decels. Well all of those are 30kpa on your '03+ ve table.
Yeh so let off the gas at 2000rpm and 70mph(25kpa) and you get a nice lean decel, but off the gas at 2000 rpm and 50mph(12kpa) and you get a rich decel.
Had started to get a feel for it. I recognize the trends you mention weird lean and rich spikes. Think the key is to move the pedal a slowly as possible.
My opinion roger tune your ve in 1/4's. Tune 400-1600 rpm and 30-70kpa for example. It will help you tune the way you'll more than likely drive everyday. I don't do 1/4's, I drive the **** out of it, about an hour of loggin, all ways, slow smooth throttle transitions. Keep in mind without that maf what you SHOULD see is lean tip in and rich spike leaving the throttle. Should...should. LOL I said should right? Don't let anybody fool ya, it's hard, 2bar tuning IMO, there are so many variables and things that can screw with ya. Keep at it.
I think I'll find some sort of sense in how to approach it. Just putting it in cruise on relatively flat stretches of interstate and varying speed very gingerly, in 3rd and OD will go a long way. I'm committed now. I will get it done. May take me a year. What will suck is that if I get this done and spend all this time and money on it and don't realize any gains from it. IE, better fuel mileage, improved drivability, throttle response and most important better ET's
Thanks so much for your help
Hey appreciate yours and all other comments. I think you have more of an understanding to this than you give yourself credit. At least you can relate to a blown truck. Modest me thinks.
Engine sounds great winding up. I love it.
I'd of had it all the way to 6200 if hadn't started seeing the lean. Not ***** its faith in the SBC. Sounds a lot better than the BB Pontiac I used to take to that RPM. Was the first time I've ever felt a surge I hear some talking about. I agree WHO would ever be in those areas. I am not worried about it really, but I will get it closer and has made for an interesting discussion. It will not be fine tuned regardless whats the harm? Keep in mind, (getting ready to speak out of my ***, correct me if i am wrong) 33kpa=hardly any cylinder pressure, or hardly any to scare you with a lean afr. Again, when are you gonna be over there in 1st gear. I'd tune those cells for when I'd normally be in those cells. This is just a note, you ARE at 4800 rpm, that is pretty high for a 18:1afr.
You are telling me I probably shouldn't be scared then at the end you are reminding me that I am 18:1 AFR. Which is it?
Hmmm tune it for normal driving... that would be easy. Leave it alone. Probably see it normally after a 140mph blast and coast it out. Then DFCO will be on and I'd be at over 22:1 AFR. I THINK I should just tune it to what it wants under the conditions I am seeing it. Not that I would normally ever go there but who knows, out partying one night, throw it in 1st accidentally, crank the stereo, have the dash lights out or can see them... crap happens. on another side note, i've been helping a few others with 2bar tuning on '03 and up trucks over email and that 10kpa crap really bothers me. Well, this weekend i hooked up (yeh he was a good lay) with holty to screw around with part maf/part sd and that 10kpa crap showed just how crappy it is on at least a stock cam. So many times you will be making adjustments as per 25+kpa scenarios and then you'll be dealing with 12kpa decels. Well all of those are 30kpa on your '03+ ve table.
Yeh so let off the gas at 2000rpm and 70mph(25kpa) and you get a nice lean decel, but off the gas at 2000 rpm and 50mph(12kpa) and you get a rich decel.Had started to get a feel for it. I recognize the trends you mention weird lean and rich spikes. Think the key is to move the pedal a slowly as possible.
My opinion roger tune your ve in 1/4's. Tune 400-1600 rpm and 30-70kpa for example. It will help you tune the way you'll more than likely drive everyday. I don't do 1/4's, I drive the **** out of it, about an hour of loggin, all ways, slow smooth throttle transitions. Keep in mind without that maf what you SHOULD see is lean tip in and rich spike leaving the throttle. Should...should. LOL I said should right?
Don't let anybody fool ya, it's hard, 2bar tuning IMO, there are so many variables and things that can screw with ya. Keep at it.I think I'll find some sort of sense in how to approach it. Just putting it in cruise on relatively flat stretches of interstate and varying speed very gingerly, in 3rd and OD will go a long way. I'm committed now. I will get it done. May take me a year. What will suck is that if I get this done and spend all this time and money on it and don't realize any gains from it. IE, better fuel mileage, improved drivability, throttle response and most important better ET's
Thanks so much for your help
11-28-2006, 09:11 PM
#53
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Originally Posted by dc_justin
15-105kPa VE table is stock with a custom OS, 5kPa increments. Additional VE table is in 10kPa increments from 105kPa to 285kPa.
No boost enrichment, but we have the same functionality. Commanded Loop AFR table is modified to have RPM and MAP instead of ECT and MAP. As such, PE is no longer needed, and subsequently can be enabled above 105kPa as needed.
No boost enrichment, but we have the same functionality. Commanded Loop AFR table is modified to have RPM and MAP instead of ECT and MAP. As such, PE is no longer needed, and subsequently can be enabled above 105kPa as needed.
I will definitly mention it to them to see what they can do though about at least the fact that it doesnt extend down far enough, not sure what they'll be able to do if anything though
11-28-2006, 09:34 PM
#54
Originally Posted by 03sierraslt
Ky- I replied to your thread about 2bar in HPT forums, couple questions about your tune...
11-29-2006, 07:05 AM
#55
Originally Posted by KySilverado
You are telling me I probably shouldn't be scared then at the end you are reminding me that I am 18:1 AFR. Which is it?
HAHA...it's my inability to make up my mind showing there. I was just thinking out loud...you know..."hmmm it is a real lean number..." But I stick to my first statement. Ahhh, leave it alone. Tune those cells for when you would actually be in them.
***********************************
Hmmm tune it for normal driving... that would be easy. Leave it alone. Probably see it normally after a 140mph blast and coast it out. Then DFCO will be on and I'd be at over 22:1 AFR. I THINK I should just tune it to what it wants under the conditions I am seeing it. Not that I would normally ever go there but who knows, out partying one night, throw it in 1st accidentally, crank the stereo, have the dash lights out or can see them... crap happens. LOL I guess crap does happen, I'd bet you'd hit the rev limiter in that situation though.
**********************************
Had started to get a feel for it. I recognize the trends you mention weird lean and rich spikes. Think the key is to move the pedal a slowly as possible.
It is the key if you are determined to get the MAF back to operating in your 2bar tune someway, but if not, you are gonna have to find a nice middle road for that "throttle blip", the quick burst if TPS%. Depending on your cam, pulley size, and such things that determine just how fast your MAP rate is you'll definitely notice a "fattening" of cells going into PE to help curve the huge lean spike you'll get due to no MAF. MAP sensor can only count for air that is IN the manifold, not the air that is "coming". That creates a delay in fueling needs.
In the same sentence, on the highway and you press the gas to get you going just a little bit and you slide into boost at 2000rpm-you'll go rich cuz you have tuned the lean tip in cuz of quick throttle transition. In my tune, I went with richen the tip in and adjusting shift/tcc tables to help keep me out of those areas on the highway.
******************************
I think I'll find some sort of sense in how to approach it. Just putting it in cruise on relatively flat stretches of interstate and varying speed very gingerly, in 3rd and OD will go a long way. I'm committed now. I will get it done. May take me a year. What will suck is that if I get this done and spend all this time and money on it and don't realize any gains from it. IE, better fuel mileage, improved drivability, throttle response and most important better ET's
Thanks so much for your help
IMO, better ET's aren't gonna come at you going 2bar. Better economy can, especially since you have the ability to go OL and can lean it out. The BIGGEST plus to 2bar is the whole design of it, your MAF can only read so far on the airflow. You are maxing it. When it fails, where is your fueling(air) coming from? Well if you aren't 2bar, the calcs are your 105kpa row in your ve table. That can be a yikes, but most have that line rich enough to cover them. But is that efficent? no? Safe? hell no! I haven't heard of going 2bar making people faster, just more efficient in air calcs and better driveability. I guess it can make you go faster if you were in fact failing your maf in 1bar and your 105kpa row before was shitty.
HAHA...it's my inability to make up my mind showing there. I was just thinking out loud...you know..."hmmm it is a real lean number..." But I stick to my first statement. Ahhh, leave it alone. Tune those cells for when you would actually be in them.
***********************************
Hmmm tune it for normal driving... that would be easy. Leave it alone. Probably see it normally after a 140mph blast and coast it out. Then DFCO will be on and I'd be at over 22:1 AFR. I THINK I should just tune it to what it wants under the conditions I am seeing it. Not that I would normally ever go there but who knows, out partying one night, throw it in 1st accidentally, crank the stereo, have the dash lights out or can see them... crap happens.
LOL I guess crap does happen, I'd bet you'd hit the rev limiter in that situation though. **********************************
Had started to get a feel for it. I recognize the trends you mention weird lean and rich spikes. Think the key is to move the pedal a slowly as possible.
It is the key if you are determined to get the MAF back to operating in your 2bar tune someway, but if not, you are gonna have to find a nice middle road for that "throttle blip", the quick burst if TPS%. Depending on your cam, pulley size, and such things that determine just how fast your MAP rate is you'll definitely notice a "fattening" of cells going into PE to help curve the huge lean spike you'll get due to no MAF. MAP sensor can only count for air that is IN the manifold, not the air that is "coming". That creates a delay in fueling needs.
In the same sentence, on the highway and you press the gas to get you going just a little bit and you slide into boost at 2000rpm-you'll go rich cuz you have tuned the lean tip in cuz of quick throttle transition. In my tune, I went with richen the tip in and adjusting shift/tcc tables to help keep me out of those areas on the highway.
******************************
I think I'll find some sort of sense in how to approach it. Just putting it in cruise on relatively flat stretches of interstate and varying speed very gingerly, in 3rd and OD will go a long way. I'm committed now. I will get it done. May take me a year. What will suck is that if I get this done and spend all this time and money on it and don't realize any gains from it. IE, better fuel mileage, improved drivability, throttle response and most important better ET's
Thanks so much for your help
IMO, better ET's aren't gonna come at you going 2bar. Better economy can, especially since you have the ability to go OL and can lean it out. The BIGGEST plus to 2bar is the whole design of it, your MAF can only read so far on the airflow. You are maxing it. When it fails, where is your fueling(air) coming from? Well if you aren't 2bar, the calcs are your 105kpa row in your ve table. That can be a yikes, but most have that line rich enough to cover them. But is that efficent? no? Safe? hell no! I haven't heard of going 2bar making people faster, just more efficient in air calcs and better driveability. I guess it can make you go faster if you were in fact failing your maf in 1bar and your 105kpa row before was shitty.
11-29-2006, 07:10 AM
#56
Originally Posted by foff667
I agree 100%, but its the room gm gave them to work with unfortunatly.
I know I know, I can't help myself for bashing this. I think this is the reason that efi has 5kpa resoltion on the non-boost table. They don't have a be table, and kept the resolution on the non-boost table. 10 kpa on boost. Just a different way to skin a cat, I just wonder how much the lower resolution is hurting our tuning capability in the non-boost area. I don't wonder actually, I know it is hurting some.
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