Help learning to tune - Stock 98 TA with Incon TT kit @ 7-8psi
12-09-2008, 12:04 PM
#21
you need the fuel pressure to rise with boost, otherwise your injectors get smaller when in boost. (current 58 psi rail pressure, 0 psi manifold pressure = 58 pressure delta.
If you do not raise the rail pressure, you now have 58# of rail pressure, and 8 pounds of manifold pressure, resulting in a 50 psi pressure delta. You’ve just taken your 60# injectors and make them flow like 55.71# injectors, or taken your 42# injectors and make them flow like 39# . This is bad, and results in you lying to the pcm to tell it more air is coming into the motor than actual. (all your calculations will be incorrect)
You can get around the maf, but first you must get a maf that supports more than 512 g/second at les than 11250 hz. Then you can rescale several tables in the pcm to make this work correctly. This is something I’ve done 3-4 years ago to prove it can be done on my 98 ws6, but never tested it other than with a stockfish na car.
If you do not raise the rail pressure, you now have 58# of rail pressure, and 8 pounds of manifold pressure, resulting in a 50 psi pressure delta. You’ve just taken your 60# injectors and make them flow like 55.71# injectors, or taken your 42# injectors and make them flow like 39# . This is bad, and results in you lying to the pcm to tell it more air is coming into the motor than actual. (all your calculations will be incorrect)
You can get around the maf, but first you must get a maf that supports more than 512 g/second at les than 11250 hz. Then you can rescale several tables in the pcm to make this work correctly. This is something I’ve done 3-4 years ago to prove it can be done on my 98 ws6, but never tested it other than with a stockfish na car.
12-09-2008, 01:08 PM
#22
Assumeing you were within a safe duty cycle on the injectors... could you change the injector flow rate table to compensate for the "loss" in rail pressure? Or is there a table that you can compensate for injector flow rate based on manifold pressure? Is the inverse true also... that under a condition of vacume that the pressure delta is actually higher than the rail pressure?
12-09-2008, 01:25 PM
#23
no, the pcm only has 80-0 KPA, with 0 being atmosphere for the injector slope function on the 98 pcm, (some newer pcms may be able to compensate for boost, such as the cobalt SS..) The pcm will never know the injectors are getting smaller, when you need them the most.
Ryan
Ryan
12-09-2008, 01:38 PM
#24
Im assuming there is a way around that though? I know the STS kits at least dont come with a regulator or anything.
I guess i would have to "Trick" the computer by telling it that "X" amount of air (read by the MAF) would require more fuel, and increase the difference with air flow (ideally it would be off of manifold pressure but my 98 wont let me) ready by the MAF... since boost=airflow?
I guess i would have to "Trick" the computer by telling it that "X" amount of air (read by the MAF) would require more fuel, and increase the difference with air flow (ideally it would be off of manifold pressure but my 98 wont let me) ready by the MAF... since boost=airflow?
12-09-2008, 01:41 PM
#25
right, you can just lie through the maf values, telling the pcm that more air is coming in than really is, but you end up lying to the pcm (probably 80% of people just do this on entry level boost kits)
(something that I would not do myself, and when I was going to put an incon kit on m 98 ws6, I had purchased 1998 firebird v6 fuel lines, and a 1997 corvette rail with front mount regulator.)
Ryan
(something that I would not do myself, and when I was going to put an incon kit on m 98 ws6, I had purchased 1998 firebird v6 fuel lines, and a 1997 corvette rail with front mount regulator.)
Ryan
12-09-2008, 01:49 PM
#26
Do you feel that doing it that "trick MAF" way would be dangerous at my power levels? I dont want to cut a corner that i shouldn't, but if its possibly to make it work for now then i would like to do it (simply because it will cost no money out of pocket)
Honestly im just trying to get this thing going for now... im not in the position to put much money into it right now, and just want it on there so i can enjoy it untill i can go back and redo things one at a time. A "good" fuel system is next on the list but wont happen till Jan-Fed after the holidays.
Honestly im just trying to get this thing going for now... im not in the position to put much money into it right now, and just want it on there so i can enjoy it untill i can go back and redo things one at a time. A "good" fuel system is next on the list but wont happen till Jan-Fed after the holidays.
01-22-2009, 08:54 PM
#27
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Did you get the secondary computer with the incon system? It controls the fuel and timing at the entire rpm (500 rpm's to 9000rpm's) and boost levels (from 0 to 20 lbs, i believe...i haven't really noticed the upper end, as i've never went over 7.5 lb boost).
-Doug
-Doug
01-23-2009, 07:04 AM
#28
The one thing, Beware of taking advise 100% on forums, there are a lot of people out there that know what they are talking about and a bunch that "Think" they know. Listen to reputable people, Frost, Bob @ EPP and a few others. I read an article on the Nitrous section where a member told one users that he needed the hottest plug to run a 200 shot but just to close the gap, well you know what happened there. Others will say keep adding timing until you "Hear" detonation. On a forced inducted or nitrous motor, this will be the last thing you hear.......
01-24-2009, 04:44 AM
#32
I'm not familiar with efi live, but like others said, they do not support the 2/3 bar setup for 98. I also have a 98, but I have hp tuners. I had the serial version and I'm still waiting for my upgrade to come in so I can get started. By researching about tuning, I've found that the key is logging and transferring the data you find in the logs to the editor.
Also, a big point is having your injector flow rate to match correctly to your information. There are spreadsheets that allow you to enter in your injector information and give you your injector flow rate (IFR) information to input into the editor. A good thing to have is a boost referenced regulator that way you can have the correct fuel pressure at the injectors like also mentioned.
Also, a big point is having your injector flow rate to match correctly to your information. There are spreadsheets that allow you to enter in your injector information and give you your injector flow rate (IFR) information to input into the editor. A good thing to have is a boost referenced regulator that way you can have the correct fuel pressure at the injectors like also mentioned.
01-25-2009, 06:18 PM
#33
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I'm glad this thread came about... looks like some good books I need to pick up. I'm also trying to learn tuning with EFILive and a wideband. I won't be working on a turbo setup luckily, but still learning. After doing some research, I've quickly decided I don't want to deal with trying to tune my old 98 PCM. I picked up a later model PCM on here for a good price, and came across a Word document with what pins go where on the new PCM and an Excel file for cross referencing to make sure you put everything where it belongs. After doing this, it's just a matter of changing some fuel stuff in the PCM to work with the 98 stuff... I'm sure I can dig up the link on here to get you all of this information if it's something you're interested in. I'm halfway through the process of pulling the pins out of my 98 and labeling them. I feel it will definitely be worth it as I'll be able to run a custom OS with the later model PCM, and it'll just be an overall easier experience in learning to tune. Just thought I'd throw that out for an idea to consider before you get too involved. Either way, best of luck, and I hope everything goes well for ya. Keep us posted on how things go.
02-07-2009, 06:59 PM
#34
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I have the first Incon Stage II+, installed by Incon at their shop.
They installed a secondary RaceLogic controller under the hood (i've relocated into the glove compartment) where I can plug my computer into and adjust timing and fuel. I left that computer at work, but i'll get a screenshot of the program on monday and i'll snap a picture of the controller.
Weird you've never heard of it.
-Doug
05-03-2009, 07:37 PM
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This isn't a question that's really easy to answer. You're going to have to do a bunch of searching and reading to get an idea of what to do. Then you're going to be practicing your new skills on something that is not very forgiving. Small mistakes lead to big problems.
A somewhat simplistic way of looking at it is that when there's boost you want more fuel and less timing. Boost requires a richer mixture so where you might tune a NA car for power by setting the AFR at 12.5:1 you'll want 11:1. Guys who are really sure of their tuning may tune a little leaner but you'll be treading on thin ice so keep it rich.
Having EFILive and a WBO2 is a good start. First off, you need to setup the injector offset tables to match your new injectors. Once that is setup, read the VE tuning document on efilive's site and ditch your MAF. Run a SD tune so you can command the AFR you want. I've been running COS3 and SD for a couple or three years now and it is the only way to tune imho.
You're going to find out fast that the MAP sensor runs out of resolution just when you need it most. One way to solve the problem is to run a 2bar MAP and rescale your tables. While this cuts the fueling resolution in half, the OS can handle it properly. The benefit is that you can finely tune under boost. Without a 2bar you have to tune the highest tables to the amount of boost you'll run. Not the best thing...
Skip the manual boost controller and get an e-boost2 (EBC). There is no substitute for one. Manual controllers are unpredictable. Finally, do the tuning on a dyno that can load the engine. It's just insane to try and tune on the street. I did it for a while at 3am on a long stretch of road 30 miles out of town. When you're hitting 155-160 while watching the laptop and looking out for road debris and animals, you start to reconsider your life and how you're living it (hopefully
).
Good luck!
A somewhat simplistic way of looking at it is that when there's boost you want more fuel and less timing. Boost requires a richer mixture so where you might tune a NA car for power by setting the AFR at 12.5:1 you'll want 11:1. Guys who are really sure of their tuning may tune a little leaner but you'll be treading on thin ice so keep it rich.
Having EFILive and a WBO2 is a good start. First off, you need to setup the injector offset tables to match your new injectors. Once that is setup, read the VE tuning document on efilive's site and ditch your MAF. Run a SD tune so you can command the AFR you want. I've been running COS3 and SD for a couple or three years now and it is the only way to tune imho.
You're going to find out fast that the MAP sensor runs out of resolution just when you need it most. One way to solve the problem is to run a 2bar MAP and rescale your tables. While this cuts the fueling resolution in half, the OS can handle it properly. The benefit is that you can finely tune under boost. Without a 2bar you have to tune the highest tables to the amount of boost you'll run. Not the best thing...
Skip the manual boost controller and get an e-boost2 (EBC). There is no substitute for one. Manual controllers are unpredictable. Finally, do the tuning on a dyno that can load the engine. It's just insane to try and tune on the street. I did it for a while at 3am on a long stretch of road 30 miles out of town. When you're hitting 155-160 while watching the laptop and looking out for road debris and animals, you start to reconsider your life and how you're living it (hopefully
).Good luck!
