Going for a re-tune.... (Round #2) Updated 10/28/13
- Thread starter hotaccord243
- Start date
hotaccord243
Well-Known Member
Re: Going for a re-tune....
Trying to keep them coming.
Still awaiting the license tabs to at least be able to drive it around on low boost for fun (Since it's been so long). Everyday I check the mail it's like awaiting a birthday present becuase i'm so anxious to get them.
Trying to keep them coming.
Still awaiting the license tabs to at least be able to drive it around on low boost for fun (Since it's been so long). Everyday I check the mail it's like awaiting a birthday present becuase i'm so anxious to get them.
hotaccord243
Well-Known Member
Re: Going for a re-tune....
Got the license tabs yesterday and put them on. Got the AEM A/F guage installed (which was a PITA running the wires) and running correctly and am now officially driving it.
A few kinks to work out:
-Fuel pump fuse is fussy on when it wants to connect
-Radio fuse is fussy as well
-Turbo downpipe studs need to go in
-Idle is running super rich (10-11) and under normal load lean (15-16), and under full load it is about right (13-14) so i'll have to play with my fuel map a little to get it running better.
-Misfires while under boost.
But in the long run, it's good news that I have it running and driveable, so that's a big head start.
I'll post a photo of the mounted guage when I have a chance.
Got the license tabs yesterday and put them on. Got the AEM A/F guage installed (which was a PITA running the wires) and running correctly and am now officially driving it.
A few kinks to work out:
-Fuel pump fuse is fussy on when it wants to connect
-Radio fuse is fussy as well
-Turbo downpipe studs need to go in
-Idle is running super rich (10-11) and under normal load lean (15-16), and under full load it is about right (13-14) so i'll have to play with my fuel map a little to get it running better.
-Misfires while under boost.
But in the long run, it's good news that I have it running and driveable, so that's a big head start.
I'll post a photo of the mounted guage when I have a chance.
Re: Going for a re-tune....
Under full load (i.e boost) you should be in the range of 11.5-12.5. Closer to 11.5 as the pressure builds. This is at least what you do with gasoline. Forget what the targets are for E85 and other fuels.
How do you tune your fuel map? hybrid boost compensation or cell by cell? I've had very good luck with hybrid boost comp. It's how i tuned my car and chido's car's fuel maps. My cars great and i haven't heard any issues from chido
Under full load (i.e boost) you should be in the range of 11.5-12.5. Closer to 11.5 as the pressure builds. This is at least what you do with gasoline. Forget what the targets are for E85 and other fuels.
How do you tune your fuel map? hybrid boost compensation or cell by cell? I've had very good luck with hybrid boost comp. It's how i tuned my car and chido's car's fuel maps. My cars great and i haven't heard any issues from chido
hotaccord243
Well-Known Member
Re: Going for a re-tune....
Yeah i'm actually pretty close to where I am, I need to lean out the idle slightly, and under full boost i'm slightly lean, so i'll want to richen up it under full boost.
Typically i'll just take a look at the fuel map and adjust it via that. Not necessarily cell by cell (although sometimes I do it that way) but more taking areas on the graph and increase/decrase by percentage or number. I find that to be the easiest....
Under full load (i.e boost) you should be in the range of 11.5-12.5. Closer to 11.5 as the pressure builds. This is at least what you do with gasoline. Forget what the targets are for E85 and other fuels.
How do you tune your fuel map? hybrid boost compensation or cell by cell? I've had very good luck with hybrid boost comp. It's how i tuned my car and chido's car's fuel maps. My cars great and i haven't heard any issues from chido
Yeah i'm actually pretty close to where I am, I need to lean out the idle slightly, and under full boost i'm slightly lean, so i'll want to richen up it under full boost.
Typically i'll just take a look at the fuel map and adjust it via that. Not necessarily cell by cell (although sometimes I do it that way) but more taking areas on the graph and increase/decrase by percentage or number. I find that to be the easiest....
Russianred
Snail Spools You!
Re: Going for a re-tune....
Do you just guesstimate where the transition is going to be? On what basis do you select an area/interval to increase/decrease? Or is the key to have a good starting point then smoothen it out as much as possible until the end of the map?
Also Alex, - interested in this hybrid boost comp of which you speak.
Do you just guesstimate where the transition is going to be? On what basis do you select an area/interval to increase/decrease? Or is the key to have a good starting point then smoothen it out as much as possible until the end of the map?
Also Alex, - interested in this hybrid boost comp of which you speak.
Re: Going for a re-tune....
Tuning fuel is easy with a wideband and some data logging. You can do it by using simple math. ((logged afr)/(target afr)) * (injector pulse width). This is all assuming that the measurement and the data come from the same points in the map.
Let's say at 5000 rpms and 100 kpa you have a pulse width of 8.78.
Looking at the data log you see that your afr at that point is 15.5.
That's slightly lean seeing as you are on the dot at atmospheric pressure.
Let's say you wanna run like 14.2, slightly richer than the 14.7 stoichiometric ratio.
So the equation would get set up as follows: (15.5/14.2) * 8.78 = 9.6
So in your fuel map you would put 9.6 where u had 8.78 and your afr should be right on 14.2
Tuning fuel is easy with a wideband and some data logging. You can do it by using simple math. ((logged afr)/(target afr)) * (injector pulse width). This is all assuming that the measurement and the data come from the same points in the map.
Let's say at 5000 rpms and 100 kpa you have a pulse width of 8.78.
Looking at the data log you see that your afr at that point is 15.5.
That's slightly lean seeing as you are on the dot at atmospheric pressure.
Let's say you wanna run like 14.2, slightly richer than the 14.7 stoichiometric ratio.
So the equation would get set up as follows: (15.5/14.2) * 8.78 = 9.6
So in your fuel map you would put 9.6 where u had 8.78 and your afr should be right on 14.2
Re: Going for a re-tune....
Hybrid boost comp is where you tune the motor by having the same injector pulse for all the cells above 100kpa (or atmospheric pressure). Then in a separate table (boost fuel correct table in AEM), you do corrections on those static values. The corrections are pretty straight forward. For every addition 100 kpa of pressure, you add 100% fuel. So let's say you are running the car up to 178 kpa (effectively 11psi of boost which is the max for the stock accord map sensor), you would add 78% more fuel at 178 kpa. Here is a pic of an old map i was running. Hope that explains hybrid boost comp mapping.
Full boost comp mapping is similar, except you make the whole column the same value (usually use 100kpa as the static number). And then you create another correction parameter through the use of throttle injection correction. Then you pull fuel at low throttle percentages and after around 30% throttle (or when ever you are able to make boost given a high enough rpm) you zero out the correction for the throttle and let the boost correction table do the rest.
I have tuned fuel maps using both these methods and prefer hyrbid boost comp tuning for the reason that it is far easier and gives you great drivability.
Hybrid boost comp is where you tune the motor by having the same injector pulse for all the cells above 100kpa (or atmospheric pressure). Then in a separate table (boost fuel correct table in AEM), you do corrections on those static values. The corrections are pretty straight forward. For every addition 100 kpa of pressure, you add 100% fuel. So let's say you are running the car up to 178 kpa (effectively 11psi of boost which is the max for the stock accord map sensor), you would add 78% more fuel at 178 kpa. Here is a pic of an old map i was running. Hope that explains hybrid boost comp mapping.
Full boost comp mapping is similar, except you make the whole column the same value (usually use 100kpa as the static number). And then you create another correction parameter through the use of throttle injection correction. Then you pull fuel at low throttle percentages and after around 30% throttle (or when ever you are able to make boost given a high enough rpm) you zero out the correction for the throttle and let the boost correction table do the rest.
I have tuned fuel maps using both these methods and prefer hyrbid boost comp tuning for the reason that it is far easier and gives you great drivability.
x5carl3tMurd3rx
Well-Known Member
Re: Going for a re-tune....
lots of good info guys keep it up!
lots of good info guys keep it up!
hotaccord243
Well-Known Member
Re: Going for a re-tune....
Yeah I have heard of doing the hybrid fuel control tuning as well. It's pretty basic and by far the easiest way to tune fuel.
I have been driving around and since the a/f is just a hare off of where I would like it to be i will most likely be doing cell by cell. Basically using logging, math, and so forth to figure out exactly where i want it to be.
Last night, I replaced the bolts with studs on the manifold to Turbo connection (10x1.25) and as well as the five bolt downpipe connection (8x1.25). Had to re-tap everythread to clean everything up and get everything straight. However, in the process, I screwed up one stud and couldn't tighten up 1/5. Gotta go get one last stud and then i'll be done with that.
Ill post some photos of the a/f and the stud work as of today this afternoon.
Some other items that will need to be done:
- I need a new starter (if anyone has one let me know)
- Slight misfire under hard boost that I have to fix Prob start with spark plugs.
- I noticed that on the exhaust there is a massive dent in it preventing some major exhaust flow. (i'll have to cut that out and replace it).
- Alignment is needed.
- Fuel map/drivability tune prior to tune for more power.
Other than that I think I should be all good
Yeah I have heard of doing the hybrid fuel control tuning as well. It's pretty basic and by far the easiest way to tune fuel.
I have been driving around and since the a/f is just a hare off of where I would like it to be i will most likely be doing cell by cell. Basically using logging, math, and so forth to figure out exactly where i want it to be.
Last night, I replaced the bolts with studs on the manifold to Turbo connection (10x1.25) and as well as the five bolt downpipe connection (8x1.25). Had to re-tap everythread to clean everything up and get everything straight. However, in the process, I screwed up one stud and couldn't tighten up 1/5. Gotta go get one last stud and then i'll be done with that.
Ill post some photos of the a/f and the stud work as of today this afternoon.
Some other items that will need to be done:
- I need a new starter (if anyone has one let me know)
- Slight misfire under hard boost that I have to fix Prob start with spark plugs.
- I noticed that on the exhaust there is a massive dent in it preventing some major exhaust flow. (i'll have to cut that out and replace it).
- Alignment is needed.
- Fuel map/drivability tune prior to tune for more power.
Other than that I think I should be all good
