Mass air flow and V.E. tuning advise needed
Thread Starter
On The Tree
Joined: Mar 2010
Posts: 112
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From: Iowa
Mass air flow and V.E. tuning advise needed Hey all, I have a 99 z with a 6 speed that I installed headers, ory, and catback on. I purchased hp tuners awhile back and an lc-1 wide band. I turned off the rear o2 sensors and turned off the skip shift for the trans. That stuff was pretty easy. I did a lot of reading awhile back and tried to tune the v.e. by driving on the street. My error was getting better and better but it was taking a long time to get it ideal. I had almost all the cells with in 0-2 but had a few that were still around 5-6. This was by following the stickys on hp tuners website and off of a couple of good books I bought. Anyway this was taking a better part of the week to get that far. Then my clutch master started acting up. So I decided to reload the stock tune till I had more time to deal with it. Plus I never got to the maf tuning.
So now I have some time to play with it again but should it take this long to get it dialed in? Or am I just being to picky with the few cells that are higher?
Also, when and if I do get this part of it down, what do I need to do for wide open tuning? The stuff I remember reading on hp tuners covered only up to 4000 rpm.
So now I have some time to play with it again but should it take this long to get it dialed in? Or am I just being to picky with the few cells that are higher?
Also, when and if I do get this part of it down, what do I need to do for wide open tuning? The stuff I remember reading on hp tuners covered only up to 4000 rpm.
To get it really close, it might take a bit. And picky is good. I'm not sure what sticky you read, but if it said it only went to 4000 rpm, thats just the point where they said you should begin calibrating the MAF because the default setting switches to MAF at 4k. If you really want to be picky (like I am), you'll want to disable the MAF to calibrate the entire VE table, and then run MAF only to calibrate the MAF. This way you can isolate and calibrate them separately.
Thread Starter
On The Tree
Joined: Mar 2010
Posts: 112
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From: Iowa
Well the sticky I read said to just run it up to 4000 rpm. Either it didn't say why or I just missed it. So I take it the maf sensor does all the adjustment past 4k correct? And if I wanna adjust the ve any farther up the rpm range thats fine too right? Although that might be tricky to do on the street.
O.k. so what about wide open throttle? Do I just set p.e. to command like 12.7-13.2 afr and check it against the wideband?
O.k. so what about wide open throttle? Do I just set p.e. to command like 12.7-13.2 afr and check it against the wideband?
Well the sticky I read said to just run it up to 4000 rpm. Either it didn't say why or I just missed it. So I take it the maf sensor does all the adjustment past 4k correct? And if I wanna adjust the ve any farther up the rpm range thats fine too right? Although that might be tricky to do on the street.
O.k. so what about wide open throttle? Do I just set p.e. to command like 12.7-13.2 afr and check it against the wideband?
O.k. so what about wide open throttle? Do I just set p.e. to command like 12.7-13.2 afr and check it against the wideband?
After you tuned the MAF table, command the PE to what AFR you want @ WOT. Be it 12.6-12.7 or 12.9-13.0 AFR or make it rich 12.6-12.7 at 4K-5K rpm then raise it to 12.8-12.9 from 5K to where ever you peak power is set at.
To get that commanded PE to be actual AFR reading, adjust your MAF table.
12 Second Club
Joined: Dec 2008
Posts: 281
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From: A small town, MS
Why not disable MAF, then set your PE values to make your AFR at WOT what you want it, then tune the VE all the way to 6500 or whatever you want to revv your engine to? Then reinable the MAF and tune it so that AFR matches the commanded value with the MAF turned on? That way you get a SD+MAF tune that will be right with or without the MAF. That's how I was taught to do it. Works well in every car I've messed with.
You can do it that way but if you're still using the MAF it's not neccesary; SD it is. MAF car i usually go up to around 4200 on the VE table then trend the rest of the way up. Then I tune my MAF in the lower regions. The correction tends to stay close across the boards. If i tune the MAF up to 6000hz and see a correction of 10%, i'll add that plus 5% to stay safe then do my WOT tuning
Set your hit filter a little higher on your datalogger and it should bring those 5-6% areas a little closer to reality. The longer you drive on a scan the more accurate the information will be.
Also take note of what the VE model looks like. If you have any odd spikes you can hand smooth them. Use common sense. If you make a correction on the 2500 rpm column and you see you ve numbers not trending then make a correction there
IE.
kpa - 2500
30 - 52
35 - 53
40 - 68 <-- out of place
45 - 55
50 - 56
Set your hit filter a little higher on your datalogger and it should bring those 5-6% areas a little closer to reality. The longer you drive on a scan the more accurate the information will be.
Also take note of what the VE model looks like. If you have any odd spikes you can hand smooth them. Use common sense. If you make a correction on the 2500 rpm column and you see you ve numbers not trending then make a correction there
IE.
kpa - 2500
30 - 52
35 - 53
40 - 68 <-- out of place
45 - 55
50 - 56
Thread Starter
On The Tree
Joined: Mar 2010
Posts: 112
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From: Iowa
O.k. sounds like I was on the right track. It was takin so long I was thinkin I must be missing something. Its supposed to be a nice weekend comin up. I'll see If I can squeeze in some tuning time.
Thanks for the quick replys.
Thanks for the quick replys.
