beginning tune on big cam

[mdj]

while waiting on on burn2 from moats I have been looking at tables on tuner pro.what would be first line of attack to bring idle under controle from big cam,as in what tables to look at first.(.500 lift,218/228 dur. at .050,112 ls).I am still not clear on relation of blm count and ve table and what to change to bring the blm to 128 target.

EDIT: Went thru tutorial many times,have a 7747 ecm and have loaded the 7747 v5 xdf and the 7747v5 adf

[EagleMark]

Did you get the 27Fs512 chips and a G2 adapter to solder in the ECM as well?

Here's a thread you should read that will help a lot with working VE tables.
http://www.gearhead-efi.com/Fuel-Inj...4-7747-ve1-ve2

Dave W VE Fixer spreadsheet.
http://www.gearhead-efi.com/Fuel-Inj...r-Spread-Sheet

You can use the bin and XDL data log from the tutorial to learn the spreadsheet.

[gregs78cam]

That cam is not too much bigger than mine. To get the idle inline, I would lock it in Open Loop and tweak the 6 or 9 VE and spark cells right around where it idles until you get it right. That is what I did, a Wideband is very helpful with that, but a Narrowband should work OK, just shoot for a steady-ish 0.450 V from the O2.

[EagleMark]

A BLM above 128 indicates a long term lean condition, the ECM is adding fuel over the base calibration. A BLM below 128 indicates a long term rich condition, the ECM is removing fuel from the base calibration.
The idea is to change the VE tables to get the BLM as close to or just below 128 as possible. If your BLM's over the entire range are high or low, you should probably address that first.
High BLM (using a BLM of 140 and VE table value of 65 as an example):
1. Divide the BLM value by 128, result 1.09
2. Multiply the BLM value at that RPM/kpa point by 1.09 ; (65 * 1.09) = 71.09
3. Enter that new value in the table.
Low BLM (using a BLM of 110 and VE table value of 65 as an example):
1. Divide the BLM value by 128, result 1.16
2. Divide the BLM value at that RPM/kpa point by 1.16 ; (65 / 1.16) = 56.03
3. Enter that new value in the table.

[mdj]

are you getting the blm from the blm history table then(most recent,history average,running average,etc.)The ve table is rpm and I think map readings(20,30,40,50,etc.)?can you pull up both tables at same time on one sceen(blm history and ve table).I have tried to pull up ve table correction spreadsheet but it comes up trying to get me to buy "microsoft office" and "openoffice" wont load any sugestions?

[EagleMark]

Open Office is a big download and free and works for me.

BLM History Average is what I use from TP Data. Make sure there is a large sample count, don't want to use 1 sample the is high or low. Only copy to 3200 RPM because that is all that is in the VE table. The BLM history table goes higher for testing.

BLM History table or any table in TunerPro can click on blank box top left and highlight entire table. Or click top left cell and hold down Shift key and click on 3200 RPM 100 MAP for cells you need to match VE table and spreadsheet.
Learn to copy and paste with keys.
Copy Ctrl + C
Paste Ctrl + V

[mdj]

ok mark,was not giving openoffice enough time.got it now,however when opening the ve correction with openoffice spreadsheet it says file is corrupt and can not open.I loaded it from a thread you posted that directed me to a differerent thread,is there some where else I could download it from.appears to be a gret tool for starting out on the ve tables.

[EagleMark]

Some times re starting a computer helps after install. What windows do you have? You were also new to PC and tuning right? I forget...

I just checked the link and downloaded the file, UN ZIPPED it, clicked on it and because of my security software there was a warning of unpublished? Since I knew it was safe I OKed.

But with Open Office in a Windows PC and an Excel file it will always look for Excell. Right click on the file, Properties, second box down File Type and Opens With, Open with Open Office. Should get the file assiciations in order.

You do need to learn this. Also need to work on your bin before even datalogging!

[mdj]

That cam is not too much bigger than mine. To get the idle inline, I would lock it in Open Loop and tweak the 6 or 9 VE and spark cells right around where it idles until you get it right. That is what I did, a Wideband is very helpful with that, but a Narrowband should work OK, just shoot for a steady-ish 0.450 V from the O2.

How do you lock into open loop and what are you refering to with the 6 or 9 in VE and spark cells .Is the 6 or 9 a position on the tables or the tables themselves?also not sure how to add VE(fl2)to VE(fl1) so that I can zero out VE(fl1) tables.Or with a modified engine should I even do that.Just burned first chip lookng foward to trying in the morning.

[gregs78cam]

Raise your Closed loop enable temp to 150C. Then as you are looking at your VE and Spark tables your vehicle should idle in a cell or two around 800RPM and 35-50Kpa. So make the 400, 800, 1200 and 35-50Kpa all the same number and adjust that number until you get a good stable idle at the appropriate speed for your cam, as close to stoich as possible. I say that last part as some engines will not at all like to idle well at what appears to be stoich. As far as adding VE1 and VE2, I have not had to do that with any of mine as I have '7427s, but I think it is as simple as just adding the single column values to each column of the main table.

[EagleMark]

http://www.gearhead-efi.com/Fuel-Inj...4-7747-ve1-ve2

[EagleMark]

Because your starting from scratch with a built engine we started a new thread with things we do to stock bins for modified engines. Just for pointers.

http://www.gearhead-efi.com/Fuel-Inj...odified-engine

[mdj]

well started burning chips and trying to lean out this idle changing the VE all the way did not do it,tryed about 20 combinations then the chip died.Now Im dead in the water till new chips get here.Ive got a decent idle and have not started on tweeking SA.but by looking at o2 readings its very rich,staying in the 800 and 900 range somtimes kicking out a 02 rich code.going to go over mechanics again(plugs,wires,vacume leak,etc.)

[EagleMark]

Always good to have mechanicals checked!

Did you raise the idle? About 800 warmed up.

Did you add some spark advance? About 5 degrees at idle to start.

Both of those will help idle with that cam. Judge it only when fully warmed up and even then rev the motor and let idle. Remember it's a wet intake manifold.

Play back your log or enable the Data Tracing feature of the XDF and ADX files, you will see exactly where your fuel and spark are at idle. Look at the link below, I've already done all the work in those files but it will show you how to use the feature.
http://www.gearhead-efi.com/Fuel-Inj...unerPro-How-To

[mdj]

Got datatracing going on VE table,but why does idle jump all around on the VE table even though idle rpm is fairly consistent.


That was pretty dang good directions Mark,I have no idea what I have done but the data tracing worked.


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