Using BLM / 128 X Current VE to adjust the main fuel table is simple enough, I think. But how do you calculate the adjustment necessary for the second VE table with no MAP in the VE table?

 

bump.

 

Table #2 is an adder to table #1. So lets say you have a BLM read at 3200 rpms 50 MAP of 135. I believe the RPM value in table 2 at 3200 is then added to the highest RPM(2800?) in table one at the same MAP(50). So if you have a BLM of 135 at 3200 rpms then 135/128 multiply times the value in table #2 to give you total fuel the engine sees. I have not used that concept for quite a while so I hope the info I provided is accuarate! I use EBL that has expanded fuel tables for higher RPM with MAP up to 6000 rpms.

 

Okay, so when using BLM / 128 X CURRENT VE you always use the total of a cell(RPM) on both VE tables.

Using the example of a 110 BLM, where VE 1 shows 20% and VE 2 is 50%, and the total VE after calculation is 60.2 (110/128= 0.86
0.86*70%= 60.2), HOW do you allocate the right amount to the appropriate VE table?? I mean, how much of the 60.2 in the case of this hypothetical example goes into VE table ONE and how much into VE table TWO.??

Thanks!

Whats EBL??

 

EBL= dynamicefi.com

I dont recall changing both tables. For instance lets say the lower table #1 max RPM shows at 2800 or 2400 I forget. You are attempting to change 3200 50 map after a datalog. I dont believe you touch 2400-2800 50 map table #1 as if you do it wont be right for 2800 50 map when running at that point in table. The stock 7747 tables are pretty course so resolution is not that good. GM saw a need to provide for higher RPM tables but capped it I recall around 4400rpms. Being an adder table allowed more fuel above 2400-2800 when in CL.

 

I think I posted misinfo! Kind of. I have not looked at a mask the add on table(VE2) for quite a while so forgive me. On the way home last night I recollect that my first attempt at tuning DID require me to modify both VE1 and VE2 tables. That is because VE2 I believe goes from 400 up to 4400 or so on RPM. so yes you need to multiply VE% in both. I thought for a while the VE2 started at 2200 and went to 4400. that is how my current VE2 works cept it goes to 6000(EBL). It is not an adder. so what I did was to take 800-2000(whatever it is in VE2) and move those values into VE1 and zero out that area of VE2. IOW if 1600 rpm in VE2 was say value 20 I placed that value in VE1 at 1600 accross the board on MAP. Same on 2000 in VE2 and so forth. I recall not adding in VE2 at 400 rpms as was instructed not to do so? No change on that one. So for a BLM at 2800 rpms I only needed to work with the VE2 at 2800 and at 1600 I only need to work with VE1. Made it easier to do a change in table. Hope this is understood.

 

Okay, please correct me where necessary.

1. I take the values from 800 RPM - 3200 RPM in VE2 and copy those values to the appropriate RPM cells across the MAP in VE 1. Then, Zero out ALL cells in VE2, that were copied to VE1.
2. And to make certain I understand this, DON'T copy the VE2 value @ 400 RPM into the 400 RPM cells on VE1??

EDIT: If you do leave the 400 RPM cells unchanged in VE1, do you zero out the 400 RPM value in VE2??

 

1. and 2. are correct. If you get a BLM that you want to change in 400 RPMs then you need to change both VE1 and VE2. I cant recall if I ever say BLM captured at 400. My car will die or pick up on stall saver if it gets to 400RPMS! For me anyway.

Are you running a 7747 with $42? I dont recall the VE1 going to 3200 RPMs as you state? As I said I have not looked at that $42 VE1 table for a long time.

I would do a datalog right before you make the change to zeros and then change bins and see what the result is. I would hope it is the same.

After you get familiar with your tune take a look at dynamicefi.com and note the enhancements. Quite an improvement!

 

I'm using the 7747 ECM with a $42 code mask. The RPM value in VE1 goes up to 3200RPM..

You think the result from transferring the values then zeroing out VE2 would be similar to before the 'zeroing'?

Thanks again.

 

I would think so. Just an interesting test.

 

Update

First, I used a bin which had the values copied directly from VE2 to VE1, and the values which were copied in VE2 ZEROED. The value in VE2 from 800RPM -- 3200RPM was 39.06 in EVERY RPM. With that bin, the truck started but idled up and down, nearly dieing every time it would idle waaay down..

After this, I decided to try an experiment; I opened the original 'base' bin and opened VE1 and VE2. I then added the value of 39.06 (the value in VE2 from 800-RPM to 3200RPM) to the already existing value in each cell of VE1. I then took the total VE% and dumped that number into VE1 from 800-3200RPM. Finally, I zeroed out every value in VE2 from 800-3200RPM that I had previously added to the already existing values in VE1.

It runs now. So if all is well in my bin, do you think I should now be able to adjust VE's between 800-3200RPM using only VE1?

Thankyou

 

So 3600 on up still have the 39.02. I believe that accurrate.

I just remembered I did it the way you stated you just did and then a post was made by Grumpy(RIP) a few days later suggesting that those VE2 800-3200 tables would be better served with a value of 5 in each. I dont think he explained why. That value of 5 in VE2 is not to be multiplied when a corrrection is made. Obviously one could subtract 5 from VE1 after making that change if one wished. Sorry I did not think of that earlier.

Yes now you need only do one multiply exercise.

I wonder if your initial idle issue was a prom failure?

Quote: I then took the total VE% and dumped that number into VE1 from 800-3200RPM.

so you now have VE 1 table the same in all cells? I lost you there.

 

In my bin, 3600RPM is 41.02 4000RPM is 39.06. 4400RPM THRU 6400RPM is 37.11

No, no PROM failure according to WinALDL...

What I was saying is that I added 39.06 (the VE2 value from 800-3200RPM) and ADDED it to the already existing value in VE1, whatever that was. This gave me a total VE%. I placed this newly totaled VE in the Cells in VE1

For example: VE2 had 39.06 in every cell from 800-3200RPM.

I took the VE1 value at say 20 map & 1200RPM of 5.08 and added it to the 1200RPM value of 39.06 in VE2, this gave me a total of 44.14 which I placed into the cell of 20map & 1200RPM on VE1. Then I zeroed out the cells in VE2 between 800-3200RPM.