3 bar help

[Cablebandit]

i am running cos5 and 3 bar (thanks Tom and Chad!!)
I want to run main ve and boosted ve for fueling and not PE. It seems thats the best way...correct me if I am wrong. How do I make sure my fueling in boost is coming from the boosted ve table and not PE?

[Tordne]

Any VE table is used to describe fuel requirements are the specific points. It sounds like you are confusing the VE table it with commanding a mixture, which is where the Open Loop B3647 table, or PE would be used. Given that the B3647 table doesn't extend past 100 kPa I think you'll need to use PE mod fueling above that manifold pressure.

[kbracing96]

Any VE table is used to describe fuel requirements are the specific points. It sounds like you are confusing the VE table it with commanding a mixture, which is where the Open Loop B3647 table, or PE would be used. Given that the B3647 table doesn't extend past 100 kPa I think you'll need to use PE mod fueling above that manifold pressure.

Actually, when your using the COS, the PCM will use which ever value is richer, the 100kPa in B3647 or the PE table. FWIW, I have my PE set to all 14.7 and use B3647 for commanded A/F in my tune.

[Tordne]

So you don;t enrich further when in boost then? How much is Chad paying ya to have his banner

[onfire]

i am running cos5 and 3 bar (thanks Tom and Chad!!)
I want to run main ve and boosted ve for fueling and not PE. It seems thats the best way...correct me if I am wrong. How do I make sure my fueling in boost is coming from the boosted ve table and not PE?

Look at the B3647 that I sent. That is the Primary commanded AF ratio. The VE table should be tuned so your actual AF equals what is commanded. The PE should be set slightly leaner at the set points so it is a backup in case of a failure. Example if your wot B3647 is set for 11.5 : 1 at max boost, set the PE to 12.0 as a safety valve.

[kbracing96]

So you don;t enrich further when in boost then? How much is Chad paying ya to have his banner

Haha, paying me...If some one would buy something because of me, maybe....

Here is how I enrichen for boost

[Cablebandit]

oh no...now i am more confused.

so i use 3647 to define commanded a/f and use the main ve table to reach the 3647 numbers...makes sense. That only goes to 100kpa and thats where i am lost. A0009 is the boost ve table....i use that to reach the commanded a/f in what table? I dont understand how to dial in a/f for 2 psi @ 3000rpm vs 20 psi @ 5000 rpm...seems like i need a boosted equivalent of the 3647 table to reference for commanded a/f. Please help a dummy!!

[Cablebandit]

after reading more (which i am sure you all are wishing i did) It looks like while in
boost, you are only able to command one AFR at each rpm set point(via PE or 3647) giving the same afr at 2psi-3000 rpms vs 20psi-3000 rpms. I think thats where my confusion was coming in. So i could not run 12.5 afr for 3 psi/3000 rpms vs 11.2 afr for 20psi/3000 rpms........both boost levels are going to have to be at one afr at 3000rpms. Is this correct?

[onfire]

after reading more (which i am sure you all are wishing i did) It looks like while in
boost, you are only able to command one AFR at each rpm set point(via PE or 3647) giving the same afr at 2psi-3000 rpms vs 20psi-3000 rpms. I think thats where my confusion was coming in. So i could not run 12.5 afr for 3 psi/3000 rpms vs 11.2 afr for 20psi/3000 rpms........both boost levels are going to have to be at one afr at 3000rpms. Is this correct?

You might be able to "hack" the boost VE table to do that...but you don't want to do that.

1. Main VE table is used to make the actual af equal the commanded af in 3647 at part throttle anf transition throttle.

2. Boost VE table is used to make the actual af equal the commanded af in the last columns of 3647.

3. Last column of 3647 should be richer than PE so 3647 will be primary.

[Cablebandit]

Tom, thanks...that was the understanding I came to. I is learnin' bossman!!!!
Tomorrow, I may get to see my first boost