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Cablebandit
April 7th, 2007, 01:23 PM
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
April 7th, 2007, 01:56 PM
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
April 7th, 2007, 02:26 PM
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
April 7th, 2007, 03:07 PM
So you don;t enrich further when in boost then? How much is Chad paying ya to have his banner ;)

onfire
April 7th, 2007, 03:35 PM
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.:cheers:

kbracing96
April 7th, 2007, 03:39 PM
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 :)

http://i3.photobucket.com/albums/y57/Kbracing96/Camandfueltable.jpg

Cablebandit
April 8th, 2007, 12:10 AM
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
April 8th, 2007, 01:17 AM
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
April 8th, 2007, 01:43 AM
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
April 8th, 2007, 01:49 AM
Tom, thanks...that was the understanding I came to. I is learnin' bossman!!!!
Tomorrow, I may get to see my first boost :)

onfire
April 8th, 2007, 03:20 AM
You're doing great. keep us posted on that killer hp.

kbracing96
April 8th, 2007, 03:33 AM
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?
That not entirely true ;). You can set B3647 for say 12.5 afr at 3000rpm and then set PE to 11.2 afr at 3000rpm but also set PE to not engage untill 125 kPa (about 4psi). You would have 12.5 afr to 4 psi and the then 11.2 on up. :) Make since?

Whippled 496
April 8th, 2007, 11:10 AM
That not entirely true ;). You can set B3647 for say 12.5 afr at 3000rpm and then set PE to 11.2 afr at 3000rpm but also set PE to not engage untill 125 kPa (about 4psi). You would have 12.5 afr to 4 psi and the then 11.2 on up. :) Make since?

Way to go KB, talk about throwing gas on the fire.....:)

Cablebandit
April 8th, 2007, 01:59 PM
lol...KB...it does make sense!!! I thought I was missing a table but i understand now. I just like to go a little leaner at low boost while coming off the footbrake...seems to help my 60'. I got a tbrake now and just wanted to understand what tables referenced what.
Thanks for your patience guys

kbracing96
April 8th, 2007, 02:33 PM
Way to go KB, talk about throwing gas on the fire.....:)

I like gas on the fire...makes BIG fire!!!! :D