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Grey Silver
July 31st, 2007, 05:51 PM
I'm working on a motor tune and looking for 13/1 at wot. My last log I had PE set to 12.7. I hit it in 1st gear at 5400 rpm and it gets to 12.7 at 6000 and stays there to 6800. After it shifts to 2nd it fattens up to 11.8 to 12.0 and stays like that to 6500. I'm just a beginner here. Does it need a little more fuel under load or can I bring it to 13/1 in 2nd and 3rd? And if so how do I make it happen?

GMPX
July 31st, 2007, 08:18 PM
Is that commanded AFR or measured?
Either way, there is many varying opinions on the ideal AFR.
For your ride somewhere between 12.3 and 12.7 should be fine.

Cheers,
Ross

Grey Silver
August 1st, 2007, 03:21 AM
12.7 commanded in B3618
12.7 measured in 1st gear
11.8 measured in 2nd gear
I'm trying to figure out why it gets fat in 2nd gear.

SinisterSS
August 1st, 2007, 09:31 AM
Is catalytic converter protection on or off?

Grey Silver
August 1st, 2007, 03:09 PM
Cat protection is off, I don't have cats.
Looks like the measured afr doesn't match B3618 at wot. Idle and part throttle are good.
How do I paste the B3605 table so you can take a look.
Thanks for the help.

Zfreak
August 2nd, 2007, 02:16 AM
Are you measuring AFR with a wideband? If so, where is the wideband located? The AFR calculations based off a narrowband 02 are almost useless.

eboggs_jkvl
August 2nd, 2007, 02:46 AM
I suck at tuning but...

What was you LTFT reading as you went WOT? LTFT needs to be negative. Anything positive and WOT work is futile.

I'll return to reading the other intelligent replies now.

Elmer

Grey Silver
August 2nd, 2007, 05:07 AM
I've got an lc1 on the truck and running in SD.
I talked to Jesse and I need to do the auto ve tune.
I started w/ a nitrous tune for a heads/cam 5.3. I'm working on a motor tune for a 370 w/ stage 3 heads, 11.2 cr, and a g5x3 cam. The truck idles and drives great and I'm ready to go to the track. Just need to get the AFR around 13:1 at WOT. Jesse said I can tweak the IFR a little to get me by for now.
Thanks for the replys