tip in AFR
Thread Starter
Instructor
Joined: Feb 2008
Posts: 131
Likes: 1
From: Anderson IN
tip in AFR
hi all,
i am working through the tune on my 383 TPi and i am wondering if my tip in AFR might be a little rich. i understand the value will change depending on TPS% change and MAP delta but is there a rule of thumb for were the AFR needs to be during this phase?
Currently when i enter Tip in i am seeing AFR of around 10.5 down to around 9.8.
Is this too rich?
thank you for your inputs.
i am working through the tune on my 383 TPi and i am wondering if my tip in AFR might be a little rich. i understand the value will change depending on TPS% change and MAP delta but is there a rule of thumb for were the AFR needs to be during this phase?
Currently when i enter Tip in i am seeing AFR of around 10.5 down to around 9.8.
Is this too rich?
thank you for your inputs.
Race Director
Joined: Jun 2004
Posts: 13,934
Likes: 704
From: WI
To me it would be to rich yes. When I worked on that with my combo I wanted it to be the A/F I used in PE. On mine the AE has a few second decay so in your case it would be sitting at 10:1 for a few seconds which is unwanted. I'm surprised it doesn't have a rich stumble that low.
Thread Starter
Instructor
Joined: Feb 2008
Posts: 131
Likes: 1
From: Anderson IN
well i think it does have a small one at lower RPM's this is why i started thinking about it.
but the big thing is when i go WOT it feels a little sluggish for like .5 Second (doesn't really bog down or stumble) then it feels like it pulls harder when it goes to WOT fuel
so your goal was to keep tip in around PE, i run my WOT around 12.0 so your thinking my tip in should be about the same?
Makes since to me i will try it out to see if i notice a difference.
but the big thing is when i go WOT it feels a little sluggish for like .5 Second (doesn't really bog down or stumble) then it feels like it pulls harder when it goes to WOT fuel
so your goal was to keep tip in around PE, i run my WOT around 12.0 so your thinking my tip in should be about the same?
Makes since to me i will try it out to see if i notice a difference.
Race Director
Joined: Sep 2001
Posts: 14,641
Likes: 749
From: NEwhere Ohio
I have a bunch of these tables of my $da2 definition file for 92 and 93 vette ecm.
I too get afr's going to 10.0:1 the instant I hit the gas.
Are the tables you talk about labelled:
Accel enrich vs. Diffefential tps (multi).currently has values from 1.25% mutiplier at 0% tps going down to .25%multiplier at 50% tps
Accel enrich vs. Coolant temp (mult) has values of 1.5% multiplier (at -40c) going down to .03% at 116c
There are also 5 other tables starting with the label 'accel enrich'
I too get afr's going to 10.0:1 the instant I hit the gas.
Are the tables you talk about labelled:
Accel enrich vs. Diffefential tps (multi).currently has values from 1.25% mutiplier at 0% tps going down to .25%multiplier at 50% tps
Accel enrich vs. Coolant temp (mult) has values of 1.5% multiplier (at -40c) going down to .03% at 116c
There are also 5 other tables starting with the label 'accel enrich'
Thread Starter
Instructor
Joined: Feb 2008
Posts: 131
Likes: 1
From: Anderson IN
yes i believe those are the tables there is another table for the decay value.
the only one i have experimeted with is the decay value which is set arond 37%
I think i will try to bring down the accel enrich Vs. diffefentiel table so see if i can lean it out a little.
One other thing i was tossing around is with the decay value it might be holding the fuel in to long, maybe if i have it decay faster it might be better.
the only one i have experimeted with is the decay value which is set arond 37%
I think i will try to bring down the accel enrich Vs. diffefentiel table so see if i can lean it out a little.
One other thing i was tossing around is with the decay value it might be holding the fuel in to long, maybe if i have it decay faster it might be better.
Race Director
Joined: Sep 2001
Posts: 14,641
Likes: 749
From: NEwhere Ohio
what are your multipliers at?
(ex. I gave mine in a previous response)
I find it odd that I have a value of 1.5% (From the base tune Ive been using) at 0% differential TPS.
So the way I read it is if Im cruising steady state, the computer is automatically adding 1.5% extra fuel????? doesnt make any sense because theres no tip-in?
(ex. I gave mine in a previous response)
I find it odd that I have a value of 1.5% (From the base tune Ive been using) at 0% differential TPS.
So the way I read it is if Im cruising steady state, the computer is automatically adding 1.5% extra fuel????? doesnt make any sense because theres no tip-in?
Last edited by dizwiz24; Nov 15, 2012 at 01:07 PM.
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