AFR Curves (cobalt ss/sc)

[an0malous]

So im curious what everyones feelings are about A/F ratios.

no, not what to run, but what to run WHERE

now ive been told that being a little richer down low can help with torque.

what are your experiences with A/Fs with relation to RPM?

where do you like to run a little richer, where leaner

discuss

[Ghost Rider]

Run on the lean side up to max torque. Then richen it up till the redline.

[an0malous]

interesting. thats kinda the opposite of what ive heard.

How did you come to that conclusion? dyno testing??

it does seem to reflect what most stock tunes seem to do though.


thanks for the input btw

[Ghost Rider]

basically the reason I say that is because running on the lean side will help to squeeze out that last bit oh hp and get you to max torque faster. Then you richen it up as you move to the redline so you don't go boom at higher rpms.

I have also have heard of people keeping it lean all the way to when tq and hp curves meet. Then start richening it up.

Darryn

[an0malous]

thanks again darryn. something for me to try

[PSYKOSTEVO]

I don't do what he said.........

Anomolous> what size injectors are you running? I can send you injector flow tables and PE enrichment for my stuff so you can experiment with what you like. All of my tunes drive and idle like stock unlike all those other baboons out there who think they know 60# tuning, and then complain when their car dies at stop lights.

[an0malous]

60s
im quite happy with my injector setup so far, never once stalled in over 6 months. idles smooth.

what im curious about, is everyone says "i run 11.3 afr, or i run 11.5afr"
but in truth, thats not getting the best out of your car.

Im curious what people are doing as far as dynamic PE tables.
IE are you running 12.0 from 3-4500, then richining up to 11.3 by redline?
the opposite?

etc etc....know what i mean?

any dummy can punch 11.3 into the PE and call it a day.
but i know more can be done there

[S2H]

you should be extra rich at peak torque...lean back out some to go to peak HP and then start richening up after peak HP...
an example would be
1200rpm-2400rpm 12.8afr
richen up to 12.2 for peak torque
lean back out to 12.5(even as lean as 12.8 depending on how much PSI you are pushing) for peak HP
back to 12.2 by redline/shift point

thats best recipie for success...
I've shaved up to a half second off of other peoples tunes just by following the basics listed above...
actual AFR's need to be determined on the dyno...and then take those #'s you found and make them match on your wideband on the street/rack

[an0malous]

you should be extra rich at peak torque...lean back out some to go to peak HP and then start richening up after peak HP...
an example would be
1200rpm-2400rpm 12.8afr
richen up to 12.2 for peak torque
lean back out to 12.5(even as lean as 12.8 depending on how much PSI you are pushing) for peak HP
back to 12.2 by redline/shift point

thats best recipie for success...
I've shaved up to a half second off of other peoples tunes just by following the basics listed above...
actual AFR's need to be determined on the dyno...and then take those #'s you found and make them match on your wideband on the street/rack

EXCELLENT!!!! thats exactly the type of input i was hoping for.
I think my projected AFRs would be slightly on the richer side of that,
but the concept is what im interested in
thank you very much!

[S2H]

I've tuned 15psi with the 12.2-12.5 scale there....never made any more power by making it richer....didnt hurt anything at 12.2-12.5....
just dont go crazy on the spark advance....
I've been up in the 20*-22* spark on 10 PSI with no knock and no issues...
IIRC the 15psi was 15-18ish on spark

less spark at peak torque..more spark at peak HP...back off of spark at redline

[MemphisR24]

I've tuned 15psi with the 12.2-12.5 scale there....never made any more power by making it richer....didnt hurt anything at 12.2-12.5....
just dont go crazy on the spark advance....
I've been up in the 20*-22* spark on 10 PSI with no knock and no issues...
IIRC the 15psi was 15-18ish on spark

less spark at peak torque..more spark at peak HP...back off of spark at redline

That is some good advice. I'll be trying your method shortly

But there comes a point where too high of an a/f is not going to make you any power....I have ran 12.7-12.9 in my boosted car and it seemed slower (wasn't any knock) than when I make it run low 12's. Right now I have it running 12.0 across the whole board so i'm gonna be playing with that tonight