hey guys i have been tuning my bolt on 01SS with a SD EFILive tune, and feel like i have finally been getting a hang of it all.

I am now curious what people suggest to be used as guidelines for what i want to tune it to. no DYNO is available to me at the moment so i am really trying to just get an idea of what i should have things set at.

For now at WOT i am at 12.5 pretty steady and tuning it right at 25 degrees of advance. i run 93 octane and am not getting any knock.

Should i add a little more timing? ?Maybe a little more lean?

with the leaner WOT and higher timing i noticed a SOTP feeling recently.

I was at like 11:1 and 18 degrees of timing.


Let me know what you guys think

thanks
Louie

 

get up to 12.8 at peak torque then lean it to 12.6 at peak HP, then richen a bit after peak HP till limits

 

12.8 is NOT peak TQ and 12.6 is not peak HP
do some reading and researching......

12.8 is PEAK HP and 13.2~13.3 is peak TQ on a Naturally aspirated car


get your WOT fuel up to around a 13.0 or so.....it will feel a LOT better.

Also with timing go up to 28 degrees at WOT and that will probably be your most you can go....some people run as high as 30 but they see no gain from 28 going to 30 degrees

 

ok cool i will be trying that out...maybe even tonight.

Thanks
Louie

 

Not to contradict you but, those AFR numbers aren't set in stone. I have made more tq at 12.6 on some cars then 12.8 and same goes with HP. It can vary but I have never seen more tq with a leaner AFR.

 

ok fellas so i have taken my AF ratio to 12.9-13.1 at WOT now, as well as setting my timing to about 28degrees at WOT.

There are a couple of questions that i have:

first off let me say that with back to back runs just with these changes the SOTP feeling told me that it got faster, definately felt better.

Ok with that being said i am picking up a little bit of knock retard. It happens in first gear(i roll into the throttle so i dont go up in smoke) as i am rolling into the throttle it starts to KR a little(about 4 degrees) and then as the rpms get closer to where i shift(6200-6400_ it starts to lower itself down...(declines to about 3 KR)timing

Then i shift to second...no KR in second but my timing is good at 27 degrees up to about 5300 rpm and then slowly falls to about 24.5 degrees up top at like 6000rpm or so.

third gear...i get knock retard again. about 4 degrees of KR at 4700rpm, and 3 degrees at 5500 rpm where i let off. timing in this gear is at 24 degrees at 4700 rpm, and 23 degrees at 5500 where i let off.

i checked a good majority of all of the tables and none of them are correcting spark for IAT, ECT, or any other factors. so my timing is a little screwy.

Also is it possible that my knock is Burst knock?

Well hopefully i can get some help with this tuning.

Thanks for all of the input thus far.

Louie Panayi

 

Sounds like burst knock to me.

 

Just passing on info that I did research and find, so dont sit here and act like I just made those numbers up.

 

Several things.

One, probably want to fiddle the knock retard attack and
decay around, make the attack rate maybe 1/4 its stock
value and decay, 4X or so (I don't know what EFILive calls
these, but what you want is to make the knock retard jump
less per detect, and dissipate quicker). Purpose being, to
see more clearly where KR hits, whether you have one little
trouble spot or a broad range of timing marginality, etc.
Stock, it just stomps and then stands on it, no info of any
use to tuning.

More fuel builds more torque in lower RPM but more fuel
increases burn time and you can blow energy right out the
exhaust once cycle time gets short; this is why you put it
fat (lower AFR, some of these replies seem upside down)
in the low range and lean it out as needed up top, trying
to burn as much fuel as you can in the cycle (limits are
plain chemical burn efficiency down low, available burn time
up top).

Distinguish timing at part throttle, transitional "response"
from WOT, steady-pulling timing. Best torque at WOT can
be had over a fairly broad range, there is a "flat top" that
exists and the best torque is a few degrees prior to onset
of ping. So if you've found ping, you're halfway there if
the ping is indeed your steady state, mixture all set, kind
and not residue from tip-in or some other engine event
than straight burn timing. That's what you want to dope
out, by peeling back the lid on KR. At any rate you will
do OK to set the timing back 3 degrees or so from what
makes ping, if you are tuning on a fine spring day you may
have some work to do later on for IAT, ECT adders in July
but what the hell.

Burst knock is a short series of pings that come from air
surges (such as tip-in, or transmission upshifting from a
high RPM to low and the air column briefly stuffing excess
down the hole, or whatever). Dynamic airflow is too slow
and smoothed to instantly track. If your fueling is generally
tight and you still get throttle- or RPM-event-triggered
knock detects then burst knock retard is an appropriate
way to cover that momentary error. Trucks use this stock
(and it sucks, due to stock tune values); F-bodies do not
at least in any meaningful way. If you want to play with
burst knock, see the Delta CylAir which is the trigger value
as the time-tick difference in Dynamic Cylinder Air values,
divided by 12.5 (PCM internal time-tick). You'd have to do
a little Excel crunching, make a column of =(X2-X1)/12.5
and look at it in detail at transitions, collect peak values
where you do and where you don't get transitional KR and
"set the bar" for triggering and then set the actual retard
values (to perhaps something like the KR values seen at
the trouble spots, as a start).

Do not go by "SOTP" feel for performance tuning WOT.
In part throttle, sure; do what feels good. But consider
WOT a special case and tune to some repeatable and
quantitative result. I recommend using something like
the logged MPH curve in your 3rd gear (or highest, non-
likely-to-be-busted) as a "poor man's dyno". You can
make charts that overlay the MPH-vs-time, start them
all from the same base (say, 40MPH) and then you just
keep goal-seeking the top line; keep fuel & spark notes.
If you find that the lines cross, like top line for low RPM
is 12.6:1 commanded or WB AFR but high RPM is one of
the leaner ones, then great; figure out the best parts of
each and stitch them together until you arrive at "best".

 

show me...why didn't you post where you found it? advise me on where i'm wrong, I honestly want to know these numbers

things may not exactly be set in stone but they do obey certain laws; there are differences due to other changes, such as atmosphere and other issues. Not to argue that you haven't made more power, because it is possible and someone probably has a dyno graph that they are going to shove in my face soon..but this is what I got out of it.

http://www.daytona-sensors.com/tech_tuning.html
scroll down to the AFR graph

from what i read that jimmyblue has said on AFR..he is right. that is what I have meant to say, however i think we have both misenterpreted this.

FROM JimmyBlue:
More fuel builds more torque in lower RPM but more fuel
increases burn time and you can blow energy right out the
exhaust once cycle time gets short; this is why you put it
fat (lower AFR, some of these replies seem upside down)
in the low range and lean it out as needed up top, trying
to burn as much fuel as you can in the cycle (limits are
plain chemical burn efficiency down low, available burn time
up top).

 

What the **** is this a ****** APA paper? I dont have to cite ****, I know what i read and it was LSx specific. I printed all the info and its at home. Im not saying that is the set in stone way to go nor did I ever say you were wrong. I would bet there are examples of doing it both ways and getting great results, just do what works best for your particular ride. Get off my goddamn back man.

 

never did i act like you made the numbers up...and I'm not on your back trying to correct you;

All I stated was that what either one of us probably meant to say was exactly what jimmyblue put to words...

More fuel builds more torque in lower RPM but more fuel
increases burn time and you can blow energy right out the
exhaust once cycle time gets short; this is why you put it
fat (lower AFR, some of these replies seem upside down)
in the low range and lean it out as needed up top, trying
to burn as much fuel as you can in the cycle (limits are
plain chemical burn efficiency down low, available burn time
up top).

 

ok i have found the Knock Fast attack Rate...and i put them all to 25% of what they once were, so i am good there.

Now as far as the decay i seem to have a problem. I am assuming that the "decay" parameter is Knock Retard Recovery Rate.
its info is: (quoted from EFIlive)
If timing has been retarded due to knock, but knock has stopped, then the amount of retarded will be reduced by this amount, every low resolution reference pulse (4x per crank rotation for V8, 3x for V6).


BUt unfortunately every single value that i have is set to 0. from 0 rpm all the way up to 8000 rpm every value is 0.

any input for this would be appreciated.

Thanks
Louie