So my buddy has a LS in an EG with Uberdata. He's got I/H/E and a fuel rail that's about it. I was thinking since stock Honda fuel and iginition maps are fairly conservative could I take up a couple degrees of timing out in the WOT columns for some extra HP. We are using my wideband to tune fuel maps. My personal Turbo LS integra is street tuned, but I just set conservative timing in boost along with a 11.8-12.0 AFR in boost.

My question is how much timing could I add in WOT (or other areas) to have some gains yet still keep it fairly safe. Also what should I shoot for as far as top end AFR's....13.5?.....14.0?

Any serious info is appreciated Thanks guys/girls!


Modified by adseguy at 1:03 AM 2/21/2005

 

dont tune rich....thats bad habbit in turbo tuning...when you tune 12-11 a/f ratio all your effectively doing is slowing down the burn...to accomplish the same thing tune leaner and pull timing with uberdata....for turbo 12.5-13.5 seems to be good a/f ratio on boost...some motors like to run a little richer then others to make power....off boost 14-14.5 is a good range to keep somewhat decent fuel economy driving around town

 

there is really no way of knowing unless your on a dyno. you can add a little timing and the car will feel a little more peppy.
the idea is to have the combustion process end at about 25 deg. atdc; where the force will be greater to push the piston down.
the richer you run the more timing you need, since; as sayd above; you are slowing the burn down.

 

I know in a turbo setup a lot more pressure is exerted and more heat in created in the chamber, that is why you want to run a lttle overly rich to prevent detonation. this is also the reason you pull timing!

What I was asking was on a fairly stock LS the engine is tuned fairly conservativly...if this LS were to run 91 octane how much timing can I ADD and/or how much leaner can I run to have a peepier car...I just would like a few numbers like say 2 degrees advance or something like 14.0 AFR in low vaccum (WOT)


This Pic is for boost...notice the 13.0 for the lower vaccum area...could I lean this out a little for a little more performance in an NA engine. Again, I will have no Dyno I just would like some ideas...anything ....thanks

 

Comon you NA guru's what do you aim for in WOT as far as AFR's go and on a fairly stock motor how much timing can I add for a little extra power (nothing crazy)

 

As you say in a turbo car you pull timing to prevent detonation; because more timing creates more pressure and heat in the chamber.

i would up the timing a little all over the board; how much? well..
consider that a slock ls runs about 28-29 deg. at higher rpms, a stock gsr runs about 1-1.5 more deg. at higher rpms.
So im guessing as you say add a couple of degrees all over, but its just a guess.

As far as the afr, your on the right track.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mmuller &raquo;</TD></TR><TR><TD CLASS="quote">a stock gsr runs about 1-1.5 more deg. at higher rpms.
</TD></TR></TABLE>

Thanks I didn't know that .... anyone else

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy &raquo;</TD></TR><TR><TD CLASS="quote">I know in a turbo setup a lot more pressure is exerted and more heat in created in the chamber, that is why you want to run a lttle overly rich to prevent detonation. this is also the reason you pull timing!

What I was asking was on a fairly stock LS the engine is tuned fairly conservativly...if this LS were to run 91 octane how much timing can I ADD and/or how much leaner can I run to have a peepier car...I just would like a few numbers like say 2 degrees advance or something like 14.0 AFR in low vaccum (WOT)


This Pic is for boost...notice the 13.0 for the lower vaccum area...could I lean this out a little for a little more performance in an NA engine. Again, I will have no Dyno I just would like some ideas...anything ....thanks

</TD></TR></TABLE>

"that is why you want to run a lttle overly rich to prevent detonation." pulling timing prevents detonation without wasting fuel...no reason to run rich...
read learn

http://www.innovatemotorsports...h.php

"Many people with turbochargers believe that they need to run at very rich mixtures. The theory is that the excess fuel cools the intake charge and therefore reduces the probability of knock. It does work in reducing knock, but not because of charge cooling. The following little article shows why."

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2k.civic.si &raquo;</TD></TR><TR><TD CLASS="quote">

"that is why you want to run a lttle overly rich to prevent detonation." pulling timing prevents detonation without wasting fuel...no reason to run rich...
read learn

http://www.innovatemotorsports...h.php

"Many people with turbochargers believe that they need to run at very rich mixtures. The theory is that the excess fuel cools the intake charge and therefore reduces the probability of knock. It does work in reducing knock, but not because of charge cooling. The following little article shows why."</TD></TR></TABLE>

Cool...Thanks for the article. I agree with the author that I could probably run 13.0AFR and I would be OK, but if I get a bad tank of gas or my intake charge is very hot on a summer day or anythig else out of the ordinary I have a little more room to play with that's why 12.0 is conservative and not ideal so I may not produce that extra 5-10whp but I will be safer

Now back to the NA part...do you have any ideas 2k.civic.si?

 

if your fuel management is setup properly your ecu will make the proper adjustments for air intake temp...thats why you have a air temp sensor on the intake ....and where did you get 5-10whp??? ive seen half a point richer/leaner of the a/f ratio on some turbo cars make 40-50whp more....some engines are real picky about a/f ratio...to rich or lean they fall flat on face

as for n/a setups....you have to tune it on a dyno to find best a/f ratio....higher compression n/a motors seem to like around 13.0:1...but a mostly stock lower compression motor....im guessing its gonna wanna run pretty lean to make most power....but no telling without dyno....if all you have is the wideband...to be safe just tune around 13.0:1 at full load and around 14.0-14.5:1 partial load

here is an example...not in a/f but its in lambda...to figure out a/f from lambda take the lambda number for ex. say you have lambda of 0.85 take 0.85 and multiply it by 14.7 .85x14.7= a a/f ratio 12.495:1 a lambda of 1 = 14.7:1 just for reference






Modified by 2k.civic.si at 9:14 PM 2/21/2005