Always 11 afrs?

[bcjjones]

Got a pretty damn decent tune if I say so myself. Pulls like a rocket, pretty happy for my first tune. Should've got into this a long time ago.

Another question I have is, under boost, I mean any boost, are the afrs always supposed to be at or around 11 for our cars? Meaning during normal driving, under light throttle when in low boost are the afrs still supposed to, again, be at or around 11 afrs?

Just doesnt seem to be the best thing for gas mileage!

 

[Gstclipse69]

When at idle and cruising the afr should be bouncing around 14.7. When you hit full boost then yes keep the afr at 11.0 assuming you are running pump gas. I think many keep it a little leaner than that as the turbo is spooling, until you hit full boost. Just make sure you dont see any knock. Tuning is fun once you get the hang of it and understand what your trying to accomplish.

 

[bcjjones]

Yea I understand it pretty well. I also understand at cruise should be around 14.7 even as lean as 15.5. Also understand at full boost using pump gas (93) at full boost WOT afrs should be 11 or a little leaner depending on setup/knock.

My questions is, though, while getting up to crusing speed while simply at part throttle obvioulsy I still get into low boost just going through gears. Anywhere between 1 and 10 psi at part throttle just nornal driving. Should those lower boost/lower throttle afrs still be at 11? Obviously also im not able to change afrs per load, so changing afrs under part throttle/low boost would still be the same afrs as wot while climing through low boost to reach max boost. If that makes sense at all

 

[boost97gst]

Look at the stock tables in link. That should give you an idea. It depends on your turbo, but under 10psi i would think anywhere from 11.5-13:1 would probably be ok. It all depends too on the load factor.

 

[Calan]

Look at the stock tables in link.

According to his profile, he's running an Ostrich/Jackal; not Link.

 

[YZFR1]

My questions is, though, while getting up to crusing speed while simply at part throttle obvioulsy I still get into low boost just going through gears. Anywhere between 1 and 10 psi at part throttle just nornal driving. Should those lower boost/lower throttle afrs still be at 11? Obviously also im not able to change afrs per load, so changing afrs under part throttle/low boost would still be the same afrs as wot while climing through low boost to reach max boost. If that makes sense at all

To answer your question, low boost afr's don't have to be the same as full boost afr's. Also, depending on the size of the turbo and how much cfm it is actually pushing. There is no set answer for this, for obvious reasons. For example, on smaller turbo's you could easily do 13 afr for 5 psi, 12.5 afr for 10 psi, 12.0 afr for 15psi and so on. This is also going to make the car a lot more responsive at part throttle

 

[hotrodssnova]

Obviously also im not able to change afrs per load, so changing afrs under part throttle/low boost would still be the same afrs as wot while climing through low boost to reach max boost. If that makes sense at all

If you are running Jackal, you can log your load values and and use that with your map info and make the needed changes. Have you changed the target afr map to what you want? Jackal is a good tool with lots of settings. Have you posted over on haks site?...ds-map?

 

[bcjjones]

Well despite the name, the Big 16g, as yall know is considered a small turbo. With my current tune, from 1 psi to 20 im running 11 afrs. I'm assuming that, since obviously there is no set answer, I can lean it out as much as possible in the lower boost and that AFR is only determined by when I start to see knock? I think anything past 15 ill just leave at 11, because usually if im at that boost level my foot is pretty far into it.

I have set my goal afrs under load, they are at 15.05 in the low load ranges and 11 in the higher load rows. I just wanted to be sure that under boost, its not always required or best to be at 11 afrs. I do post over at the dsmap website but I just like tuners a lot better! I have no comparison but really do love the Jackal program.

I appreciate all yall input, let me know if there is anythine else I need to be concerned about!

 

[91stocker]

Just keep an eye on the kr. If theres no knock id lean it out a bit. My car seems to like 11.5-11.7 ish. Lean it out too much and you will start to lose power too though.

 

[bcjjones]

Okay cool. Maybe I can squeeze a little better gas mileage out of daily driving. 1g's are always supposed to be tuned strictly around knock correct?

 

[banshee88]

idk if this will help but with dsmlink if u wire a wideband up and it constantly shows 11 it
means you need a input buffer

 

[1983gsp]

I tuned mine to 15.5 cruise, 13.0 0-5psi, 12.5 5-10psi and 11.5-11.0 10psi+
Log your load, map, knock, rpm, o2, and timing. Get the afr's in line then tackle timing. Increase timing till you get knock and then back it off a degree or two until it goes away. Look at your load row and rpm to determine what timing value to change
I've been running jackal for 2 years now and absolutely love it.

 

[DSMTyson]

I like my AF ratio to be in the 13-12.5 range during spool up. Then I richen it up to 11.7-11.5 when I hit peak boost.

 

[YZFR1]

Okay cool. Maybe I can squeeze a little better gas mileage out of daily driving. 1g's are always supposed to be tuned strictly around knock correct?

That is an incorrect concept, you tune any car for the best power delivery (or whatever might be the goal) while keeping an eye on knock.

On another note, air fuel ratio has very little to do with knock. Not on my own car, but on a load bearing dyno i first hand witnessed the effects of afr on knock and power delivery. We sweeped it from all the way rich to all the way lean while keeping an eye on knock and power. Conclusion was, it has very little effect on both.

 

[xxNocturnalxx]

^Really? AFR directly effects knock both on the lean side and rich side and timing. Your timing was probably overly conservative.

 

[YZFR1]

Timing is where it is at yes, it was very conservative. I don't think anyone would want to do this experiment otherwise.

 

[bcjjones]

I tuned mine to 15.5 cruise, 13.0 0-5psi, 12.5 5-10psi and 11.5-11.0 10psi+
Log your load, map, knock, rpm, o2, and timing. Get the afr's in line then tackle timing. Increase timing till you get knock and then back it off a degree or two until it goes away. Look at your load row and rpm to determine what timing value to change
I've been running jackal for 2 years now and absolutely love it.

Yea thats exactly how I have tuned it with the exception of yhe leaner afrs on lower boost. I have an aem wideband which doesnt log correctly. I usually take a video of the afrs and rpms while logging the same pull and adjust afrs based off the videi. Not as reliable as being able to log them but it works pretty well. I usually lpg battery volts also and injector duty just when raising boost.

I also have always seen/read afrs being in direct relation with knock. Since owninh my car ive always experienced knock when too rich and when also running too lean. Though timing does play a big role also.

 

[xxNocturnalxx]

I see, didn't realize it was an experiment haha