I'm curious as to why some tuner tune to an AFR of 11.5-12 on pump gas under WOT and some to 11. Is this mainly for safety or to get the higher HP number that everyone loves to see? If it's safe to tune to 12 and make more HP why isn't it a common thing?

So the theory is to tune for 11.5 on pump gas for daily driving and use a VAFC to change the AFR to 12 at the track with better gas?

Thanks.

 

IT's a power/safety issue. Our cars are capable of running 12.0 AFRs on 93 pump on a daily basis, but since you don't see a significant power increase from at 12.0 over 11.5, then it's more common to see tuners shoot for 11.0-11.5 in order to stay away from the threshhold of danger. If the car still makes nice power with solid curves at an 11.2 AFR, then it should be safe for almost any weather conditions. Most people just have flashes that are never changed, so they need to have safe settings for both winter and summer. Those of us with self-tuning devices are able to tune to 11.5 or more on a daily basis for a little more power, because we can change the settings according to the conditions. The downside is that we have to stay on top of things and remember to constantly datalog in order to ensure that we don't run too lean on a daily basis.

At the track, if you use race gas, then you can turn up the boost and lean out the AFRs to 12.0 all day for mega power...

 

Thanks. I need to get a logger along with a WB and start making use of the SAFC on top of the flash. SAFC is currently in there for looks only .

 

Once you do those things, your tuning abilities will far surpass mine, so I definitely encourage you to do all of that. With wideband and an S-AFC on top of a flash, you can do great things. No reason to have the S-AFC installed if not using it, though...

 

quote:Thanks. I need to get a logger along with a WB and start making use of the SAFC on top of the flash. SAFC is currently in there for looks only .:quote



hey thats like me^^^i have a dynoflash and a safcII for looks right now(because i dont have a logger or wideband) and now for some odd reason im running rich warrtalon said he was help me out with that see what the hell is wrong

 

Wideband tuning on the street with an afc works very well. I ran with DCSilvrEvo after he tuned his afc with a wideband and the difference was very noticable, especially in 4th and 5th gear.





Hahaha, I always threw mine in the glove box so no one could see it.

 

How do you know you're running rich without a WB or logger ??

 

You're lucky you know someone who knows how to do it already and can help you. I have to start from scratch I have mines up in the class holder. I just use it to see what my peak karman is and to check my rpm at idle

 

theres realy not much gain runnign leaner. a buddy of mine with a built RX-7 made 5 more hp going from 11.5 - 12.5 afr.... i have autronic and above 15psi im at 11.4 afr.. granted i have a wideband that interfaces with autronic and datalogging capabilities... widebands have become more afordable these days so i would suggest buying one. either Innovate or PLX with the innovate you will have to purchase the rpm output so your datalogging will be usefull. but i would suggest this PLX device http://www.plxdevices.com/R-500_productinfo.htm it will be about $50 more than the LM-1 with RPM sensor.

 

Class holder?

Yeah, mine is in the glove box, too. There are no visible interior or exterior modifications on my car except the exhaust. I may get a factory tip welded on there just to remedy that, though.

When you start doing your own tuning, go to evotuners.net, and we'll get you started on the right foot. We have a write-up on how to use the S-AFC from scratch. It's what I used to get started, and I had no help locally, so it definitely works.

 

because of the smell it smells like fuel a lot, the wierd thing is it onl smells when im coming to a stop , i dont know whether to trust my apexi TT because it is attached to the o2 sensor output on the ecu harness, when im daily driving the TT reads 14.3-14.5. when i start to give it more gas(pedal) the reading gets lower im not even at half throttle it starts to read 12.3-12.5, i havent gone wot yet to check

 

narrowband is worthless. and its going to smell if you dont have a cat or with even a high flow cat

 

so i may be ok because i dont have a cat

 

Well if you have a ttm flash then your running rich. My ttm flash was sitting at 10.9 on the dyno and that's with some SAFC adjustments that I tuned at the track. I was trapping 111.99 on pump that way and leaning it out to 11.5 didn't do anything on the dyno. I bet on the street my a/f ratio would be completely different.

 

I have a apexi TT and I'm seeing the same thing as you. I suggest you look at the spark plugs rather then use the AF from the TT. I was paranoid as well I also don't have a cat.