Autotune Tip - expanding usable AFR range

[ateick]

I've been playing around fine tuning my fuel map and ran into an interesting issue I hadn't seen documented anywhere. Hopefully this helps someone down the road.

I was working on the WOT AFR target which I had set at 10.5 and I noticed Autotune wasn't creating any trims in the 80%-100% TPS cells. Target was 10.5 but I was seeing 11 AFR on gauges and datalogs.

Emailed with Chris at Dynojet and he knew right away the issue. The PC5 has limits to what it will Autotune to. Chris provided me a firmware update which opens up Autotune to has high as 18.0 and as low as 10.1. These ranges aren't covered by the normal firmware as I guess they are considered out of the norm or extreme.

 

[MrSled]

I've been playing around fine tuning my fuel map and ran into an interesting issue I hadn't seen documented anywhere. Hopefully this helps someone down the road.

I was working on the WOT AFR target which I had set at 10.5 and I noticed Autotune wasn't creating any trims in the 80%-100% TPS cells. Target was 10.5 but I was seeing 11 AFR on gauges and datalogs.

Emailed with Chris at Dynojet and he knew right away the issue. The PC5 has limits to what it will Autotune to. Chris provided me a firmware update which opens up Autotune to has high as 18.0 and as low as 10.1. These ranges aren't covered by the normal firmware as I guess they are considered out of the norm or extreme.

Well thats just stupid.. good info but why not have it available without a call and update?

 

[ateick]

All I can think of is they are trying to safeguard against gernading using Autotune just in case someone puts in a crazy AFR target value. Would have been nice to know this ahead on time though.

 

[MrSled]

All I can think of is they are trying to safeguard against gernading using Autotune just in case someone puts in a crazy AFR target value. Would have been nice to know this ahead on time though.

Good point!

 

[Macheater]

May I ask why you are targeting such a rich a/f? Running E-85?
10.5 sounds overly rich, even with lots of boost.

 

[ateick]

I settled on 10.7 WOT. From my research that seems to be the consensus for the SR Viper Hurricane 190 kit. I'm sure 11 is likely fine but I'd rather be cooler and safer.

 

[MrSled]

I settled on 10.7 WOT. From my research that seems to be the consensus for the SR Viper Hurricane 190 kit. I'm sure 11 is likely fine but I'd rather be cooler and safer.

Below 12 would be target from my understanding. 11.9

 

[ateick]

There were lot's of threads about WOT afr for these kits out there. I had a big fuel map issue when I added this to my '18 so I think I read them all. LOL! The general consensus is 10.5-11. Even Dave indicates in one of the threads that the kit is designed to run at 11.0 WOT. I've landed at 10.7 just to add a buffer and account for any questionable fuel I may end up with.

 

[MrSled]

There were lot's of threads about WOT afr for these kits out there. I had a big fuel map issue when I added this to my '18 so I think I read them all. LOL! The general consensus is 10.5-11. Even Dave indicates in one of the threads that the kit is designed to run at 11.0 WOT. I've landed at 10.7 just to add a buffer and account for any questionable fuel I may end up with.

ok, just seems fat.

 

[Macheater]

ok, just seems fat.

Yup, AND THIRSTY.
Dave knows how it works, if he's recommending 11.0 then he's already included a "safety factor".
But it's your sled, you make the call.

 

[ateick]

Thanks guys. I may back it off a bit as I play around with logging and Autotune. First time with a turbo so I'm a bit freaked out about blowing it up. Been a fun winter so far squeezing the trigger though and learned alot. Appreciate the feedback.