Fuel tuning.

[RockinRobin]

I have my EFI programmed to run at 12.4 AFR at wide open throttle. This has worked fairly well this spring but now that the weather is warming up it is becoming apparent that this is too rich. This is a 13.5:1 compression motor on 110 octane race gas. I've been told by the dyno guys that these motors like 12.8 or 12.9 AFR at wide open throttle. There is a test n tune available in my area tonight. My plan is to try 12.6, read plugs then try 12.8 I'm nervous about leaning it out too much.

 

[Mims Gt]

Is it a NA motor ?

 

[RockinRobin]

Is it a NA motor ?

Yes, na Gen 3 hemi stroker.

 

[Mims Gt]

very nice... I know when boosted they like them a lil fatter than a NA application so high side of 12 should be good

 

[RockinRobin]

RESULTS: according to the time slips, it liked 12.8 the best in bad air, about 3100 DA. I'll take it to a bracket race next week and see if I can make it more than 3 rounds this time.