Hi .....
I have 2006 truck 4.8L 5M I swap the engine to 6.0 Heads&cam
the problem is .....
in the AFR from 2000 - 4000rpm 15 -14.3 afr and 4000-6000 9-11 afr
I add more fuel still the reading same what is the problem
some body advice me

thanks ,

 

Sounds about right to me. Up to 4000 rpm you are in closed loop mode and the AFR will bounce around 14.7 (The bouncing is to keep the cats happy, too complicated to explain here). Above 4000 rpm the engine is in power enrichment (PE) mode which should be about 12 - 12.5 for NA and 11 - 11.5 for FI. Yours looks a bit rich, but you say you are adding more fuel? What is it exactly you are trying to do?

 

If you are seeing 9.xx to 11.xx afr above 4000rpm you need to pull fuel unless you have a supercharger/turbo.

Did the 6.0L maybe have bigger injectors than your other engine? Or did you reuse the injectors from the 4.8L?

 

I try all thing add and pull it's same I change the injectors 42 also same ...!!!!!

 

you probably need to change the PE enable point/delay...and then lean up the mixture up top.

 

I will try

 

Heres my tune file if your interested in taking a look. I'm running a 6.0L with the 4.8L injectors. 224/224 .581/.581 112lsa cam. Heads milled .035

 

 

Oh i know, i need to buy 1 more 6.0L injector and then i can put them in.

 

4.8 injectors and 6.0 injectors are the same, the 8.1s are larger