Actually I kind of thought the same thing about the commanded. Not too many ways I can think of to get that lean of an actual commanded afr for light load.

 

I am not sure it just started with the install of the longtubes.

 

Well I haven't taken the time to install EFI to be able to look at the log, but there really is no way at all the headers will have any effect on commanded afr. They may affect the actual some, but what is commanded is all in the programming. Off the top of my head I can only think of about 4 or 5 places that can change what is commanded and one of those isn't available for use in the US (lean cruise). There is a base stoich table, PE, DFCO and PN/Drive enrichment.

 

I'm running EFI Live COS5 and I'm commanding 16:1 at light load cruise. Runs great!

 

so I should be fine then right?

 

i thought the cos5 was only for the fbody os?

 

Covers many 01 and 02 truck OSs. You could change up to an 01 or 02 OS and do that as well.

Justin

 

right now i have an 01 truck os in my truck now, can i use this os or do i some how need to convert to an fbody os?? i guess i need to go back and visit efilives site..since i changed jobs i havent been keeping up on the tuning stuff lately

 

Load up the custom OS tutorial from the help menu. It will tell you if you can do it. It's not an f-body specific OS that you need.

 

ok will do..i gotta cos3 now and id like to have the cos5 for the nitrous