[QUOTE=86_irocz-28;17459374]Gm claims baseline on this motor is 285hp at the flywheel(lm7 out of 03 avalanche) how the magazine got there baseline test i dont understand[/QUOTE

Car companies like gm give the engines a 'safe' tune in the vehicle running it slightly rich with less timing. That's why aftermarket power tuners can gain so much Hp and mpg by leaning it out and adding timing and why gm numbers are lower than it actually shows on a dyno with optimal tune.

 

Didnt think of that

 

start by reading here. https://ls1tech.com/forums/generatio...-me-first.html