I have a 2003 gmc 5.3 3.73 G80 ex cab Z71. Mods a long tubes, no cats, true dual, Asp, electric fans, predator custom tune, custom air intake. Do you guys think I could shift at 6000. I am asking because right know I have my shifts at 5850 and it is still pulling good when it shifts. Let me know what you think. My dyno numbers are 286 hp and 307 tq If that helps. Thanks

 

Redline it I do!

 

Throw some ARP rod bolts and some springs and go to 6200+

 

you can go to 6000 with no probs. I was shiffting my 4.8 at 6100

 

In your dyno chart, where did power start to drop off? Or, did it?

 

On the dyno we only ran to 5600 and like 5150 was peak horsepower but it wasn't dropping off that bad maybe like 5-10 horsepower from 5100 to 5600. But at 5800 it is still pulling hard.