out of curiosity, has anyone replaced just the rod bolts & valve springs and is this enough to safely up the rev limit? Also how much higher were you able to go?

Down the road Id like to set my rev limits higher, but wouldnt want to do it recklessly...

 

Are you planning on putting a cam in? No point to rev higher if it doesn't make power up there.

 

Although the Stock LS2 will rev to 6.2, if you look at any stock Base line tune dyno chart, will see that the motor HP curve goes flat around 5.5K instead.

GM does starts to lean out the AFR (Air to Fuel ratio) at 5.2K to keep the HP climb a touch more after that point, but does not lean out the motor enough to keep the climb steady with the timing advance (think of it as more of a buffer to get you to short shift instead).

Base line stock tune is steady with a touch more lean after 5.2, and by leaning out AFR more as needed, you can keep the HP curb climbing a touch more, instead of going flat (gain around 20HP over the stock tune).


Now the bad new, fuel (lower AFR) is engine cooling, and when you are leaning out the AFR, your just causing more heat due to less fuel cooling. So in stock form/cam, to keep the HP climbing (what little of it) after 6.2K. you will be running the engine so lean causing more heat, that it's not worth it.

Stock ls-2 tuned RWHP numbers, and pay attention to the AFR values as the bottom and what they are doing after 5.2K to keep the HP climbing upwards, instead of going flat or negative. Also to note, there is no "GM buffer" for the last of revs to tell you to shift before you go flat, and you will bounce off the rev limiter hard since the motor gives not sign of going flat before it hits the rev limiter (think of the stock tune as a mid range pulling motor, while a tuned motor just wanting to pull hard to red line instead).