I have just had my truck tested at the local Dyno with all my new goodies fitted (4# lower and JLP predator tune) and I am a bit disappointed in the results. After tweaking the AF a little to get it nicely into the mid 11s (because it was initially running a bit lean) my results were 366.6 RWHP and 464.3 RWTQ @65deg . Does this sound right, because I get straight to 12 PSI on my boost gauge and would have expected more, like 380 RWHP? Although when the truck was being dynoed I logged everything and noticed the timing was only at 14.75 deg @WOT. If I advanced the timing 1 more degree or so would it give me noticeably more horsepower and still be safe?

Previously I had the 2.8" upper and predator pulley tune and made 372RWHP and 452RWTQ @90deg, although this was running almost 19 deg of timing

 

whoa!! almost 19??? thats a lot!!! I think you could take the timing up a degree or maybe even 2 but i'm by no means an expert. just going by what i've heard about people running. But i think you'd be ok running 16-17 degrees timing, and that should also find you a bit more power

 

JKSTANG78 dynoed his STOCK 2000 L and made 369rwhp and 466 tq.
With a 4lb pulley, you should in the 400/500 club or real close to it.

 

I agree with birdy, that 16* would be a good idea. That's generally a safe number (93 octane) for most of these trucks. 17* is run by many, but I'm not sure that's safe (for me anyway) because I had some light ping at the top of second gear.

From what I've seen, timing is crucial in getting max power. You just don't want ping because that's the number one reason for blown motors (rods can't take the rattling).

 

I have run 16 degrees on the street for a year with no problems. Its sees WOT action everyday!

 

Depends on what type of dyno you used. Plus you can't compare numbers on your daily driver tune to someone elses race tune even though you have the same mods.

 

Will 2 degrees extra of timing make a noticable difference? Should it get me nearer to the 400 mark?
I do run 93 always and even when I had 19 degrees of timing with the predator pulley tune it did not ping.