notice torque peaks at 4800-4900rpm with all 4 cams as port size limits flow at about the same point
but notice as cam lobe duration increases the peak power increases as flow rates thru the ports does lengthen the flow times and the rpm at which it peaks
GM Engine Vin Codes
Anyone going out looking for a 4.8L or 5.3L Truck based LS engine that has already been removed from the vehicleBeware, Because unless you can look into the spark plug hole with a scope or little camera to see the top of the piston or insert a wire and run it across the piston surface to feel if it's dished or a flat top It's hard to tell the difference between those two. However if you look for the 8th digit in the VIN It will tell you most everything you need to know.
1999-2006 Trucks, Vans & SUV
4.3L, VIN. X or W(2003+) (8th digit) 6.0L, VIN. U (8th digit), (LQ4) Trucks, Vans and Denali 6.0L, VIN. N (8th digit) (LQ9) Escalades & SS Silverado 4.8L, VIN. V (8th digit) 5.3L, VIN. T (8th digit, opt LM7) 5.3L, VIN. Z (8th digit, opt L59) 5.3L, VIN. B (8th digit, opt L33 05+ HO Aluminum and Iron Block with 243/799 heads)
2007+ Trucks
classic body style, 6.0L, VIN. U (8th digit, opt LQ4), Compressed Natural Gas and Gasoline
classic body style, 6.0L, VIN. N (8th digit, opt LQ9)
classic body style, 4.8L, (VIN. V, 8th digit, opt LR4)
classic body style, 5.3L, VIN. T (8th digit, opt LM7)
classic body style, 5.3L, VIN. Z (8th digit, opt L59)
classic body style, 5.3L, VIN. B (8th digit, opt L33)
classic body style, 4.3L, (VIN. X, 8th digit, opt LU3)
new body style, 5.3L, (VIN. 0, 8th digit, opt LMG)
new body style, 5.3L, (VIN. J, 8th digit, opt LY5)
new body style, 5.3L, (VIN. 3, 8th digit, opt LC9)
new body style, 5.3L, (VIN. M, 8th digit, opt LH6)
new body style, 6.0L, (VIN. Y, 8th digit, opt L76)
new body style, 4.3L, (VIN. X, 8th digit, opt LU3)
new body style, 4.8L, (VIN. C, 8th digit, opt LY2)