My daily for the last 6 years has been a 72 El Camino with a 5.3 and 4L60E. I changed to an LS2 cam and changed valve springs. It has headers and the Trailblazer intake. It was 315 hp to the wheels on a Mustang dyno. We stopped the pull at 5600 rpm because it was running out of fuel. Power was still climbing. It was a junkyard engine.
Nice. This is a bone stock 99 5.7 LS1. I figure I will clean up the heads and change the seals, have them check it to make sure they are true and change the springs. Use the 5.3 short block. I am going to retain the original Camaro intake and throttle. I'll probably put a set of long tube headers on it, if they will fit, change the cam to a mild street/tow type of cam and call it good. I'll try and make it as sanitary as possible, but I am not spending a ton of time or money trying to make it look like a gen 1 sbc. But, I do think I will put a Ford emblem on the intake just to piss off the purists. 300 HP is plenty for me on this truck. If I end up with more, it's all gravy.
What I really like is that it leaks nothing. I park anywhere and there are no spots of anything. I do have the headers from Holley made for the A body. The engine had 45k on it. The trans was from a Camaro and had been rebuilt. For engine management I am running a Megasquirt MS3 and controlling the transmission with a Microsquirt. It is nice to be able to program the shift pattern.
The stock setup is geared towards torque, but it has a nice wide torque curve. Like idle to 5000 or something.
There are quite a few towing cams available. Tons of info on the old web. I will run the factory ECU and probably a stand alone computer of I use an automatic. I am leaning towards a 5 speed stick, just to minimize the extra crap for tranny coolers etc. Plus, I prefer controlling my shift point, especially when towing.
The stock LS ECU (if from an automatic vehicle) will control a 4L60E/4L80E with no other stuff needed, and you can customize all tranmission operations in the ECU with HP Tuners, FYI.