Oil change for modify GT

[established0589]

My 2002 GT is in need of an oil change. This will be the first since I bought it. The previous owner (Ford tech) rebuilt the engine. 160k on the dash, 1k on the rebuilt (it was 800 when I bought it). This just some of what he's done:

High volume oil pump with oil pressure gauge
Bama performance Tuner
93 Octane Gas Only
3.55 Gears
Race Clevite bearings
New rings and seals
Caster camber plates
19lb injectors
Transgo shift kit
Performance racing timing chain
BBK Throttle Body

I read in another forum that if your engine is modified and over 100k miles, do not use 5w20. So what grade would be appropriate with these modifications?

 

[rconaway]

Start with Mobil 1, 5w20 and a Mobil 1 oil filter. Watch it for 500 miles, then 1000 miles, and then 1500 miles. If the oil starts getting dark, then change it and start over. If the oil stays reasonably clean, then at least the last owner did a good job.

From there, watch your oil consumption. If you start needing more than a quart every 3000-4000 miles depending on how you drive, I'd do a compression test. If it's a little low across most of the cylinders, move up to 10w/30 but know that's going to accelerate wear further.

 

[Neuron]

New rings at 160K? At that mileage I would think oversize pistons and bore would be needed, he just honed it and threw new rings on the old pistons? Piston pins are steel and the piston is aluminum so guess what wears. Were the guides replaced in the heads? Not sure what the OP's definition of a rebuild is but I would not call it that, unless I am missing something.