I am aiming for 400HP, and i think it will be sience fiction, so i would have to see at least 300 ( reality kicks in there ), and i think it is doable with my set up, and this all will be on a P90A.. ( BEWARE not all p90a's are Hydrolic!!!)
Id say the l28 has enough potentential to pull under 6K and even to make the 300 benchmark hopefully more.
WHo here made in excess of that with a p90a ???
My set up is a 440 or 480 cc injectors t3/4 will be set at max 20PSI for the stock HG
3"exhaust
custom manifold IC, MsS , stock internals for now ( if the HG goes ill go o ring orso)
however back on track , the discription you give sounds like a turbo that could have been run WO an aircleaner, but a worn turbo does not mean the engine is bad aswel. shutting the engine when how will ruin a turbo, not an engine.
There are so many things that will ruin a turbo fast ...
But yeah buy a gasket set, and rings and main bearings, replace them all so you'll know it is good...
This will give peace of mind, and a solid base