It's hit or miss with J/Y motors. First i would have pulled the valve covers and oil pan to inspect it. Look for sludge, metal, and just overall cleanliness. That and a compression test will tell you alot.

 

Never hurt to freshen it up though especially with everything you want to do..... Rebuild is not a bad idea, especially with not knowing mileage of engine to begin with

 

I was in a rush and I got a 3k mile warranty and 3 month warranty it's a daily driver and I needed my truck back. But I think I'm gonna do a rebuild kit on top of all the performance goodies. You're really helping a lot and I really appreciate that!

 

Anything else you recommend boss?

 

I have a J/Y lq4 that i'm picking up when i get home from work (another week). I'm going to open it up and see what it looks like and clean it up. If i like what i see i'm going to replace oil pump and timing chain set. Gong to install ls7 lifters/trays, cam kit, trunion kit, ls9 head gaskets and ARP head studs. Have the pan fitted with oil drain fitting for turbo. Do a little painting and put it in.

 

if you're that desperate to get your DD back in action, boosting a 5.3 to 600whp is going to be on the edge of reliability. JMO.

 

Why do you say that?

 

600 hp should be very achievable on a 5.3 we have sevral people down here pushing well over that on 4.8s and 5.3 and most daily drive them

 

Now the question is what does it take to achieve 600hp?

 

The question is why do want 600hp????? You are not going to hook it on the street with a stock setup. IMO 500hp would be plenty for a DD. It would be crazy fun, more reliable, and easier to obtain on a budget.


Take a look at this link.
It took him 20 psi on a 76mm to get 641hp/635tq. If i was in your situation i would not push it that hard on a DD just for the sake of having 600hp.... Gotta remember its a DD and you don't even know what shape your J/Y engine is in. Just something to think about.


https://www.performancetrucks.net/fo...-build-525016/

I bought the same On3 Kit except i went with the 70mm. He is using their 76mm. The kit is still in the box. I only opened it to take pictures lol. My goals changed and i'm not going to use it. If you would be interested in the On3 kit send me a PM. I need to get off my butt and post it for sale so i can buy more parts!