snketr

iTrader: (3)

Just picked up a 3500 Express cargo van with an LQ9 and 4l80e for my swap. It has 242k miles on it. I drove it the 10 miles back to my house and it ran strong and temp only got to just under 210. It has it's normal oil leaks that I can tell. My plan is to drop it in my 67 el camino and drive it. I'm not drag racing it or forced induction. I thought with the miles, maybe pull it apart and put new bearings and rings and ARP rod bolts? Or should I leave it alone and hope for the best?

SCJW

My high mileage LQ4 looked pretty good when I pulled it apart except for the cam bearings. It ran fine with good oil pressure when pulled, but the cam bearings just felt rough. I'm fairly new to the LS world, so I don't know if this is common, but it would be worth checking since the engine is out.

ddnspider

iTrader: (26)

I'd pull the pan and valve covers and take a peek inside. Pull the spark plugs and get a borescope in there and see what the cylinders and piston tops look like. Maybe consider a setup of stock replacement valve springs. also consider valve stem seals since it's easy to do out of the car. If everything looks good then run it.

tblentrprz

How long do you plan to run it before pulling it for refresh?

If you plan to install and leave it for 10s of thousands of miles, I would:
Pull it apart
Check bearing condition
Check bore condition
Check piston and ring condition - usually bound up in gunk
Check ring gap to see how worn they are
Check valve sealing - see how bad they leak.
I'd replace the cam and springs - easiest hp mod you can do. Include lifters too.
While springs are off - verify guides, valve and seat faces. Install new valve seals.
Replace oil pump pick up O ring seal
Replace oil pan gasket, all cover gaskets, front and rear crank seals.

Depending on what you find and how long you'd like to run the motor, will determine what you'll need to do.

Add a catch can inline with the PCV system to evac the motor and keep oil out of intake track.

Don't need rod bolts.

CattleAc

iTrader: (7)

This. You're not going to use the truck pan anyway. New oil pump, new o-ring, new can retainer, new rear cover seal, new pan that fits your chassis...send it.

snketr

iTrader: (3)

I planned on doing gaskets, sloopy stage 2 cam, springs, lifters, valve seals no matter what. I'll check ring gaps, bearings and such since I'll have it on a stand an pan off it. I'll pull the heads and check everything out. That's what I was leaning towards doing, but wanted to gauge the crowd to see if I was wasting my time.

RedXray

The 3500 Express vans didn't come with a LQ9. The only vehicles with the LQ9 are Escalades, Silverado SS, Silverado Vortec Max, Sierra Denali, Sierra Vortec Max. The Express vans came with the LQ4.

The Sloppy Stage 2 camshaft has a (recommended) 10.5 minimum compression ratio, the LQ4 has a 9.4 compression ratio. I've ran the SS2 in a LQ9 with the factory 10.2 compression and it was a good cam for my 4,400lb truck with 4.10 gears and a 3200 stall. Not saying you can't run the SS2 and have good performance but a camshaft that closes the intake valve sooner will build more dynamic compression delivering more bottom end torque.

The SS2 closes the intake valve at 42* ABDC. A cam like the Cam Motion "little chopper" closes the intake valve at 36* ABDC building a higher dynamic compression but has a lot of overlap at 11 degrees. I've ran both, the chopper has more bottom end torque than the SS2 but the SS2 had more upper RPM power and of course revved higher. The Summit Stage 2 Truck camshaft would be a good choice 218/227 .600/.600 112* this cam closes the intake at 39* degrees and has -1.5 degrees of overlap making it easier to tune and have a better idle quality. Whatever cam you go with you'll need an injector upgrade as the LQ4/LQ9 injectors are almost maxed out in stock form.