- Location
- Grand Junction, CO
I found this engine locally for $800, a guy had bought a older Chevy truck with this LQ4 swapped into it and it had (apparently) been a recent build, with only 12 miles on it... but things went south with the engine. It has some awesome upgrades, like the A-Team Short Fab Intake with massive injectors, 92mm Holley Sniper throttle body, etc. It has the factory 317 6.0 heads, but that's about all that was known. The PO didn't know anything about the build, camshaft, internals, etc. He claimed it had been ran on a dyno and made 500 HP at the crank. 
🇺🇲
It was running and I was able to listen to it before it was pulled and it sounded healthy, but terrible.... a definite knocking sound, not a rod but more cam like. The PO believed it was a cam bearing and I agreed with the assessment. We made a deal and he started pulling the engine.
Once it was home, I started tearing it down. The PO kept the valve covers, the valley pan, flex plate and had unbolted the intake. Before pulling anything, I grabbed the rockers and 1/3 of them were LOOSE, not a little.... but a lot. Way more play in them up & down then there should be. That was the first sign of issues.
Someone used a lot of silicone on the gaskets... which isn't really needed. I thought that was odd. I used hardly any on my L33 build and it has zero leaks. There was also a lot of trash and junk sitting in the external head bolt valleys.
I believe its a 2006 block, based in the numbers cast into the passenger side of the block. Looks like 'F236' with the last number designating the year.
Was able to get the lifters out (all but 1, its STUCK!) and inspected them.... again, about 1/4 of the lifters had the rollers chewed up. There was a definite cam issue going on! The cam looked to have been walking around and tearing up the edge of the lifters.
Pulled the heads off and was surprised that there wasn't much crosshatching on the cylinders. There is no cylinder ridge at the top, but I'm not surprised as these blocks don't wear much from my experience. Pistons look new-ish, but I have to question the '12 miles' on this build. The pistons to look like standard dished LQ4 pistons.
The timing chain was super loose, had WAY more play in it than it should. The torx bolts for the cam retainer plate were stupid tight.... I took a torch w/ rosebud tip to the bolts and block hoping the heat would loosen them up. Got 2 out of 3, then the last one stripped out. I ended up having to weld a nut to the bolt to get it out!
I started to pull the cam out and it got hung up within the first 2-3 inches.... and I could hear something loose, rattling around. I looked into the block and could see a cam bearing floating around on the cam, getting hung up on the other bearings! It took some effort to get the cam the rest of the way out of the block. Once pulled, I saw that the lobes were pretty messed up.
The cam had a part # printed on the end... 31824100. Which a quick Google search turns this up.... it was a Brian Tooley Racing Stage 3 cam!!! 😭 - https://briantooleyracing.com/btr-camshaft-gen-3-4-truck-stage-3-v2-btr31824100.html
So here's where we're at now.... I need to pull the crank, rods & pistons tomorrow.
The plan is to have a machine shop go thru the block, clean it all out, install new cam bearings and go from there. The cam and lifters went into the trash, as did the one-time-use head bolts.
I would like to make some upgrades, the 317 heads have pretty large chambers, so lower compression. If I can find some decent 4.8 or 5.3 truck 243 or 706 heads to bump up the compression. I wouldn't need flat top pistons if I do that. I may keep & run the aluminum intake, since I have it, but it's probably not the best option for an engine that should be focused on torque.
Not sure what cam I'll run, but want something better than stock for sure. Perhaps another Brian Tooley Racing Truck cam?
I'll finish the engine off with either a Camaro water pump, balancer & accessories for a little more clearance over the truck parts at the front of the engine.
500 HP will be more than enough, but with a head upgrade bumping up the compression a little more, the right camshaft, 1.8 ratio rockers & that intake.... it should be getting close to the 550 HP range. 🤪😍
🇺🇲It was running and I was able to listen to it before it was pulled and it sounded healthy, but terrible.... a definite knocking sound, not a rod but more cam like. The PO believed it was a cam bearing and I agreed with the assessment. We made a deal and he started pulling the engine.
Once it was home, I started tearing it down. The PO kept the valve covers, the valley pan, flex plate and had unbolted the intake. Before pulling anything, I grabbed the rockers and 1/3 of them were LOOSE, not a little.... but a lot. Way more play in them up & down then there should be. That was the first sign of issues.
Someone used a lot of silicone on the gaskets... which isn't really needed. I thought that was odd. I used hardly any on my L33 build and it has zero leaks. There was also a lot of trash and junk sitting in the external head bolt valleys.
I believe its a 2006 block, based in the numbers cast into the passenger side of the block. Looks like 'F236' with the last number designating the year.
Was able to get the lifters out (all but 1, its STUCK!) and inspected them.... again, about 1/4 of the lifters had the rollers chewed up. There was a definite cam issue going on! The cam looked to have been walking around and tearing up the edge of the lifters.
Pulled the heads off and was surprised that there wasn't much crosshatching on the cylinders. There is no cylinder ridge at the top, but I'm not surprised as these blocks don't wear much from my experience. Pistons look new-ish, but I have to question the '12 miles' on this build. The pistons to look like standard dished LQ4 pistons.
The timing chain was super loose, had WAY more play in it than it should. The torx bolts for the cam retainer plate were stupid tight.... I took a torch w/ rosebud tip to the bolts and block hoping the heat would loosen them up. Got 2 out of 3, then the last one stripped out. I ended up having to weld a nut to the bolt to get it out!
I started to pull the cam out and it got hung up within the first 2-3 inches.... and I could hear something loose, rattling around. I looked into the block and could see a cam bearing floating around on the cam, getting hung up on the other bearings!
It took some effort to get the cam the rest of the way out of the block. Once pulled, I saw that the lobes were pretty messed up.
The cam had a part # printed on the end... 31824100. Which a quick Google search turns this up.... it was a Brian Tooley Racing Stage 3 cam!!! 😭 - https://briantooleyracing.com/btr-camshaft-gen-3-4-truck-stage-3-v2-btr31824100.html
So here's where we're at now.... I need to pull the crank, rods & pistons tomorrow.
The plan is to have a machine shop go thru the block, clean it all out, install new cam bearings and go from there. The cam and lifters went into the trash, as did the one-time-use head bolts.
I would like to make some upgrades, the 317 heads have pretty large chambers, so lower compression. If I can find some decent 4.8 or 5.3 truck 243 or 706 heads to bump up the compression. I wouldn't need flat top pistons if I do that. I may keep & run the aluminum intake, since I have it, but it's probably not the best option for an engine that should be focused on torque.
Not sure what cam I'll run, but want something better than stock for sure. Perhaps another Brian Tooley Racing Truck cam?
I'll finish the engine off with either a Camaro water pump, balancer & accessories for a little more clearance over the truck parts at the front of the engine.
500 HP will be more than enough, but with a head upgrade bumping up the compression a little more, the right camshaft, 1.8 ratio rockers & that intake.... it should be getting close to the 550 HP range. 🤪😍
