What is this?

[another69]

I picked up a mockup LS motor at the local wrecking yard. For $200 they gave me an aluminum 5.3. Not sure what it is out of, it is a longblock with no electronics or accessories. From what I can tell it looks to have DOD, front AND rear cam sensor, grey crank sensor, cathedral port heads, truck oil pan. I will try to post pics. Just curious if it is worth anything more than just a mockup motor.

[another69]

The heads are 243 castings and it looks like it must be gen IV, but why the rear cam sensor? Unless I am mistaken about it.

[csouth]

The motor is an LM4 or L33 depending on which vehicle it came from. It is a Gen3 5.3 as indicated by the rear cam sensor.

[another69]

Looks like the heads are basically LS6 heads without the sodium filled exhaust from what I can find online. Also, supposedly it can be bored out the same amount as an LS1/LS6 so I guess after some machine work and pistons it is basically an LS6???

I thought maybe it was an L33 Gen III, but the crank sensor is grey and it has DOD, so maybe Gen IV? I'm confused by the two cam sensors (front and rear). It really doesn't matter - I'm going with an LS3 - but maybe this motor is actually worth keeping. I really need to post pics, but it's not working through my phone. I didn't even know that these aluminum 5.3 motors existed...

[T_Raven]

You bought a good AL 5.3 long block for $200? That's a steal. Those heads go for around $400 all day long.

Could be a LC9 or LMG out of a Suburban. I can't keep track of all the variations though, so Idk how many AL 5.3 variants have DOD.

I would imagine a good long block would go for $1000-$1500.

I quoted fixing a guy's LC9 once for a bad DOD lifter. It was going to be something like $2000 in parts for GM's recommended fix, or a used engine was around $2000 locally.

I think it was going to be cheaper to swap in a low mileage engine, and I said I'd keep his core as payment. I figured I'd delete the DOD stuff and put it in my Camaro. He ended up selling the Suburban to someone that wanted to fix it.

I'm also pretty sure the gen IV 5.3 blocks can be sleeved with bigger, longer sleeves for building a big stroker.

http://www.erlperformance.com/produc...eeve-ls-block/

[camarodude87]

Yup was just going to say. Damn good deal. I bought a set about 4 yrs ago for 400 and they haven't gone down. If you want to ls3 and want to sell the heads I might be interested

[another69]

I'm not planning to do much more with this motor than mockup. Nice to know that it may be decent. I was surprised that it can be bored out as much as a 5.7!

I probably would sell the heads, as long as the sale was local.

Not sure on the condition of the motor though, I may pull the heads and the pan to see if there is a problem. I'm pretty sure there must be, because even the balancer is gone. It's just a long block with valve covers and exhaust manifolds