I have a 02' LQ4 which has been bored .065 over so running all LS3 internals. Pistons, rods, even crank (58x), as well as heads (0821) and an LS3 intake.

From my understanding I have to relocate the knock sensors from the valley cover to the side of the block, correct? Question is with the crank change to 58x, and LS3 front cover (pn# L200010106) which relocates the cam position sensor, which valley cover should I go with: LS2, LS3 or can I reuse the LQ4?

 

Only the early style will fit. There are two different ones depending on the PCV setup, but both will have the knock sensor towers. Basically reuse the one you have, but you should plug the knock sensor holes so trash doesn't get in there...

 

Cool, thanks! So upgrading to the newer style with the breather spout isn't actually necessary?

 

Depends on your emissions laws and if you'd rather run VC breathers than a PCV system. The later cover is better for PCV but both can work...

 

The knock sensors can stay in the valley-I believe they work better there anyway.

I suggest you go with the LS6 valley cover with the integrated PCV stuff.

 

Paul, will the early knock sensors work with the 58x wheel & ECM? I (like the OP) was under the impression they needed to be swapped to the later style...

 

Good question!! Another thing I need to know...

 

I gotta find this EFI book I have that has this info......

 

I don't believe so, there are adapters to adapt the LS1 harness to accept the LS2 and newer knock sensors.

 

Yeah, but isn't that made for people that are swapping to the later (58x) engines and ECM's while keeping their harness intact? The only experience I have is with a carb'ed LS1. Nothing EFI yet, but I do read a lot. And no, I didn't sleep in a Holiday Inn last night...

 

The 24x knock sensors are single wire, resonant type.

The 58x knock sensors are two wire flat response type.

You'll need the two wire type. They bolt on the outside of the block with a through bolt. Cavity A, blue wire, signal. Cavity B, gray wire return.

You'll need to install dummy 24x knock sensors in the valley to get the valley cover to seal around them. OR you can somehow fab up a closure for the knock sensor holes.