I have a 2003 6.0 Lq4 bottom end. How would a set of stock 2007 Non-DOD heads from a 5.3 do with this combination. I am debating on doing a cam and springs from comp cams maybe or just putting an lq9 cam in that I already have. Would these heads benefit from a mild port and polish job. My hope is that the smaller chamber of the 5.3 heads will make up for the dished pistons in the LQ4 block to get the compression up some more. Its a daily driver with an auto not going to the track or any type of racing. Just looking for more punch than a 5.3 can offer me.

Short crew 4wd dropped w 3:73's

 

I think the 07 5.3 had 243s? You'd want the 862/706 5.3 heads. Zippy just did this build on an LQ4, he simply added bigger valves and I think he really likes it.

 

What type of 5.3 do I need to be looking for to find the 706,862 casting numbers

 

anything 06 down should be the 5.3 heads. BTW, those heads you have now, the 243 aka ls6 heads will also do very nice on the lq4. It wont raise the compression as much as the 5.3's but it'll flow better

 

Guess I need to go pop the hood and check it right quick it's an old body style 2007 got it really affordable so I could not argue and it only has a notch over 12K on it. It's a Zcode 5.3

 

if its the 07 classic it may actually have the 5.3 heads, I'm not sure if they switched over for the whole 07 model year or just the nnbs

 

Leaving the heads stock valves and all im hoping it should be ok. I sold the heads off of the 6.0 to a customer who came in the shop and needed some.

 

My 5.3 has the 706 casting heads on it. Do they need anything done prior to putting them on or are they fairly good as is. On the flip side are there any other heads that would work reasonably well and get the compression up a bit and flow well that are on the affordable side. I'm looking at existing stock heads that are on other OEM LS motors that do not need to be modified prior to installation yet will still yield good results on a daily driver.

 

ls6 heads $450 from Patriot.

 

Guess I'm just going to suck it down get the ls6 heads and see what comp has to say about cam specs based on the truck and how Im going to use it. Thanks a bunch