Im helpping my father put together the parts for a LQ-9 build. It will have all brand new rotating assemblyand bored .30 over. We will top it off with stock 243 heads and a TBSS intake with 35lbs injectors. He would like to keep valve train stock except for trunion upgrade. He would like to find a cam factory cam that he can stay with in range of factory springs and lift but get better low end torque. So to make a long story short which cam would stay in the factory spring specs and provide good low end?

If it matters he will have a tune done and he already has Gibson shorties , K&N intake and borla cat back. Ive been trying to convince him more lift could net more power but he seems to be stuck in his ways about factory spec valve train....

 

Just put a 212/218 or a 204/210 cam in it. All great low end torque very cheap if you find a used one. Assuming they are the yellow springs an not a regular spring

Or an LS6 cam if you can find it cheap

 

A LS6 does not have good low end torque

 

I would throw in a set of hardened push rods while your in there. And a set of new springs.

 

Im trying to convince of that but he's stuck in his ways

 

this build makes me sad

 

He said a cam within factory spring rating. Also i can name a truck with less motor that beat his personal best with a LS6 cam vs a 212/218 an a 220/220

 

Trust me I know I've been trying to convince him more lift and better springs but he set in ways. He thinks GM puts things together best and he's got the thought that factory parts last better than everything rest. I will work on convincing him more.
My build I went with lq9 243 heads, Harland sharp, PAC 1518 spring and custom cam with TBSS intake . I'm trying to convince him the same or close

 

Imho Any aftermarket cam on factory springs is not a good idea. I used a .560 lift on factory ls6 springs and had a spring break. Luckily the valve didn't drop onto the piston and it only bent a pushrod. Also, I helped a buddy replace his ls6 in his vette due to a factory spring break on a factory ls6 cam.....