Correct. The XER273 is a pretty good 'off-the-shelf' cam for a build such as yours. If your proposed LQ9 is actually getting 60-61cc heads, you're looking at 11-11.2:1 compression so plan to fill up on premium octane only and be sure of your tune.

To take full advantage of the heads and cam, I highly recommend looking into the Trailblazer SS intake manifold, throttle body and a good exhaust. A standard truck intake with stock exhaust manifolds will hold a set of TFS heads back like the Hoover dam.

If it were my truck, I'd have the XER273 custom ground on a 112+2 instead of a 114+2.

 

why a lq4 instead of a lq9?
yeah i def plan on running only 93 or better
what does the +2 mean adds 2 degrees more advance in the timing i guess

 

More than likely the LQ4 will be cheaper.

It means the intake lobes are ground 2 degrees ahead of the exhaust lobes. By bringing the lobe separation angle and intake center line down to 112/110 instead of 114/112, you will help increase the cylinder pressure and low end torque of the XER273.

 

do you think i could get the xer273 o a 110 lsa or would it even be worth it

 

Unless you find the off-the-shelf version considerably less expensive, I'd get the custom ground cam made.

 

You have better head options with the LQ4 since most everything is geared towards the smaller combustion chambers of the ls1/ls2 heads, assuming you don't want your compression over 11:1. The only real advantage I see with the LQ9 is better quench.

 

quench area = power

 

well im pretty sure that im going to end up with a LQ9 what is a good price on them ive found a couple for around $1000 up to $2500

 

Quench distance is measured by finding the piston-to-deck clearance and factoring that into the head gasket thickness when compressed. Quench distance has nothing to do with compression ratio.

 

flat top - better quench.