Carp

Guys need some advice. I have a 2010 suburban lifted on 35’s (measure 33”) with 3.73 gears (4.56 in the near future). Truck is approaching 200k and leaking oil from every gasket. I got a great deal on an ATK075 gen 3 short block with is a 5.3 bored to 5.7 with forged rods and pistons. I plan to have the machine shop change to a 58x wheel and tap the block for the knock sensors. With 317 heads it’s 9.8 compression but I ran across a deal on 243’s rebuilt with .660 dual springs. Puts me around 10.5 compression. Plan to keep vvt and run the tsp 212/218 cam. I’ll build the motor on my stand and I know I’ll need a few gen 4 set ups as far as timing set up and timing cover. Will I run into any issues where I shouldn’t do this route? Would I do better running felpro .041 head gaskets as apposed to ls9’s to improve quench? Looking to tune for 89 octane as this isn’t an all out race build just looking to do an improved rebuild.

G Atsma

Where would the .041 HG's put your compression? You MIGHT be OK with 89 octane, but first see where the compression will end up.

Carp

I’ll go from around a 10.57 on LS9 gaskets and 10.9 on .041 gaskets. Being a big heavy truck I’m more towards low rpm torque tires which I know compression will give me... only worry is the price difference around me for 93 and it would appear gas will be going up a good bit. If I was looking for all out performance I wouldn’t hesitate running 93.

Carp

Other option would be to run 317 heads with .041 head gaskets for around a 10:1 compression which would be fine.