While the new GM head gaskets we put on with the AFR heads had only a few thousand miles on them, these Cometic .040 gaskets would provide a more beneficial quench height and a slight bump in compression-perfect for heads/cam builds.... | 
...In addition, LS2-style 4-inch bore gaskets are required with the A&A/WCRCH Edelbrock heads. | 
The A&A Edelbrock 215cc heads were designed by West Coast Racing Cylinder Heads in Reseda, CA, originally for LS2s. However, A&A has since discovered these heads to make great power on the lesser-cube LS1s. Despite the name, these heads actually have a 212cc intake runner, as well as an 87cc exhaust and 64cc combustion chambers. As you can see,... |
...West Coast uses a CNC machine to cut its ideal shape and size from the meaty Edelbrock Pro-Port castings (PN 61989). The substantial wall thickness in these heads actually allows WCRCH to take the intake all the way to 245 cc for strokers and forced induction. Stock valve angle and geometry is retained, while still enabling 311/236 cfm flow at .600-inch lift (using a 4-inch bore). | 
Both Patriot Gold double valvesprings (PN 8401) and REV stainless steel valves came highly recommend from West Coast. The Patriot double valvesprings proved reliable up to .650-inch lift, and the accompanying Titanium retainers kept the valvetrain light for quick revving.... | 
...The REV valves are essential in providing the impressive flow and reliability these heads allow thanks to super strong swirl-polished 2.055 intake (PN SL1175) and 1.60 exhaust (PN SL1168) valves. |
The block surface looks pretty clean, so once the head bolts are cleaned out with a few shots of air to remove the coolant, the heads are laid on top of the gaskets. The ARP head bolts are treated to ARP assembly lube, and then the large bolts are step-torqued with 45, 65, and 75 lb-ft. The small bolts receive 24 lb-ft. | 
A&A recommended staying with the stock 1.7 ratio rocker arms since they are lighter than aftermarket variants and will work well with the cam. Teflon sealant is placed on the intake rockers to prevent oil from being sucked into the motor. The stock pushrods were also reused, which should help minimize valvetrain noise, but a hardened set will provide greater reliability. | 
Seeing as though the LS1 should be making more than 400 rear-wheel horsepower naturally aspirated, Kooks Custom Headers recommended a set of 1.75-inch long-tube race headers. These 304 stainless steel headers have a 3-inch spiked collector, which feeds an X-pipe with high-flow cats that necks down to 2.5-inches where it meets the Cat-Back. While not CARB-legal, they should free up a great deal of horsepower, and still pass the sniffer. |