GM Performance Parts LS Engine - Cylinder Heads

One of the toughest jobs of an ls engine assembly is installing the damper, part number 12576652, which is a super-tight fit. We used a tool designed by Thomson Automotive. GM also has a tool for the procedure.
One of the toughest jobs of an ls engine assembly is installing the damper, part number 12
With the rods and pistons assembled, they were ceremoniously dropped into the cylinder block.
With the rods and pistons assembled, they were ceremoniously dropped into the cylinder blo
With the rods secured, the windage tray was set in place, but we didn't simply torque it down and move on to the next assembly step.
With the rods secured, the windage tray was set in place, but we didn't simply torque it d

The solution to the rod/windage tray interference problem is adding washers to the attachment studs to serve as spacers. it's all that is necessary to provide adequate clearance.
The solution to the rod/windage tray interference problem is adding washers to the attachm
Next up was the assembly of the rods and pistons. We used the cast ls7 pistons, part number 89018171, and exotic, super lightweight forged titanium ls7 rods, part number 12586258. With our 70cc cylinder heads, compression checks in at 11.0:1-perfect for a modern 93-octane street mill.
Next up was the assembly of the rods and pistons. We used the cast ls7 pistons, part numbe
Like so many other fasteners on the engine, the rod bolts are torque-to-yield. GMPP's Thom Bates snugged them down and checked the clearance between them all.
Like so many other fasteners on the engine, the rod bolts are torque-to-yield. GMPP's Thom

On LS engines with more than a 4.000-inch, or greater, stroke, the rod ends will likely interfere with the windage tray. Bates checked this by carefully rotating the crankshaft and noting whether the rods hit the tray. They did.
On LS engines with more than a 4.000-inch, or greater, stroke, the rod ends will likely in
The oil pump pickup was next. Because the engine can't be primed via a distributor hole like classic small- and big-block engines, it's important to get some oil into the pickup at this stage of the build.
The oil pump pickup was next. Because the engine can't be primed via a distributor hole li
We installed an F-car oil pan, part number 12558762, as it's the most "universal" of the various ls-engine production pans. in other words, it's the one that will retrofit into an older car with the least amount of hassle.
We installed an F-car oil pan, part number 12558762, as it's the most "universal" of the v

With the short-block assembled, the heads came next. Here, Bates drops on one of the ls7 aluminum heads.
With the short-block assembled, the heads came next. Here, Bates drops on one of the ls7 a
We used GM's ls-series lifter kit, part number 12499225, which includes 16 hydraulic roller lifters. They were doused in oil prior to installation.
We used GM's ls-series lifter kit, part number 12499225, which includes 16 hydraulic rolle
One of the unique features of the ls7 heads is offset intake valves, which necessitates correspondingly offset rocker arms, one of which is shown being installed here. Both the intake and exhaust ratios are 1.8:1.
One of the unique features of the ls7 heads is offset intake valves, which necessitates co

One of the most crucial inspections during the assembly is the squaring of the oil pan with the cylinder block. The best way to get it right the first time is running down the oil pan bolts, but leaving them a little loose; then, a straight edge is used to check that the pan and block are square. When everything lines up correctly, the pan bolts are final-tightened.
One of the most crucial inspections during the assembly is the squaring of the oil pan wit
The LS7 heads are masters of airflow. They're CNC-ported at the factory and flow approximately 350 cfm through 270cc intake ports. The intake valves are titanium and are 2.20-inches in diameter, while the 1.61-inch exhaust valves are sodium filled. They're all held at a 12 angle.
The LS7 heads are masters of airflow. They're CNC-ported at the factory and flow approxima
On all other ls engines, the lifters can be dropped in lifter guides that install two at a time. The provisions for extra head bolts on the lsx block, however, make that impossible. so, they're carefully inserted, one at a time, and held in place with lsx-specific guides that come with the cylinder block.
On all other ls engines, the lifters can be dropped in lifter guides that install two at a

Our engine builder, Thom Bates, took credit for pushing through at GMPP the ls7 intake assembly, part number 12568976, coming with the throttle body, fuel injectors and fuel rails pre-installed. it makes topping off the engine a much easier, quicker job.
Our engine builder, Thom Bates, took credit for pushing through at GMPP the ls7 intake ass
Assembly of the engine was wrapped up with the installation of the water pump, part number 89018053.
Assembly of the engine was wrapped up with the installation of the water pump, part number
On the superFlow dyno at Thomson Automotive, our lsx 427 kicked out an impressive 550 hp and 511 lb-ft of torque (sTP correction). This was with no tuning or external adjustment; the ls7 controller was simply plugged in and the engine was run on its preprogrammed tune. We were thrilled with results, as the performance was achieved with off-the-shelf catalog parts and a by-the-numbers assembly. Our engine was fuel-injected and used drive-by-wire electronics. GMPP has the necessary parts if you'd like to go this route. if you're going carbureted, you can use a regular, old throttle cable.
On the superFlow dyno at Thomson Automotive, our lsx 427 kicked out an impressive 550 hp a

Surprisingly, the ls7 coil packs don't come as an assembly, even though that's how they installed on the engine. The individual coils and mounting bracket must be purchased separately.
Surprisingly, the ls7 coil packs don't come as an assembly, even though that's how they in
One of the key enablers to making our engine project a turnkey affair was the use of GMPP's new, stand-alone ls7 controller, part number 19166567. it allowed the engine's wiring harness to simply plug into this ECM and-bingo-the engine was timed and tuned from the get-go. it could not have been easier to get the engine up and running.
One of the key enablers to making our engine project a turnkey affair was the use of GMPP'