Gen III and IV GM Small Block V-8 Engines - Lego Engines

7. The factory roller lifters use plastic guide trays to keep lifters from spinning in place, yet make assembly quick. The head gasket is also made of multi layers of thin metal for a simple yet effective seal. The LS2 we built used the factory 243 casting aluminum heads outfitted with Manley intake valves, factory GM exhaust valves, and 190-psi valve springs. These heads are known to flow great and are held in place with 10 head bolts with five extra small bolts.

8. These engines use a molded plastic intake, but there are different styles depending on engine model. From left to right are: LS1, LS6 (LS6 has the inlet air-temp sensor on the side of the intake), truck intake (also known as an LQ9), LS2, and LS7. All the intakes are swappable except LS7. The LS7 uses a different mounting angle and has more square inlets compared to the more rectangular earlier engine, thus the LS7 and LS2 are referred to as Generation IV engines. One way to tell the intakes apart is the LS2 and LS7 have a 90mm throttle body with four mounting bolts while LS1, LS6, and truck intakes all use the 75mm throttle body with three mounting bolts. The LS2 and the LS7 intakes have the best airflow characteristics of the Gen III and IV engines, while the best torque ratings come from the truck (LQ9) intakes.

9. One benefit of the Turnkey crate engines is that the company changes all intakes to -6 fuel inlet lines. This is great for those swapping the engine into an older 4x4 since an aftermarket fuel system can be built. When assembling your fuel system it's recommended to run a fuel pump with 60-psi output to feed these fuel-injected engines.

10. The blocks have a bellhousing pattern nearly identical to the older classic Chevy V-8s. There is an extra bolt hole at the top of the block that many older transmission bellhousings do not have, and a hole on some older bellhousings like TH350 and TH400 at the 2 o'clock position that these blocks do not have. Some people add a tab to the bellhousing at the top to tie into the block, though most have found no issues with deleting these bolts. Many of the truck engines use an iron block whereas the LS1, LS2, LS6, and LS7 all come with aluminum blocks. However there is a new 6.2L truck engine known as an L92 that comes with an aluminum block.

11. In order to swap in the older transmissions, you may need this conversion flywheel kit that comes with all the mounting bolts, flywheel, and a spacer to attach the torque converter to the newer engine crank. There are also kits available to adapt a manual transmission to the back of these engines.

12. When junkyard scrounging, one difficult part to these engines is that block displacement identification can't be easily determined with the engine bolted to a transmission since the displacement casting is on the back of the engine. Here is "6.0L" cast into an aluminum block on the rear section of the block, so this means we are dealing with an LS2. If the casting were a 6.0, 4.8, or 5.3 in an iron block then it would be one of the truck engines, with the 6.0 being the most desirable for torque and performance. There is an aluminum block with 5.3L displacement from a Chevrolet TrailBlazer and Turnkey offers a 350hp version. An aluminum block with a 5.7 casting is either an LS1 or LS6, and a 7.0 casting in an aluminum block is the newer Gen IV LS7.

13. The Turnkey wiring harness is an easy way to swap an LS engine into your early-model truck or buggy. The harness comes ready to plug and play and simply requires 12V power, ignition, a tachometer, a fuel pump, and fans. The Delphi computer has been programmed with a Turnkey proprietary calibration and uses factory connectors for everything down to the electric fan controls. It is packaged in a marine-grade harness.

14. The harness plugs into the throttle positions sensor, idle air-temp sensor, MAP sensor, and idle air control on the intake as well as the knock sensor. The Turnkey engines use one knock sensor to tell the computer if the engine is detonating early and thus pulls timing. The truck, LS1, and LS6 blocks have knock sensors under the intake, while the LS2 and LS7 have them on the side of the block.

15. Four of the eight coil packs mount directly to the valve covers and are individual to each plug and cylinder. These negate the need for the classic distributor that mechanically distributes the spark to each plug.

16. When swapping the engine in place of an older Chevy V-8, you can simply use these motor mounts that bolt to the new engine mounting points but line up with the older-style motor mounts so the transmission doesn't need to be moved and the transfer-case location and driveshaft lengths can all stay the same.

17. Dealing with custom exhaust can be complicated with an engine swap, but there are many different manifolds and headers available for Gen III and IV blocks. Turnkey has both rear and center dump-block hugger units.

18. If you are really ready for some insanity under the hood, then give the guys at Turnkey a call. They have these engine available with packages including twin turbos and superchargers, not to mention custom cams and trick head work. If your checkbook can handle it, then power numbers between 330 and 775 hp are within reach. All engines are tested before they leave and can be rear-wheel-chassis dyno-tested once you have the engine installed if you want to bring your ride to the Oceanside, California, facility.