There is a lot of interest in the LS world nowadays. The LS is rapidly becoming the king of motors, surpassing the Honda B and K series or the 2JZ as the most popular motor to be swapped into imports. GM is also making some killer cars that use the LS platform as their OEM engine. With its compact dimensions, light weight and potential for big power in a dimensionally small package the LS is a very appealing platform indeed. With help from some of our partners like Eagle Rods and King Bearings, let us show you how it’s done!
One of the biggest markets where the LS excels is the drift market. In drifting a wide powerband is important. Drifting is also very brutal on equipment and a large displacement LS is under less stress than a highly boosted turbo 4 or 6 cylinders. Guess what going to last longer under hard use. For this next build, we are going to build a naturally aspirated LS3 for use in a Nissan 350Z Pro-Am drift car. For a Pro-Am car, budget is important so we decided to build a motor with good durability but a lower cost for items where we thought we could get away with it.
The LS3 displaces 6.2 liters or 376 Cubic inches with a 4.06″ bore and a 3.62-inch stroke. A drift car needs decent bottom-end torque and a wide powerband and the easiest way to do this is to increase the stroke. For this reason, we selected Eagle Crank Part Number 442740006100. This crank uses a 4″ stroke to get our displacement up to 414 cubic inches or 6.8 liters. When using a standard OEM LS block as the basis of your build, it is best not to exceed 4″ of stroke. This is because the cylinder skirts of the bores on the LS are on the short side and at past 4″ of stroke the piston skirts poke out of the bottom of the bores. This causes the pistons to become unstable in the bore at bottom dead center and you can see odd wear marks on the bore and on the piston skirts due to this.
We ordered our crank with a 58 tooth reluctor for new LS engines like the LS3. LS engines used in drifting tend to spin the reluctor on the crank causing crank angle sensor sync problems. Eagle welds the reluctor onto the crank to prevent this saving you from having to have this done.
The Eagle crank is machined out of a tough non-twisted 4340 forging. 4340 is a steel alloy with high amounts of nickel, chromium, and molybdenum. These alloying agents make steel that is highly fatigue and impact resistant making 4340 one of the best materials to make a crank out of. The crank is rated at 1500 hp so it will be more than strong enough to handle our naturally aspirated build. To finish our crank we got Eagle’s optional ESP Armor surface finishing. ESP Armor gives the parts a chrome-like super slick finish that is so smooth cracks have a hard time propagating in it, greatly improving fatigue strength. The super slick finish also reduces friction and windage losses which increase power.
For Rods, we chose Eagles heavy-duty H-Beam rods part number CRS6125O3D2000. The rods are rated at 1300 hp, this is much better than the standard Eagle rod which is rated at 750 hp. Drifting is tough use and if you can go stronger without a weight penalty, always side with stronger! The stock LS3 uses a rod length of 6″ but we opted to use a longer 6.125″ rod to reduce our piston speed and stress on the engine.