Building a Drift Spec LS3

The Eagle rod uses a two-piece forging. This means that the rod is forged in two pieces with the cap forged separately.  This allows the rod to have the metal’s grain flow in a circle around the big end bore.  With this forging method, there is less distortion of the rod’s big end under load and superior strength of the part, especially fatigue strength. The entire surface of the rod is machine finished.  This ensures consistency in dimensions and weight.  It also creates a smooth finish with no irregularities where a crack inducing stress riser can form. After machining, the rod is subjected to shotpeening.  This is where the rod is bombarded by hard steel shot at high velocities.  Shotpeening helps refine the grain over the surface of the rod, creating a finely grained compressed layer of steel where cracks have a hard time propagating.  Shotpeening causes the fatigue strength of most steel parts to rise by over 100%.

If you look in the machined valley of the “H” you will notice a rib at the base of the valley, this rib increases the fatigue strength of the rod’s beam.  The oiling holes for the piston pin are drilled upwards at an angle towards the pin.  Putting two smaller holes at the bottom makes a much stronger part than your typical single bigger hole at the top of the pin bore. The piston pin bushing is tough silicon bronze, one of the most wear-resistant bushing materials available.

Rod bolts are the most critical part on the connecting rod, no expense was spared here.  Eagle usually uses genuine ARP 2000 3/8″ rod bolts on all of their rods but the heavy-duty Eagle rods use a 7/16″ bolt.  These rod bolts have a tensile strength of over 230,000 psi, many times stronger than the factory bolts.

We turned to CP for a set of their forged pistons, part number BLS1131-STD, designed specifically for stroked LS3’s.  Our CP pistons are forged from tough low silicon 2618 alloy. 2618 is a tougher alloy than high silicon alloys like 4032.  The main disadvantage to 2618 is that it expands more with heat so it needs to run a bigger piston to wall clearance.  This can result in noise, piston slap, and greater wear.  CP has largely made this a moot point with their advanced piston skirt cam profiles which allow tighter clearances and reduce noise and slap.  Notice that the piston pin hole is moved up into the oil ring groove a small amount to accommodate the longer rod and the 4″ stoke. Although this looks weird we have done this many times and have never had a problem with oil ring wear or excessive oil burning.

Our piston have a dome which gives us a final compression ratio fo 13.2:1. This is an E85 or race gas only compression ratio.


  1. Mike, great information! I was wondering to build this engine as you did on your channel but running off regular premium gas, what modifications would I need to make? How much power loss could I expect as a result? I’m eager to get similar horsepower at the rear wheels. But I’m sure the current setup wouldn’t allow for premium gas.

    1. Price out all the parts including the block and every peice needed to have a plug and play motor. Multiply that number by 2.5 and it will be actual cost.

      1. Actually, it’s a lot less than that. The parts are expensive. Labor and machining are about $4000, WPC of most parts is about $2700

        1. Price out all the parts including the block and every peice needed to have a plug and play motor. Multiply that number by 2.5 and it will be actual cost.

          Mike has $4000 plus $2700 parts = $6700

          Pete’s rule of thumb parts [$2700] x 2.5 = $6750
          Not too far off .
          then there’s all the other stuff needed to have a runnin motor….Like Fuel ,Ign systems , ETC

          1. There is no way the parts on this motor are only $2700! That is just the cost to WPC treat them.

  2. hi mike, love your videos and information. can you please tell me the make and part # of the wrist pins you used in this build. thank you for your time.

    1. Mike said the labor, machining and WPC of most parts was $6700. That doesn’t include the cost of any of the parts. I would bet another $15000 in parts, my guess is $22000 to make it plug and play.

      1. We notice some blocks are very thin on one side due to this. Some blocks are OK. Its just a cuation for people buying new blocks to do builds like this.

  3. hello mike i am from holland and i want to build this engine for my volvo amazon 1966 project car
    can i run this engine with 98 octane pump gas without race gas
    or do i need to use another compresion ratio for that
    i am planing to use it for street and strip use
    hope you can help me

  4. Hi Mike. Love the content just one simple Question, Did you have the 6.2 Ls Bored over to a 6.8 liter for The Stroker kit or the stroker kit gave it the displacement to a 414 cubic inch?

    1. It’s done with stroke, aluminum LS blocks can’t be bored out much, we said exactly what we are doing in the third paragraph, don’t be lazy, read!

  5. Hi Mike. What oil weight do you recommend for drift ls3 with tight bearing clearances. Is 15w50 will be good choice or its too heavy ?
    Thank you

Leave a Reply

Your email address will not be published. Required fields are marked *