When you start to make more power with the stock engine you run the risk of having an engine failure. The Stock LE9 engine found in the Slingshot does not seem to take the same power as the older LE5 2.4L found in earlier GM vehicles like the Pontiac Solstice or Saturn Sky. On supercharger or turbo kits we recommend building the engine for reliability when you reach the 300hp level at the rear wheel. So, if you are looking at exceeding stock power or just want the peace of mind knowing that your engine can take the abuse you are going to give it, our DDMWorks built engines are the best option. We have designed our DDMWorks built long blocks for performance, strength and reliability in your Slingshot and have been building the 2.4L since 2007, and have the most experience with engine builds specifically for the Slingshot. After all of the builds we have done, we know the best parts to give you a engine that you can install and expect a long life from, along with high performance.
We are happy to now offer 3rd gen blocks as a build option. What are 3rd gen blocks? The original LE5/LE9 engine found in the Slingshot has its block cast by a process called "lost foam". During this process a styrofoam engine core is placed in sand and molten aluminum is poured into the mold were the aluminum replaces the styrofoam. If you look closely at the side of the stock engine, you will see the surface looks like styofoam because of this process. This lost foam process allowed GM to cast a complicated engine relatively easily, however it was found to cause a weak point that can allow small cracks to form in the block. This led GM to improve the block during the next revision with a sand cast version of the block. The new 3rd gen sand cast block gives a more uniform finish in the block and is less prone to cracking found in the lost foam castings. GM didn't just stop there though with that improvements to this block, they also added more material to the inside of the block to strengthen the block internally. The most important upgrade however came to the cylinder bores themselves. The stock LE5/LE9 has floating cylinder bores, which mean that the top of the cylinder bores are not secured to the block, the new 3rd gen blocks added material at the top of the cylinder bores to bridge and stabilize the tops of the bores. This bridge also increased the amount of aluminum around the top of the bores to help strengthen the cylinders even more against higher cylinder pressures found with high horsepower builds.
There is a lot that goes into these new engine builds, we start by removing the cylinder head and inspecting it for any damage. The cylinder head is then completely dis-assembled by removing all valves, valve springs, guides and retainers. The 3 mating surfaces are machined for a nice smooth surface, the cylinder head is thoroughly cleaned, pressure checked and then re-assembled with new and improved bronze valve guides, viton valve oil seals, 8 new intake valves and 8 new exhaust valves.
To build the block, we either start with your stock block, a 2.4L LE5/LE9 block or a 3rd Gen Ecotec block core and then completely disassemble and fully clean it. The deck of the block gets fully machined to give a smooth mating surface for the cylinder head, the rotating assembly is then balanced, the crank journals are polished and the short block is then re-assembled, checking for tolerances along the way. With the short block assembled we then install the cylinder head on the short block using the new parts listed below -
- Full GM Main Bearings
- Full GM Rod Bearings
- GM 2.4L Head Gasket with improved cooling passages
- GM Rear Main Seal
- GM Oil Pump/Timing Plate Cover Gasket
- Qty. 20 GM Main Bolts
- Qty. 10 GM Girdle Bolts
- ARP Head Studs
- Forged Rods (option of Molnar or Carillo)
- Custom Wiseco Pistons with Ceramic coated tops, Slick side coating, wrist pins, rings, locks @ 88.5mm bore
- GM Timing Chain
- GM Timing Chain Tensioner
- GM Upper Timing Chain Guide
- GM Slack Side Timing Chain Guide
- GM Tension Side Timing Chain Guide
- GM Valve Cover Gasket
- GM Water Pump
- GM OEM Oil Pump/Timing cover
- Cylinder head work - Inspect, Pressure Test, surface, Install 8 new intake valves, Install 8 new exhaust valves, 16 new Viton Valve seals and bronze valve guides.
With this build you end up with an engine that can take the power you want to put down with the Slingshot reliably, in a package that comes to you ready to install in your ride. Have any questions about the build or other options? Give us a call or send an email and we will be happy to point you in the right direction for the power and budget you have.

WARNING:This product can expose you to chemicals which are known to the State of California to cause cancer and birth defects or other reproductive harm.
For more information go to www.P65Warnings.ca.gov. This product has not been submitted for California CARB approval. Off-road use only in California and states adopting California emission standards.