Power Parts: New Forged Rotating Assemblies for Ford, Chevy, and Dodge V-8 Engines

There’s nothing new about reinforcing a stock V-8 engine’s internals to handle more power. Aftermarket forged crankshafts, rods, and pistons have been around forever. If you know exactly what to look for and have a sharp pencil and an insider’s knowledge of who makes parts for a particular engine family, you could cobble together just about anything. What’s relatively new is kitting together everything the amateur DIY engine assembler needs in one package, using all forged components for the greatest possible strength, balancing the assembly at the factory, putting them on shelves ready to ship, and pricing them affordably by manufacturing in bulk. We’ve seen a few companies do this but not on the scale that Scat Crankshaft has now managed.

For its part, Scat has done very little to draw attention to its new line of Modern Muscle rotating assemblies. In fact, Scat Crankshaft’s website doesn’t even mention them. We found out about them through Summit Racing while browsing their huge selection of stroker kits for late-model V-8s. (Modern Muscle rotating kits are available through other outlets, though.) We were excited to discover that Summit offers no fewer than 187 different fully balanced, fully forged stroker kits that cover just three late-model engine families: the Ford 4.6-liter Modular V-8, the Gen III/IV Chevy LS, and the Gen III Dodge Hemi. These are the most popular late-model fuel-injected engines being built today, and the time- and money-saving convenience explains our major source of excitement.

See All 5 Photos

Scat Crankshaft has been making forged crankshafts for over 50 years and operates a state-of-the-art machining operation in Oxnard, California. Crankshafts and rods are made of 4340 forged steel (rods appear to be I-beam or H-beam depending on application and source). Pistons in all Modern Muscle kits are forged full-floating units from SRP/JE, Ross, KB, Mahle, Diamond, or Probe and include pins and ring sets. Scat adds rod and main bearings from King, Federal Mogul, or Clevite 77, depending on the application, and all kits come fully balanced from Scat. All you need to do is have your block machined and drop the Scat Modern Muscle kit in. Let’s take a closer look at the options for Ford, Chevy, and Dodge.

See All 5 Photos

Ford Modular V-8, Starting at $2,674.99 (For 4.9L/297ci)

Summit Racing offers 14 Scat Modern Muscle rotating assembly kits for the 4.6-liter Modular V-8 (in 281ci, 297ci, and 300ci configurations). Note here that since the Ford 4.6 Mod cylinder block has limited internal dimensions and thin cylinder walls, there aren’t any stroker versions available for this engine family, and overbore is limited on the high side to .020 inch. The 14 Mod-motor variations offer special piston designs for standard compression or boost, and valve reliefs for two-, three-, or four-valve cylinder heads, so look the specs over carefully before ordering.

See All 5 Photos

Chevy LS, Starting at $1,839.99 (For 6.6L/403ci)

The lion’s share of SKU numbers in the Scat Modern Muscle lineup—141 kits to be exact—are for the Chevy Gen III/IV LS V-8. These are compatible with the gamut of LS Gen III/IV blocks, including 4.8-liter, 5.7-liter, 6-liter, 6.2-liter, 6.6-liter, and 7-liter blocks. Modern Muscle stroker kits can bring your block out to 5.9-liter (362ci), 6.0-liter (364ci), 6.2-liter (376ci), 6.3-liter (383ci), 6.5-liter (395ci), 6.6-liter (403ci), 6.7-liter (408ci), 6.8-liter (415ci), 6.9-liter (421ci), 7.0-liter (428ci), or 7.6-liter (467ci). Here, the starting size/family of your block matters (sorry! Can’t make a 467ci stroker from a 4.8-liter block), so read the fine print. The LS family offers particularly good value because Scat moves such a high volume of kits—as low as $1,839.99 for one that takes a 6-liter (364 ci) out to 403 ci!

See All 5 Photos

Dodge Hemi, Starting at $2,307.99 (For 6.4L/392ci)

Maybe the biggest news in the Scat Modern Muscle line-up is having 32 kits for the Gen III Dodge Hemi. There have been quite a few factory Gen III Hemis over the years, including the 5.7-liter (both early style and late Eagle style), 6.1-liter, 6.2-liter Hellcat, and 6.4-liter (both BGE and Apache variants), and the thing that stands out the most in the Scat lineup is the ability to take an ordinary 5.7-liter Hemi block (345ci) out to 392ci, and anything larger (aka 6.1-, 6.2-, 6.4-liter) out to as much as 426 ci. Mopar guys and gals will have a lot of fun sorting through all the possibilities. Scat has made sure to offer different kit versions for boosted and naturally aspirated configurations as well as in various overbores (just like its LS and Ford Mod kits), so start planning your combination today!

Sources

• Scat Crankshafts

• Summit Racing