{"id":43772,"date":"2020-10-05T12:00:08","date_gmt":"2020-10-05T16:00:08","guid":{"rendered":"http:\/\/www.dodgegarage.com\/news-api\/?p=43772"},"modified":"2024-03-25T11:22:14","modified_gmt":"2024-03-25T15:22:14","slug":"gen-iii-hemi-engine-quick-reference-guide-part-i","status":"publish","type":"post","link":"https:\/\/test.api.dodgegarage.com\/news\/how-to\/2020\/10\/gen-iii-hemi-engine-quick-reference-guide-part-i.html","title":{"rendered":"GEN III HEMI®<\/sup> Engine Quick Reference Guide Part I"},"content":{"rendered":"\n

The Beginning: <\/strong>
2003-2008 5.7L HEMI\u00ae<\/sup> V8<\/strong><\/h1>\n\n\n\n

It\u2019s hard to believe but the current generation HEMI\u00ae<\/sup> engine has\nbeen out for 17 years, and in that time, well over a million units have rolled\noff the assembly line. The production GEN III HEMI engine has seen a variety of\ndisplacements from 5.7L to 392 cubic-inches. In its most lethal stock form, the\nsupercharged 6.2L HEMI engine in the Dodge Challenger SRT\u00ae<\/sup> Demon has well over 800\nhorsepower on pump gas and comes with a full factory warranty. With literally\nmillions of GEN III HEMI engines out in the wild, you can now find these engines in\nplenty of salvage yards and on Craig\u2019s List relatively cheap. Like any engine\nfamily that\u2019s constantly evolved, there are better years and applications in\nthe way of blocks, heads, intakes and other items. One good thing: All GEN III\nHEMI engines share the same bellhousing bolt pattern of the Chrysler LA or\nMagnum style small block (273, 318, 340, 360). <\/p>\n\n\n\n

\"HEMI<\/figure>\n\n\n\n

Regardless of which GEN III HEMI engine you go with for your\nresto-mod project, Mopar\u00ae<\/sub> and many other leading aftermarket companies have the\ncomponents you need when swapping this 21st century V8 into your 1960s or \u201970s\nMopar car or truck. There are many standalone tuning products available to\nmake your modern HEMI swap an easy plug and play. So, before you head out in\nsearch of a GEN III HEMI engine to install in your Mopar project, check out our handy\nspotter\u2019s guide to help you ID all the various versions of this legendary 21st<\/sup>\ncentury HEMI engine. We\u2019ve broken it up into a\nfour-part series that includes the original 5.7L, its bigger 6.1L and 6.4L siblings, and the wild child fire-breathing supercharged 6.2L SRT Demon,\nSRT Hellcat Redeye and SRT Hellcat engines. <\/p>\n\n\n\n

\"RAM
2003.5 Dodge Ram 1500 with optional HEMI(R) power.<\/figcaption><\/figure>\n\n\n\n

2003-2008 5.7L HEMI <\/strong><\/h2>\n\n\n\n

The first GEN III HEMI engines appeared back in 2003 in the Dodge\nRam 1500, 2500 and 3500 trucks. It displaced 5.7 liters (345 cubic-inches for\nyou old-school fans). The 5.7L HEMI engine replaced the tried-and-true 5.2L (318) and\n5.9L (360) Magnum engines whose roots share some of Chrysler\u2019s LA small block\narchitecture along with AMC cylinder head magic. Unfortunately, the Magnum\nengine family couldn\u2019t keep up with the increasingly tough emission standards and\nmileage requirements automakers were facing at the start of the 21st century. In its early form, the 5.7L HEMI engine made 345 hp and 375 lb-ft of torque in\nRam trucks and 335 hp in the Jeep\u00ae<\/sub> Grand Cherokee, Dodge Durango and Chrysler\nAspen SUV models. By 2005, the new LX platform of RWD and AWD vehicles had come out,\nwhich included the Chrysler 300C, Dodge Magnum R\/T and Dodge Charger R\/T. The\n5.7L HEMI engine was rated at 340 to 350 horsepower depending on the package and thus reignited\nChrysler\u2019s dominance in the high-performance sedan market. Even though the\nChallenger SRT8 came out in 2008 with its 425-horsepower 6.1L HEMI engine, fans would\nhave to wait until the following year (2009) for the R\/T model with the new VVT\n5.7L HEMI engine that we\u2019ll get into during Part II of this series. <\/p>\n\n\n\n

\"Charger<\/figure>\n\n\n\n

ENGINE BLOCKS AND ROTATING ASSEMBLY <\/strong><\/h2>\n\n\n\n

To identify the displacement GEN III engines, \u201c5.7\u201d is cast on the\ndriver\u2019s side of the block above the oil pan rail and are painted black. These\nearly GEN III HEMI engines are fairly plentiful in most salvage yards and are pretty inexpensive.\nAll 5.7L HEMI engine blocks are cross-bolted (like the original 426 HEMI engine) and have a\ndeep skirt to provide rigidness for the crankshaft when it spins at high engine\nspeeds. One of the biggest questions we see is regarding transmission\ninterchangeability and, thankfully, the GEN III HEMI engine has the same bellhouse bolt\npattern as any Chrysler small-block. That means anything from an old-school\nthree-speed 727 or 904 TorqueFlite\u00ae<\/sup> to the current 8HP70 eight-speed TorqueFlite.\nIf you want to row your own gear, there\u2019s also numerous manual transmissions\nthat will bolt-up behind the modern HEMI engine. The 5.7L HEMI engine block can be\nsafely bored to 0.030\u201d oversized during the rebuilding process and there are\nnumerous companies offering forged pistons in a variety of compression ratios. The casting number is located on the front of\nthe block on the driver\u2019s side and can be either 53021319AG or 53021319CB. The production 5.7L crankshaft is made\nfrom cast iron and can be reused in many applications. However, if you\u2019re\nbolting on a supercharger or turbocharger, you\u2019ll need to go with an aftermarket\nforged rotating assembly that not only includes the crankshaft, but also\nconnecting rods and pistons. Too much boost will damage the production rotating\nassembly over time, so do it right the first time. A 6.1L crankshaft shares the same\nstroke and makes a nice forged upgrade for a pre-Eagle (2003-2008) 5.7L HEMI engine. <\/p>\n\n\n\n

\"HEMI<\/figure>\n\n\n\n

CYLINDER\nHEADS<\/strong><\/h2>\n\n\n\n

The GEN III HEMI engine cylinder heads are cast aluminum and feature a twin-plug\ndesign for better efficiency. Ironically, twin-plug HEMI engine heads are nothing new\nas Chrysler used this technology 50 years ago in Pro Stock and eventually on Nitro\nengine applications. Twin-plug aluminum HEMI engine cylinders heads are still used\ntoday on virtually all Top Fuel Dragsters and Funny Cars, including the 15,000\nhorsepower machines that propel Dodge\/\/Mopar DSR drivers Leah Pruett and Matt\nHagan to well over 300 mph in three seconds within 1,000 feet. When using GEN\nIII HEMI engine cylinder heads, there are many versions to choose from, but be aware of potential interchangeability issues. Early 5.7L HEMI engine cylinder heads that have\nracked up 100,000 miles or more can suffer from dropped valve seats, so make\nsure to have the heads inspected and refreshed. You should also know the early\n2003 to 2008 GEN III HEMI engine cylinder heads come in right and left versions with\ncasting numbers 53021300AJ (right) and\n53021300BA (left). As you can see in these images, the stock production\nGEN III HEMI engine cylinder head’s intake and exhaust ports can outflow many modified\ncylinder heads.  <\/p>\n\n\n\n