GPI - L83 Drop-In Piston / Connecting Rod Package
Bulletproofing the L83 for Boost
The LT series GM engines are incredible powerplants as designed – however unlike their predecessor (LSx) – the LT’s commonly rebel when power adders such as superchargers, turbos, and nitrous are added.

unlike the LS – the LT’s commonly rebel when power adders such as superchargers, turbos, and nitrous are added.
The LT powerplants have several weak links when boosted:
- the unique piston and ring land design which was intended for naturally aspirated duty is subject to failure under even minimal detonation.
- preignition has been associated with various detergents found in certain motor oils which become emulsified resultant of the fuel being sprayed under pressure into the cylinder creating unintended combustion
- We have found ring end gaps as small as .008 which will certainly butt together causing cylinder, piston and ring failures when subjected to increased heat and cylinder pressure.
- We have found L83 connecting rods during engine upgrades on stock forced induction engines which were slightly bent even though they were still asymptomatic.
Overcoming Limitations
Understanding these limitations – and because GPI strives to provide the best combination of power and reliability for our clients – we have worked with Diamond Racing and Callies to offer a no rebalance, standard bore, stock compression, drop-in solution for the Gen V 5.3 liter L83 engine.



What does this mean for you? No machine work and no balancing needed. This is a complete drop-in assembly that can be installed while the engine is still in the car!
The Solution
Gwatney Performance is proud to present a Complete Drop-In Piston and Rod solution for the Gen V L83 (5.3L) Engine! This package is designed specifically for boosted 14+ Silverado / Sierra / Tahoe / Yukon.
By working directly with Diamond Racing and Callies, and were able to get the exact same bobweight as the factory piston / rod assembly, and due to the heavier weight of the factory assembly – we were able to build an extremely robust piston and rod package.



This kit is designed to support 900+HP applications and is the perfect match for your forced induction L83!!
Results?
Reliable and consistent high horsepower Gen 5’s! Here is a recent build with these our very popular Gen 5 LT pistons. This is a street car, so power and boost levels are fairly conservative.
- GPI LT Drop In Pistons & Rods
- GPI LT Cylinder Heads
- GPI LT Camshaft (SS1)
- G1Pro Sheet Metal Intake Manifold w/ GPI Port Fuel Injection System
Questions?
Give us a call at (501) 985-4947 or email [email protected].
To apply for a dealer wholesale account – visit our GPI Dealer Application Page.
Good quality
Took awhile to get here but product is good
Very Happy with all the pistons, rods, bearings! Best bang for your buck! I’m building an l83 with a magnuson supercharger in my 71 C10! Definitely putting this to the test!
Wow, this company went above and beyond my expectations! Super nice, very knowledgeable, I definitely recommend GPI and look forward to sending in my heads to y’all ASAP!
Couldn’t be any happier came faster than I thought and glad I listen to all my turbo truck friends guiding me they say they love them besides the quality the price is amazing if I build another gen v these will be the brand to go with without a doubt