Meet the L83 – the new 5.3L GM small block truck engine with the same horsepower and more torque than a stock LS1.

The future is looking pretty bright for GM enthusiasts, if you ask us. Thanks to a recent release on GM’s website, we’re finally getting a look at the power numbers and stats of the engines that will likely become a “swapper’s delight” in the not too distant future – the EcoTec3 line up in Sierra and Silverado.   

The 4.3L EcoTec3 V6 engine makes essentially the same power as the LS 5.3L engines. Isn’t technology great?

Let’s start with the V6. Base model Silverado and Sierra 1500s will come with a 4.3L FlexFuel V6 called the “LV3” which shares all the same technologies as the V8s. With variable valve timing, direct injection, and an 11.0:1 compression ratio the LV3 makes essentially the same power as most of the LS 5.3L truck engines. This little beastie produces 285 horsepower and 305 pound feet of torque on gasoline, but if you put in E85 output jumps to 297 horsepower and 330 pound feet of torque.   

The second engine option is the EcoTec3 5.3L FlexFuel engine that has been given the designation of “L83”. The all-aluminum engine displaces 325 cubic inches, with a bore of 3.78” and a stroke of 3.62” – the exact same bore as the LS 5.3L, and the same stroke as every LS engine except the 4.8L and LS7. Compression ratio is a sky-high 11.0:1 to match the direct injection, and redline is set at 5,800 RPM. If you’re expecting more power ouf of these new engines, you won’t be disappointed. Both horsepower and torque are way up for the Gen-V 5.3L mills. On gasoline the L83 makes 355 horsepower and 383 pound feet of torque, but if you run it on E85 and you’ll be rewarded with 380 horsepower and a whopping 416 pound feet of torque. Think about it – that’s more power than a stock LS1!

We still don’t have any numbers for the 6.2L EcoTec3 engine, but the release does give us a bit more info. The 376ci engine will be called the “L86”, and will have a big bore of 4.06” and the same stroke as the L83. The L86’s compression ratio is up slightly at 11.5:1, and the redline also jumps slightly to 6,000 RPM. These are promising specs, and given the impressive power of the 5.3L L83, you can bet that that the big-dog L86 is going to have even more power and torque.

Keep it tuned here for more details as they become available!

All three engines share the same technologies and promising stats. Comparing the engines side by side, what stands out most to you?