One might think that pushing 1,000+ horsepower out of a Supercharged L5P Duramax diesel engine after taking off all of the stock emission parts and still claiming that the engine will run emission-free is impossible, but not for Gale Banks. He has done it before with turbocharged setups and is still doing it with his new supercharged creation that was on display at the 2021 SEMA Show earlier this month.
Based on an L5P “as shipped from the Duramax assembly line,” out of Moraine, Ohio, Gale Banks starts by taking off just about the whole front of the engine, the top of the engine, and most of the rear external parts of the L5P Duramax. This teardown process is the start of what will become a dual inlet front-feed supercharged Banks LP5 Duramax diesel.
Digging Deeper Into The L5P Duramax Diesel
To make sure a full counterweight can be placed on the crank at the rear, the timing trigger is moved to the front of the crank and becomes 10-percent smaller. Setting right in front of that is a massive supercharger pulley that should turn the supercharger with close to a 4-to-1 ratio or spin the supercharger at about 18,000+ RPMs while the diesel crank spins at 4,440 RPMs.
Banks and Comp Cams worked together to grind a .500 lift cam, which is about .100-inch bigger than the previous .400 lift cam. According to Banks, he has been working hard with GM to have the new cam and his set to be placed in the Duramax engines from the assembly line.
The new cam setup includes better-designed springs from Comp Cams that have the correct top and bottom diameter to fit the stock seal and alignment piece at the bottom of the spring and fit the stock retainer at the top of the spring. The springs were needed when the .500 lift cam came into play. New pushrods were designed by Trend for a bigger diameter wall thickness, with a one-piece rocker arm ball cup. And although all new bolts are used to clamp down the heads, they are identical bolts to the stock L5P Duramax bolts. Banks sees no need to move to a stud design for the heads until the stock bolts show they can’t hold up to the pressure any longer.
“Charged Air-Cooler” Two Purposed Supercharger
The billet intake that Banks creates leaves plenty of room for options when it comes to power adders. In the video, Banks shows off the Charged Air-Cooler intake that can expect a supercharged setup, an outboard turbocharger and intercooler setup, a nitrous setup, or a whacked-out combination of all three.
S&S 50+ psi fuel injectors are used, but as Banks puts it, “they might become 100 psi.” Keep in mind this is all while staying within the Euro 3 clean emissions requirements.