Wehrli 01-04 Chevrolet 6.6L LB7 Duramax S300 Turbo Install Kit (No Turbo) - Bronze Chrome

If you're looking to swap your stock IHI turbo for a larger Borg Warner S300 frame turbo on your 2001-2004 6.6L LB7 Duramax Silverado or Sierra, this install kit from Wehrli Custom Fabrication is what you'll need. This kit is designed to make that transition smoother, handling the plumbing and intake modifications so you can focus on the turbo itself. It's a comprehensive package that addresses the airflow path from the turbo all the way into the engine, aiming for improved horsepower and efficiency.

Wehrli has put together a solid package here, starting with a fabricated aluminum intake system that uses a 4-inch diameter pipe and a heavy-duty sheet metal air box with a high-performance dry filter and pre-filter cover. The intercooler piping gets an upgrade too, with 3-inch diameter mandrel-bent aluminum tubes for both the hot and cold sides. A key piece is the upgraded 3-inch fabricated billet Y-bridge, which replaces the restrictive stock part to help maximize airflow into the engine. The kit also includes high-quality stainless steel braided oil feed and drain lines, routed from the main oil galley on the engine block. The downpipe is a 3-inch unit with a high-temp ceramic coating and a V-band connection, designed to mate directly to your existing exhaust front pipe without needing any cutting or modifications. They've even included a driver-side transmission dipstick tube relocation bracket to make installing the downpipe easier.

This kit is built to accommodate a variety of popular turbo sizes (sold separately) that mount to a T4 fabricated steel pedestal. It's compatible with Wehrli's 2-inch high-flow stainless steel up-pipes. Remember, the turbo itself is not included, so you'll need to source that separately. If you're not buying a Borg Warner turbo directly from Wehrli, be sure to provide the details of the turbo you plan to use so they can ensure proper fitment for your kit. Lead times begin once they have the turbo needed for mock-up and fabrication.