STOCK VS. DRM MODIFIED LS1
"DRM’s chassis dyno baseline recorded with a bone stock LS-1, six-speed ’98 Vette.It’s 383 package (tube headers, CNC cylinder heads, performance camshaft, tuning, and related modifications) netted gains of roughly 100 lb-ft of torque and 100 hp! Note that the altered engine produced 380 lb-ft by 3,200 rpm and that the stock motor didn’t reach its peak of 310 until 4,100.  A street racer’s delight." That’s roughly 450 hp and 470 lb-ft of torque at the crank! (Assuming a 15% power loss through the 6-speed’s drive train)
…"some impressive levels have been attained thus far. The accompanying chassis dyno sheets from DRM are a good indicator. This vehicle is said to pass federal emissions requirements and retain all OEM emissions systems…and cranks out 400 lb-ft and 380 hp at the rear wheels!" "This is the most we’ve been able to achieve to date [at press time] and represents a lot of work in the heads and exhaust system"… "the emissions certifiable 383 reckons to become a popular benchmark for the LS1."

EXHAUST MODIFICATIONS FOR LS1
…"Header upgrading shows gains. Stainless 409 steel set DRM design is reportedly worthy of 10 hp and 10 lb-ft over stock"… "They feature thick flanges, ceramic coating inside and out, and retention of all stock emissions components."

CLUTCH MODIFICATIONS
"All the torque you can make won’t find the ground without the proper clutch. In cooperation with Centerforce clutches, DRM has developed this single-mass package that’s reportedly 20 pounds lighter than the stock unit it replaces. DRM claims quicker acceleration and a holding force capable upward of 600 horsepower"

 WHO THE PLAYERS ARE
"To date the ‘traditional’ aftermarket has taken a hands-off approach to this engine. Maybe they’re waiting for a market demand to develop. It wouldn’t be the first time. Meanwhile, look who’s doing the pilot, after OEM work now…and who’s not. Do you find it curious that while LS1 engines are sitting comparatively idle on the dynos of traditional aftermarket parts makers, the Rippies and Lingenfelters of the industry, are looking for more midnight oil? Give Lunati and Hypertech credit too. We’re talking serious investments in crankshaft forging dies, piston tooling, and related performance hardware and software."