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Looking at the dyno numbers, this first camshaft gave up a little torque below 2,600 rpm, but added an astounding 76 hp at 5,800 rpm!

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The LPE baseline in this configuration used the traditional and more lenient aftermarket correction factor and generated 313 hp and 345 lb-ft of torque, which is right in line with the factory specs assuming a 5 percent differential between the two correction factors.

There may even be the advantage of a few extra ponies with an iron block compared to the aluminum version.

If you compared the horsepower peaks, this little cam was worth 65 hp over the stocker while also adding 21 lb-ft at peak torque.

Keep in mind that all we’ve done is bolted in a conservative camshaft, a set of Comp valvesprings, and a set of 131/44-inch headers. This time, LPE pulled out a much more aggressive mix of lobes that most certainly will qualify it as “fairgrounds lumpy.” This is LPE’s GT1-1 cam that bumps the duration at 0.050 up to 229/242 degrees of duration while the valve lift skyrockets to 0.631 inch for both intake and exhaust. While this is a big cam for a little 325ci engine, it also promised some healthy horsepower numbers.

It’s no secret that the new Gen III small-block is the hot engine in the performance aftermarket.

Everyone has been stuffing cams and manifolds into 5.7Ls and some have even experimented with those expensive Gen III-based 427ci engines.

After several power pulls, it was obvious that we had traded low-speed torque for horsepower since the big cam created quite a torque dip between 2,000 and 3,500 rpm where the motor lost as much as 50 lb-ft at 2,400 rpm. The power almost overlapped the original stock engine’s level between 3,000 and 4,200-then the big cam began to make some serious noise.

From 4,400 to 6,800, this little small-block rocked!

Next month, we’ll add a set of LPE CNC-ported heads, and one of Comp Cams’ LSXtreme intakes to see where those mods take this little 5.3. Power Add-Ons The production 5.3L SSR engine is a virtual clone of the iron block version except for its aluminum block, yet GM rates the SSR 5.3 at a healthier 300 hp and 330 lb-ft of torque using the SAE production car correction factor that employs a higher inlet air temperature (and other changes) that explains why the SAE corrected numbers are always lower.

LPE’s Rob “Dyno Bob” Vanderhart bolted the bone-stock 5.3L SSR engine to the dyno along with a complete accessory drive on the front of the engine as well as the equivalent of a muffled exhaust system connected to the stock iron exhaust manifolds.

This is still using the stock 1.7:1 Gen III shaft rocker arms.

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