Modifying a Corvette Grand Sport - LS is the Best Chevy V8

The LS engine platform is the best engine GM has ever had. I know there are some die hard small and big block guys out there that think otherwise - but follow along and I will show you what none of those engines could ever accomplish.

We are going to start with a new 2011 GS, while it is not a 2012, it is a brand new left over. The first dyno run was done with 800 miles on the clock. I first used this car to do some air filter testing. The outcome of that testing will have to be for another story. This particular GS was an A6 automatic. The car runs fairly well, but I did have a check engine light when I first picked the car up. A quick check of the gas cap fixed that. So now it was time to pump the tanks dry and fill up on some Sonoco 94. I do this because every brand of gas has their own blend and since we are always testing Corvette parts, I like to use the same fuel so I know that at least every tank is very close to the same fuel makeup. With the tanks full of the Sonoco, I headed out to one of my trusted dynos. We typically use several different dynos depending on what we are trying to do. This time, it was just to get some good base line numbers, so we used a Dynojet 248.

Once the car was strapped down it was time to hook up the scanner and get to work. The first step was to make a first run and see what the GS could do. The first pass was good with a 383.82 hp and 380.65 ft/lbs of torque. Next, we reset the fuel trims to see what she would do. I made 5 runs after this, trying to get the car back to the same engine coolant temp before each run. The best the car could do was what it did in the first pass, the closest to it was 383.06 hp but 377.35 ft/lbs of torque. Now this is not enough difference that even the best of any driver would ever feel and it falls in the +/- accuracy of the dyno. So with data in hand, it was time to head back to Zip to add some parts.

We have several power packages that we offer, but they are a far cry from the typical parts you see advertised in the marketplace. The first item that we added was our stepped Kooks headers. These headers were designed originally to compete in the World Challenge for Banner Engineering. We were building differentials for them and a phone conversation ended up with George from Kooks Custom Headers building Zip a special set of headers. From there, the headers were used for some mock up on the then-new LS7. They did so well in the midrange that we decided to go ahead and have our own header made by Kooks. We have since made some ever so slight changes and we are also using them on the LS3 engines and modified LS2's.

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Source: Corvette Magazine

Submitted by Phil Ellison