Last month, I showed you the installation and testing of LG Motorsports' Pro Long Tube headers and a Stainless Works 3-inch exhaust system. These two components combined to free up nearly 30 horsepower and 30 lb-ft of torque at the rear wheels of our C6 project car, the Daytona 600. While that was a great start, I wanted more. And LGM had just the thing.
When performing a cam swap on an LS engine, most people choose to install ported stock or aftermarket cylinder heads at the same time. This is a logical plan, as the two components really need to complement each other for optimum performance. I had initially planned to go this route as well, but a couple of factors convinced me to take a more staged approach with D6C.
Truth be told, head availability was the largest factor in this decision. We all know that the market has an incredible number of LS cylinder heads available. So why not use one of them? Well, it just so happens that my favorite cylinder-head manufacturer is in the midst of developing an LS2-specific head to augment its existing, small-bore LS1 offerings. Intrigued by the possibility of breaking new ground, I decided that the large-chamber head for the large-bore LS2 might be just the ticket and definitely worth waiting for.
When I complained about this apparent setback to Louis Gigliotti, Jr., he had a completely different spin. "Don't sweat it-this is a good thing!" he assured me. "I've got a perfect little cam that is ideal for a stock LS2. It's emissions-friendly, makes huge torque, and is completely docile in traffic." Ever the cynic, I told him I was not interested in some limp-wristed smogger cam with an idle like a sewing machine. Louis assured me that I would be duly impressed with the idle as well.
Louis' advice was spot on. The LG Motorsports G5X1 cam does, indeed, seem to be the ideal cam for a stock LS2. There was a time, not too many years ago, that its 228/232-degree duration would have been considered pretty big for an LS engine. But in these days of 250-plus-degree duration cams in stock-displacement mills, the X1 is actually pretty conservative. With lift numbers of 0.588/0.574-inches, it is easy on the valvetrain, too.
The dyno sheet tells the tale:...
The dyno sheet tells the tale: D6C picked up 45 rwhp and 30 rwtq over the previous installation of the headers and exhaust. That puts the running total at 74 rwhp and 58 rwtq over our baseline.
So what's it like? Push the button to start the car (that still doesn't seem right), and it fires immediately, then settles into a slightly staccato rhythm at 900 rpm. And yes, Virginia, there is a pleasing lope-perfect for turning heads at the local cruise-in. Engage the clutch and roll out into traffic; you'll feel the additional torque instantly. The X1 makes a ton of grunt down low and on through the midrange, while enhancing the LS2's trademark top-end pull. When you drop the hammer, it's a whole new beast. This is no peaky, race-spec stick that only makes power above 5,000 rpm. It is totally tractable and would even work great in a daily driver, assuming you don't mind the extra attention your Corvette garners with its aggressive new sound. In short, the X1's a winner.
While a cam swap seems like an intimidating project, it really isn't beyond the ability of most DIYers, especially on an LS car. As with most things, a little patience and a lot of attention to detail will see you through. Included here are some of the highlights of D6C's cam swap. You're sure to find some useful tidbits, should you decide to tackle your own install.
Before you attack the cam...
Before you attack the cam swap, you'll need to remove the rocker arms and pushrods. This will allow the cam to be rotated, moving the lifters up into their retainers and permitting cam extraction. Start with the valve covers, then remove the bolts securing the rocker-arm base. The rockers and base can then be removed as one assembly, followed by the pushrods.
Removing the alternator will...
Removing the alternator will free up a lot of room on the driver's side, making life a bit easier.
You can now turn your attention...
You can now turn your attention to the front of the engine. Begin by removing the induction system. Here are the Vararam and the MAF on their way out.
In order for the cam to be...
In order for the cam to be removed, the radiator, radiator hoses, and A/C condenser need to be moved out of the way.
As D6C is a Z51-optioned car,...
As D6C is a Z51-optioned car, it is equipped with an external power-steering cooler, as well as transmission and engine-oil coolers that are internal to the radiator. The engine-oil cooler lines need to be disconnected, allowing the oil to drain. We'll get to the PS and trans coolers in a few minutes.
Remove the sway-bar bushings...
Remove the sway-bar bushings and allow the bar to hang from the end links. Here, the tie rods have already been disconnected in preparation for removal of the steering rack. All of this is done in an effort to gain the necessary space for fan removal and to improve overall access to the front of the engine.