As has been said time and time again, weight and horsepower are interchangeable. Save 50 pounds, and it's like adding quite a few extra ponies. The burden of mass becomes even more of an issue when the weight is rotating at speed. And while it is enough to spin items like wheels, axles, differentials, and driveshafts rather than just to accelerate them along, it takes even more energy to get your much-faster-spinning engine internals, flywheel, and clutch up to speed--energy that can better be used accelerating your car forward instead. Without a doubt, savings in this area are of paramount importance. SLP Performance Parts of Toms River, New Jersey offers solutions for your stick-shift 1998-2002 LS1-powered F-body or 1997-up Corvette. Its high-strength steel billet flywheel saves a full 8 pounds over the 24-pound stock cast-iron unit. Aside from being lighter, it is also stronger and of better quality than the original item. Brian Reese, Chief Engineer at SLP, explains the result. "I can tell you, for one thing, the rev-ability of the motor is a lot better with this flywheel. Any time you shave any kind of weight off of the rotating assembly, especially something as significant as eight pounds, you are going to be able to tell. The acceleration of the motor has a definite seat-of-the-pants feeling that it's better."
And if you're looking to upgrade your clutch at the same time, SLP offers a high-performance package that provides up to 25 percent more holding capacity than stock. "If you buy our flywheel by itself, you're free to use your own clutch, whether it's a stock unit or some other aftermarket one. Or, we sell the full-on clutch package which includes the flywheel and everything else you need for an improved bite."
On an SLP F-body test vehicle already equipped with nothing more than a few bolt-ons and a set of slicks, a full tenth of a second of quarter-mile ET was slashed away when these items were installed. Of course, more can be expected on a heavily modified car. The full clutch package also has additional benefits. "A lot of times when you are powershifting or doing some hard driving on even a modest car, you feel a little bit of slip before engagement. That's not the case here; you're going to get solid engagement with our improved clutch. And while it's slightly harder to push the pedal, it's more of a sporty feel--not as sluggish as the stock setup. That's actually the comment we get most, customers are most stoked about the way the clutch feels." Note that if you have a 2002 F-body, you already have this much-improved clutch (it is a GM part after all, thanks to SLP's tight relations with the General), but fear not--you will still be able to benefit from the flywheel.
Follow along as we hit the highlights of SLP's installation of its full clutch and flywheel package on a 1999 Firebird Formula. Expected installation time is 4-7 hours for the do-it-yourselfer, a small sacrifice for such an improvement in performance and feel.