After taking over the reigns at GMHTP I've been itching to start a new program to bolster excitement for the magazine. But what? We are already the presenting magazine for the biggest and most competitive LS drag racing event ever that draws the fastest cars in the country, and even have our own signature special edition Camaro (about to be released). As my turbine started to spin while discussing an upcoming budget LS1 stroker build with Contributing Editor Chris Werner, it dawned on me that even with a relatively modest budget, huge naturally aspirated power is possible using mostly the General's engineering. Simply put: you can make serious street-usable horsepower and torque using factory components. But how much? And how would you do it? As they say, there is more than one way to skin a cat, we thought this would be a better question for some of the best LS builders in the country.
As the compressor in my brain hit full boost, I realized what better way to pose such a question than to follow the lead of our SIM-compatriot Engine Masters (which recently allowed LS motors into competition), and have a dyno competition. But as 99 percent of all forum "bench racing" is done on a chassis dyno, it would seem to make more sense for us to use this format--with the vehicle of choice being a late-model GM EFI of course. Furthermore, we wanted to get away from the more high-brow crowd, and keep the rules simple, therefore more difficult to manipulate--that way the winner is decided only by who builds the most powerful motor based upon a stringent set of rules.
And what pray tell would the rules be, you ask? Well, as my initial goal was to bring out the sickest street motors possible on a relatively modest budget, I decided the first stipulation would have to be a factory 6.0L block with no deck spacers or resleeving the cylinders. These cylinder casings are abundant and cheap, especially the iron truck blocks, and limit bore size to a little over 4.0 inches. By design of course, this allows use of the extremely frugal, factory square-port L92 head that has proven (in its short existence) to be capable of serious power potential. Making this factory casting a spec part, obviously serves the purpose of reducing cost not performance. Stroke and cubic inch limitations seem unnecessary, given the block's sleeve length--most competitors will be running either a 4.00 or 4.10-inch stroke, which would put cubes at around 427 cid max. Because of cost and availability, an OEM intake manifold seemed the logical choice as well.
As these are to be street-going, pump gas motors, a True Street-style cruise would be a must as would wet sump lubrication and hydraulic roller cams with an rpm limit for dyno testing. Knowing the exciting new innovations by Mast Motorsports and Comp Cams with variable valve timing, and in the spirit of GMHTP, we wanted to make room in the competition--so the use of factory PCMs is mandatory (and VVT is allowed). Each car is expected to be fully tuned before it arrives, and retuning will only be allowed after the first and second pull, following the street cruise. As the winner will be decided based upon not only peak horsepower and torque, but average power as well, the seat-of-the-pants feel (important to a street car) will be preserved. Builders will have various aspects to display their talents including the cam design, head port work, machining and ring seal, valvetrain dynamics, header choice, PCM tuning, and intake choice (or design).
What Do You Think?
If you would like to show your support for this event, or have any suggestions, feel free to contact GMHTP Editor Scott Parker via email (Scott.Parker@Sorc.com).