photos by: the author
Sleeper Status Hits the Street… Briefly.
Sometimes, things just don’t go as planned. Between mechanical failures and well, life, projects can easily fall off the wagon. As much as we’d like to say we’re immune to such circumstances, sadly, we too are susceptible to the curse of a stubborn project car and the rigors of simply keeping up with the trials, smiles and tribulations of life.
For those scratching their heads and wondering what the heck happened to Project Sleeper Status, our Buick Regal GS project car, we’ll spare you from the hardship portions and fill you in on the roadblocks currently preventing our next dyno and track thrashing.
If you recall from the past stories, we’d added a slew of ZZPerformance (ZZP) bolt-on parts to sink our full-weight Regal GS solidly into the mid-13s at 100 mph on crappy California 91-octane gas. For those keeping track, the ZZP bolt-ons were worth an additional 53whp on the dyno and an improvement of 1.01-seconds and 7.5 mph at Sacramento Raceway over our stock baseline—our best pass was a 13.67 at 100.04 mph on a 2.05 short- time.
What helped us so greatly at the track? How about some well-placed ZZP mods that started with a free-flowing 3800 cold-air intake, along with a set of stainless steel long-tube headers and a 3-inch catless downpipe with a matching 3-inch cat-back exhaust. Additional goodies included a ZZP PCM 1.0 reflashed ECU and a move to ZZP’s modular supercharger pulley system with a 3.4-inch pulley—the results from these bolt-on bits were nothing short of spectacular as the Regal finally had some lungs.
Truthfully though, while the bolt-ons made a huge improvement, they were just the foundation for much, much more. That’s right, the real gains were yet to be found since they were lurking under the valve covers, in porting the blower, and by addressing the knock retard with cooler IATs.
After some strategizing we felt that our next best move was to dive inside the engine and swap the puny stock cam with the infamous ZZP X-P Hot Cam Package to unlock the full potential of our L67 motor.
Diving Inside for even Bigger Gains
As any W-body fan can attest, you can only make so much power with the stock bumpstick before it becomes the limiting factor. So with an eye for increased efficiency, we contacted ZZP and after explaining our goals for the car, they recommended their X-P Hot cam, one of the most aggressive cams available for the GM 3800 motors that still plays nice with the stock heads.
How hot? ZZP claims a 40-55hp improvement depending on your supporting mods thanks to aggressive specs that measure 212/225 .520/.536 – 116 using 1.6 rockers measured at 50-degrees. The aggressive cam is not only great with a stock or modified blower, but it also plays nicely with nitrous.
Along with the new cam, we also sourced 140-pound Comp Cams valvesprings, titanium retainers, new ZZP LS7 lifters, 7.00-inch pushrods, a Rollmaster Double Roller timing chain, an extra thick front cover gasket and a machined oil pump cover, also from ZZP, to clear the thicker double timing chain.
“The stiffer valve springs necessitate a Rollmaster Double Roller timing chain, which in turn requires a machined oil pump cover, and an extra thick (some people double stack stock gaskets—ED) front cover gasket to clear the wider chain,” Steve Hickman from ZZPerformance said.
“The X-P Hot cam is so much more efficient that you can get away with an even smaller 3.25-inch pulley on the same fuel without additional knock retard, which isn’t possible with the stock cam,” Hickman explained.
The last piece of this round’s puzzle was a Northstar throttle-body as well as the ZZP Northstar throttle-body installation kit with a CNC-machined adapter plate and a modified LS6 MAF kit from ZZP that replaces the stock 69mm throttle-body with a larger 75mm unit and a bigger, more freer-flowing MAF to further uncork the inlet side of things.
Much like the rest of the build, we used a local friend’s shop to dive into our W-body. After some careful consideration we decided the best method was to go ahead and drop the motor, transmission and K-member out from the bottom (using a two-post lift) since once the unit was free, it would allow unabated access to the cam and valvetrain components. Truthfully, it tacked on several hours of removal time on the front-end, but saved us at least double that amount of time in the long run.
The installation was lengthy and involved, but we took our time and all appeared to be well…at first. Once the last bolt was tightened and the fluids checked, with a turn of the key the L67 V6 snapped to life with a choppy idle and a new rasp—she sounded angry.
After some break-in miles we made a few passes up a straight stretch of lonely road that revealed a noticeable increase in midrange punch with a robust top-end pull to the now increased redline—the Regal felt exceptionally stronger the last 1,000 rpm of the tach.
We were looking forward to hitting the track the following weekend for new and improved times, only, that’s not how it played out. Instead, on the short drive back to the shop we heard a faint mechanical sound, as if something lightweight, thin and metal was lightly contacting something stationary. Was it the timing chain contacting the machined cover? Was it something in the valvetrain? We coasted the car back to the shop and after firing it up to get a better listen with a stethoscope while it idled, it suddenly died.
A quick hit of the starter revealed the engine no longer wanted to turn over, so we busted out a breaker bar to see if the motor could be coaxed into turning over only to find she was stuck unless we exuded serious amounts of force, at which point she’d turn over. A deeper look at the oil didn’t immediately reveal metal shavings, and removing the valve covers didn’t tell us anything like a stuck valve or the like—our best guess, it unfortunately spun a rod bearing…maybe? We’ll be cutting the oil filter open for a closer inspection before diving deeper into the motor to see if we’re better off getting a used takeout replacement or fixing the original motor—we’ll keep you posted.
Listen to that lope! It’s the only video we captured before its early demise…but don’t worry, she will see the light of day again.