We had the car and the parts, and TT Performance in Passaic, New Jersey, offered to do the install for GMHTP. TTP is a full-service install and tuning facility staffed with nice guys who know their way around LS engines and the vehicles they power. And with proprietor Matt Sorian's tuning background with HP Tuners, the all-important tuning aspect would be well covered.
Follow along as TT Performance transforms our stock-engine LS1 into a powerful street car.
Driving Evaluation
A couple of weeks after TTP finished with the Z, Chris Werner and I made a trip out to Pennsylvania's Pocono Raceway. It wasn't driven on-track, but after several hundred miles of street and highway duty, stop-andgo traffic, etc., I got a pretty good feel for the new combination.
The heads and cam from Patriot work very well. The heads flow lots of air and allow tons of top-end power, especially since we put this cam in at the same time.The cam is fine for a daily driver-there is just a hint of surge at very low rpm, similar to many LS1 cams on the market. But it is more than worth it when the tach swings past 6,000. It loves to pull, and the 243 heads love to breathe. Matched up with the COMP lifters and pushrods, we've got a solid combo. No problems to date.
So far I'm very pleased with the Hooker exhaust system. The headers installed and fit well, there didn't seem to be any problems with the Y-pipe or exhaust, the tips look great, and there is a terrific, raspy rumble when this thing runs. So far, there have only been two exhaust clunks over very big bumps at high speed, which is to be expected. No problems.
Another Racetronix fuel system install, another hassle-free high-hp-capable LS1. This really is a nice pump and wiring setup. With the big 60-pound injectors, Matt at TTP had to work a little harder with the part-throttle tuning, but they drive and react like the 28s-but instead of a nearly maxed-out duty cycle, they are only at 55 percent. No problems.
The SLP airlid fits very well, and it seems like the oil pump is doing its job. While I don't have anything quantifiable to report on the Zex plugs or Torco oil, the gas is getting lit up, and the engine is getting lubed just fine.
I was hoping the 60-pounders wouldn't result in a lazy tune, but Matt Sorian's custom tune is a good one. Driveability with this cam is fine; it doesn't stall, starts and idles well, and the WOT air/fuel ratio is spot-on. No problems.
So there it is. I spent just over five grand for all these parts and 81 hp and 40 lb-ft at the wheels,and my car needed $537 worth of maintenance parts to get it up to par. You can get away with spending only around $4,800 for that power gain. Not too shabby.
 ...The flow sheet sent out...  ...The flow sheet sent out with my heads revealed 300 cfm on the intake and 213 cfm on the exhaust, both at .600 lift- pretty impressive for $1,095. |  Patriot even spec'd out a...  Patriot even spec'd out a cam for use with its heads: a 225/229 duration at .050, .581/.591 lift, and 114 LSA stick. "We listened to customer feedback when designing this cam," Gunnar states. "Customers with the 243s and Stage 2 243s wanted a more aggressive grind than the 226/226 cam we'd done before. This 226/232 makes more power and more rpm, and is great for stock-cube LS1s with Patriot heads and bolt-ons." This cam should make good power and still be very driveable with a tune. |  A full Hooker exhaust system...  A full Hooker exhaust system will usher the spent fumes out. Here are the headers, 1.75-inch long-tubes that have been ceramiccoated. |