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2001 Chevy Camaro Z28 Heads, Headers & Exhaust Upgrade - Budget Badass
Thrifty Heads/Cam/Bolt-On Goodies Pick Up 81 Rear-Wheel Horses
Feb 1, 2008
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2001 Chevy Camaro Z28 Heads, Headers & Exhaust Upgrade - Budget Badass
Patriot Performance offers several quality LS cylinder heads at a great price. Gunnar Bowlin of Patriot Performance believed Patriot's LS6/LS2 heads would add a good amount of power, and the price was right.
These 243s contain a lot of technology for the price. They are CNC-ported and feature a 64cc combustion chamber and stock 2.00/1.55-inch valves. Patriot Gold valvesprings are included, as is a new set of GM head bolts for the install. A comparison with a stock LS1 head (below) reveals the chamber work on the Patriot heads (right)....
...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 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 will usher the spent fumes out. Here are the headers, 1.75-inch long-tubes that have been ceramiccoated.
The Y-pipe ...
And the Cat-Back exhaust system, utilizing an Aero Chamber muf-fler, a 3-inch intermediate pipe, and dual 2.5-inch tailpipes. This is a 16-gauge, fully mandrel-bent aluminized steel system that shows itself off with two handsome "dual-pipe" tips. All installation hardware is included.
GM Performance Parts hooked us up with a host of replacement parts. Patriot recommended early LS1 graphite head gaskets for better quench; with them the LS1's compression ratio will be around 10.7:1. Instead of going with a pricier ouble-roller, we got only a new timing chain. The coils and wires are in bad shape, and we'd been fighting misfire codes for some time. The new GM pieces will solve that problem. Final assembly pieces include valve cover gaskets, a crank bolt, a crank seal, and a timing cover gasket (not shown).
I turned to SLP for a great-fitting airlid that will add some power, and a heavy-duty LS1/LS6 oil pump to protect the soon-to-be high-powered LS1. This high-performance oil pump is a great idea if you plan on taking the stocker off.
COMP Cams, FAST, and Zex are supplying hardened pushrods, roller lifters, 60- pound high-impedance injectors, and performance spark plugs.
GMHTP has had excellent results from Racetronix fuel systems, and will be using its '99-02 plug-and-play F-body system in tandem with the 60s to provide more than enough fuel for our needs.
Once we get to TTP, Jason Partyka and Matt Zorn get to work on the Z28.
Because a major heads/cam/bolt-on project really needs the engine torn down, the exhaust system, manifolds, fuel rails, intake, valve covers, rockers, lifters, pushrods, coils, plugs, cooling fans, and radiator are all removed.
To remove the heads, three 15mm power-steering bracket bolts need to come off the driver-side head, as do two 15mm ground-wire bolts on the back of the head. Ten large and five small head bolts are removed from each side using a 15mm socket on the big ones and a 10mm on the small ones.
The serpentine belt comes off and the water pump is removed by pulling six 10mm bolts. Next, a three-jaw puller is used to remove the crank pulley. Ten 10mm bolts are pulled to yank the front cover. There are eight in the front, and two come up through the oil pan.
Eleven 10mm bolts free the oil pump. Three 10mm bolts are removed to take off the timing sprocket, and it and the old chain are removed. Four 10mm bolts for the cam retaining plate come off, as does the plate.
To slip the old cam out, the TTP crew works together to gently lift up and angle the condenser. The "correct" procedure is to disconnect the condenser and remove it completely; though TTP's method can result in a broken line, if you are gentle with it, you can get away scot-free and won't be recharging the A/C system to boot. Still, attempt at your own risk.
The stock camshaft is slowly removed.
The Patriot cam is cleaned up and coated with assembly lube. Matt lifts up on the condenser again, and Jason slips the new cam in. This step requires a steady hand and patience as the stick is gently turned/pushed into place.
The cam retaining plate is slipped back on, and the four bolts are torqued to 18 lb-ft.
The front cover is reinstalled temporarily, and the lifter valleys are plugged with shop towels, as the head-gasket mounting surfaces need to be cleaned with a craper and a 3M bristle disc; this will get the gasket off without hurting the aluminum. The head bolt holes are blown out with compressed air to get rid of any residual coolant, and they're threaded with a bolt to remove any sealant. These steps are critical, as coolant in a hole where you're trying to torque a bolt down can actually crack the block.
The new COMP lifters are lubed up, installed into their trays, and placed into the block. These high-energy hydraulic roller lifters are a performance replacement for the stockers. A 10mm bolt retains each tray, tightened snugly.
Time to replace the timing chain. The crank is rotated until the keyway is about at the 1 o' clock position-this allows the dot on the crank sprocket tooth to be straight up (top dead center No. 1).
Nick Stevko aligns the cam sprocket dot straight down to meet up with the crank sprocket dot, and then installs the three timing set bolts. The bolts are cinched up in a "star" pattern similar to tightening a wheel down. Nick wiggles the sprocket until the cam sprocket alignment pin slips into the sprocket hole. He then removes the bolts, uses red Loctite on each bolt, and reinstalls and torques them to 26 lb-ft.
The SLP oil pump will get the red spring for 5 extra pounds of bypass oil pressure. Nick installs it and tightens the cover down to 106 lb/in. It's easier to install the oil pump with the engine in the car if you take off the cover and pull out the gears, because it gives you more room move the pump to align the pickup- tube O-ring. Corvettes have room, but F-bodies are very tight in this area. The O- ring under Nick's left finger is lubed with engine oil before installation, and then he places the oil pump body over the crank sprocket, angling the pickup tube toward the front of the car.
He points out where the O-ring is seated. Though we used a replacement single iming chain, and therefore there is less of a chance for a problem, people who run double-rollers need to be very careful that the O-ring doesn't get pinched in the rear as the pickup tube is tightened down.
He uses a magnet to get this bolt back in. Although GM recommends dropping the oil pan, TTP saves a ton of time and hassle by using this method. He finishes tightening it by using a bent 10mm end wrench. The inner and outer gears are installed after he lubes them with oil.
The pump cover is placed and its seven bolts are tightened down, also to 106 lb/in. Nick Loctites the four oil pump-to-block bolts and spins them in by hand. They are tightened to 18 lb-ft.
With a new timing cover gasket placed, a dab of silicone goes on the bottom corners where the oil pan meets the block. The eight front bolts are lightly snugged, then the bottom two through the oil pan go in and are torqued to 18 lb- ft. Next, the front eight are torqued. Don't tighten the front bolts first, as doing so could crack the oil pan.
The graphite head gaskets are placed.
The Patriot heads are wiped down one last time, and Jason drops them onto the block.
The heads are now tightened; the long bolts are first torqued to 22 lb-ft, then 90 degrees, and on the final pass all the long bolts get 90 degrees; the shorter bolts on the upper corners only get 50 degrees. All the small bolts that go on the intake side (the upper part of head) get red Loctite and are torqued to 22 lb-ft.
The crank pulley is pressed back on, and a first tightening pass is made with the old bolt to 240 lb-ft. Once the pulley is fully seated,the Z is put into gear, the parking brake is set, and the new GM bolt is Loctited. As he did with the other torque-to-yield bolts, Jason marks the bolt head with a straight line and torques to 37, then turns 140 degrees.
Time to reassemble: The power-steering bracket, radiator, cooling fans, upper radiator support, and water pump go back on. The water pump bolts are torqued to 18 lb-ft. Then the coolant crossover tube, two radiator and two heater core hoses, A/C belt, and serpentine belt are reinstalled.
Both driver- and passenger-side Hooker headers are slipped into the engine bay from below. Note that some plasma cutter work had to be performed on the McLeod bellhousing, as the ear would have prevented the driver-side header from fitting. (This is not a poor header fit; we had to bash the stock cats to make them fit, too.)
Though they came with header gaskets, TTP only recommends genuine GM gaskets. A set is placed. "If you have someone to hold the bottom of the collector while you get the gasket placed and a center bolt started, it's a lot easier," Jason explains. This is a frustrating job for one person, but as Jason and Matt show, it can be done. Each header has six 13mm bolts (included in the kit with lock washers). TTP replaces these .75-inchers with Loctited 1-inch bolts, as the extra length helps with the install and no washer is needed. The headers are tightened to 18 lb-ft, working from the center bolts out.
After the AIR tubes are both blocked off, COMP's 7.400-inch .080-wall pushrods are dropped in. As they carry oil to the top of the valvetrain, the TTP staff checks each for any obstruction before installing.
The stock rockers are sprayed with brake cleaner and blown off with compressed air to be sure the bolt threads are dry, and then they get red Loctite. They are dropped on and then torqued to 22 lb-ft.
A new set of Zex's Power Tune spark plugs will be used. They are gapped to .050, antiseized, and installed by Jake.
The new GM spark plug wires are installed onto the plug. "You need to hear one click on the plug, two clicks into the coil," Nick explains.
TTP starts the fuel system upgrade by removing the plastic fuel filler housing and dropping the tank and exhaust heat shields. (Note that on early LS1s, the fuel tank and filler tube were metal, necessitating that, at a minimum, the Panhard and wheels be removed to get it out.) The stiffhard is disconnected on the driver side and pulled down, and the lower shock mounts are disconnected. The harness connections are unplugged and the fuel line is drained. Two tank-strap bolts are removed, and the tank is dropped.
Nick uses a brass punch (use brass or go boom) and hammer to unlock the retaining ring on top of the tank. Two electrical connectors and three fuel lines are disconnected, and the pump is removed.
He disassembles the bucket from the top assembly by using a screwdriver and pressing on two tabs on either side of the bucket. He uses a razor blade on the feed (left) and recycle (right) hoses to sever them...
...and disconnects the level sensor (upper right) and pump power (upper left). The pump filter is removed, and the pump is removed from the pump sleeve.
Time to switch over the two purple sender wires. Racetronix includes a paperclip to assist in removing the two terminals from the old connector. These slip into the A and D terminals on the new connector.
The new pump goes into the pump sleeve, then it goes into the bucket. Nick has cut a larger chunk out of the bottom of this sleeve so the filter fits correctly.
The new filter is snapped on, the pressure hose is placed onto the barb, and the worm clamp is snugged down. Be careful here, as this barbed fitting is plastic and it doesn't have to be ultra-tight. The recycle hose is reconnected to the new pump fitting, and the pump power harness is clipped in and retained with the new safety clip. That's it!
The Racetronix assembly goes back into the tank,and the ring and three hoses are reconnected.
The Racetronix harness connects inline with the original wiring, as seen here. Time to reinstall the tank. It is angled up and slipped into place, and Nick keeps an eye on the fuel hoses to prevent damaging them. The straps are reinstalled. TTP also took the time to replace the fuel filter.
The wiring is simple: Besides the tank connectors, there is one relay that mounts n the back along with a ground wire. The engine-bay wiring runs along the stock fuel lines, up through the driver side to the passenger side, and mounts across from the battery.
Finally, an affordable intake manifold and throttle body were bolted up for this story, but they caused wildly fluctuating air/fuel ratios on the dyno that TTP surmised was from a SBC-style intake gasket problem. Through several days of troubleshooting, nothing was able to fix it, prompting TTP to reinstall the stock intake and TB. FAST's 60-pound injectors were lubed and installed into the fuel rail, and then the rail assembly was installed. The stock manifold/throttle body was dropped onto the LS1, and then the coils and brackets.The injector clips, PCV and evap connections, coolant hoses, throttle position and idle air control connections, bellows, mass airflow, and SLP airlid are installed and tightened down. The MAF and IAT sensors are connected,and the oil tube and dipstick go in.
Six quarts of 5W30 Torco SR-1 synthetic oil were added along with a filter change. Torco's synthetic base oil and additive package is said to boost power and torque by up to three percent while eliminating harmful deposits and providing excellent longevity.
The Hooker Y-pipe and exhaust system are installed.
Hooker's exhaust system emits a great-sounding rumble with a dash of rasp, and its "dual-pipe" tips look great.
With all the goodies bolted up, it was time to hit TTP's dyno for a custom tune by TTP proprietor Matt Sorian.
The staff had drilled the stock throttle body's IAC hole to 7/32 to assist in a smooth idle with the big cam, and Matt adjusted the tune in HP Tuners.
When it was all said and done, the LS1's power jumped from 329 to 410 horses and 349 to 389 lb-ft of torque at the wheels. That's a total gain of 81 horses and 40 lb-ft.The final air/fuel ratio was between 12.6 and 12.7 to 1 at WOT. This LS1 ees 28 degrees of timing from 5,600 rpm on up to the 6,800 redline.
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