Photography by: Vengeance Racing
Despite the internet lore that questions the potential of the C7 Z06, Vengeance Racing ignored the hype and got to work on their wicked white example. With bolt-ons alone they took the new Z from stock power figures of 585hp and 611 lb-ft to 661hp and 664 lb-ft at the wheels with a modified C7 AFE CAI, a slightly smaller pulley and a tune–that’s with the stock exhaust! These bolt-on results were achieved with the stock lower pulley and a 2.38-inch upper pulley that produced 11psi of boost.
But they weren’t done yet. Rather than stopping there, they added some American Racing Headers with massive 2-inch primaries along with a VR Stage 1 cam, CNC ported heads, supporting mods and at only 8-psi., they made huge numbers. Nope, that’s no typo! The cam and ported heads relieved so much restriction that boost was kept in check. The result? Try an astounding 745hp and 724 lb-ft a the wheels with the STOCK lower pulley, STOCK throttle-body and with STOCK compression.
According to David at VR, there’s still plenty of room to grow with the current setup since the Stage 1 cam isn’t overly aggressive to preserve driveability and the heads could also be decked for a slight increase in compression. The addition of a more aggressive cam and a hair more compression would likely move the car to roughly 800whp with the small(ish), stock Eaton blower. If you ask us, that’s just crazy!
Here’s a peek at the LT4 heads!
Here are the details:
VR CNC LT4 Cylinder Heads
VR Custom Camshaft-Deletes DOD/Retains VVT- MILD
VR Dual Spring Kit
VR Hardened Pushrods
Katech C5R Timing Chain
B&B Fusion Catback Exhaust
Alky Control Methanol System- Not used due to current boost levels
Lashway Catch Can
LMR 160* Thermostat
Modifications prior to heads/cam upgrade:
VR modified AFE Cold Air
2.38 Upper Pulley
ARH 2″ Stainless Long tubes with 3″ X-pipe
Here’s what VR had to say,
“Our previous best numbers were achieved with 11psi using the stock lower pulley and our 2.38 upper pulley. After the heads/cam upgrade we are producing 8-psi. across the board. Now that we know what kind of power we can produce without over-spinning the blower we are having a larger lower pulley designed to see if there is any additional boost to be gained as some shops have reported.”
They also added, “Results on 8-psi… 745RWHP/724RWTQ!!!! These numbers are WITHOUT over-driving the blower significantly… 157RWHP/107RWTQ gain over stock baseline numbers with 3-psi. less across the board!”
Raised in a house of hotrods, classics and motorcycles, it only made sense that he would blend his love for writing and photography with his love for all things automotive. Armed with a degree in journalism and graphic design, he embarked on a journey into motorsports journalism and has worked for many magazines and Websites chronicling his love for the industry.
