[VR] Heads/Cam/Header Grand Sports makes 502rwhp and 455rwtq
#1
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We recently had the opportunity to upgrade another one of our employee’s vehicles. This time on our Sales Manager Robert’s daily driven 93k mile 2012 Corvette Grand Sport that he recently purchased in 100% stock form. This car sees the occasional track day and autocross events but mainly is used for daily driving and mountain runs, so the goal here was not only to improve power and torque but also install a combination that would maintain drivability and reliability for daily use. Robert decided on our Stage 4 performance package for his car with a goal of 500+rwhp on the LS3 while staying naturally aspirated. Robert’s build featured the following:
· Halltech MF108 Cold Air Induction System
· Vengeance Racing CNC Ported LS3 Cylinder Heads
· Vengeance Racing Cam Kit Plus with KAOTIK camshaft
· LS7 Lifters
· ATI 10% Underdrive Balancer
· Kooks Header 1 7/8” Longtube Headers into a Z06 3” X-Pipe and OEM Z06 Mufflers
· MGW Short Throw Shifter
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For the camshaft we chose our KAOTIK profile which is a 235/243 .621/.624 113+2. The KAOTIK camshaft has been proven to provide big horsepower and torque gains while maintaining excellent drivability around town, making it the common choice for our enthusiast customers. With the camshaft in place, we bolted on an ATI 10% underdrive balancer knowing that Robert was going to spend quite a bit of time on track, and for a slight bump in power being that the stock balancer was removed for the install of the cam kit. Due to the high mileage on his vehicle we decided to go ahead and replace the factory lS3 lifters with a fresh set of GM LS7 lifters, new gaskets, and a set of ARP head bolts as well. A C5R timing chain was also installed replacing the nearly 100k mile factory chain when the camshaft went it. Also, since we were pulling the heads off and replacing a lot of the wearable valve train components anyway, Robert decided to upgrade his OEM heads to a fresh set of our CNC Ported LS3 Heads. The factory LS3 intake manifold and Stock throttle body were retained for the build.
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Robert was looking to get a more aggressive sound out of his Grand Sport while still maintaining factory exhaust and NPP bi-mode functionality. For this we turned to our friends over at Kooks headers who provided us with a set of 1 7/8” longtube headers and a 3” X-Pipe to mate to a C6 Z06 axle-back system. Once the build was complete it was once again time to hand the keys over to our trusted tuner to see what kind of numbers Robert’s Grand Sport would make. On our Dynojet chassis dyno Robert’s Grand Sport made 502rwhp and 455rwtq on pump gas all through the stock clutch, intake manifold and Throttle body! This was not only a huge jump in horsepower but in torque also that will translate very well on the street and track. This build was an absolute blast and we look forward to seeing this car ripping around Road Atlanta soon.
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Check out more of our Feature Builds, Performance Packages and Products at our website https://vengeanceracing.net/index.html. We have a wide range of performance parts on our online store for your LS or LT build. Feel free to contact us with any questions at Sales@VengeanceRacing.net or by phone @ 678-513-7105. We look forward to hearing from you.
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#10
TECH Senior Member
#12
TECH Enthusiast
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Awesome results. A friend of mine has this cam in his Grand Sport, it sounds downright nasty!
It appears that it made peak horsepower right when you stopped the pull on the dyno, why not rev it out more?
It appears that it made peak horsepower right when you stopped the pull on the dyno, why not rev it out more?