We here at Weapon-X Motorsports pride ourselves in being at the forefront of the aftermarket LS/LT community. Not every shop can say they were the first in the country to license and tune a new model year 2017 CTS-V, but then again, we're not your average shop.  We stand for constant innovation, and would like to showcase our X800 package available for all LT4 equipped CTS-Vs.

 

Bob G brought us a brand new V3 with less than 150 miles on the clock.  After some time behind the wheel, we strapped this sleeping beast down on our MD AWD-1100 dyno to get some baseline numbers.  Most LT4 cars put down horsepower in the 550-570rwhp range, and this CTS-V fell right in line, making 559rwhp and 577lbft of torque.  Now the only direction to go is up!  On to the modifications!

 

 

 

We have seen first-hand what modifications work and don't work on a stock LT4 bottom end, and we used this knowledge to put together our X800 package.  Drivability and street manners remain fully intact, and other than the more throaty exhaust note, you would have no clue that an additional +140rwhp is ready to be unleashed to the pavement. At the end of the day, no matter how complex, an engine is an air pump.  We know how to improve efficiency and let these LT4s breathe.

 

The X800 package mainly consists of a set of Weapon-X ported LT4 cylinder heads, WXM ported blower, custom WXM camshaft, Stainless Works full exhaust (long-tubes, off-road x-pipe, and mufflers), WXM intake, 103mm throttle body, 10” lower ring, and our WXM Heat Exchanger (HX) package.  In addition, the owner also opted to install a carbon fiber driveshaft as well as our WXM Stealth Cooler system.  A full list of installed modifications can be seen below.

 

  

 

With all of the aforementioned modifications installed and everything in working order, tuning the setup for power could begin.  It should be noted here that the added cooling capacity greatly aids in tuning time, as less time is needed for cooling between dyno runs.  Before the HX and Stealth Cooler were in place, the LT4 blower would be heatsoaked after one dyno pull, and would need almost over an hour to cool down sufficiently so that air temps could all be in the same ballpark temperature to accurately measure gains from pull to pull.

 

After all was said and done, the final numbers for the V3 were at an even 700rwhp and 697lbft of torque.  This is a gain of 141rwhp and 120lbft of torque.  The torque increase was seen everywhere in the powerband, all the way down from 2200rpm to 6400rpm redline.  This V3 definitely moves now with the additional torque and horsepower.  We can't wait to see how the V3 performs at the track.  Using the capabilities of our MD AWD-1100 dyno, we were able to measure a quarter-mile sprint in the low 10's at over 130mph.

 

In closing, the X800 package is a refined choice of modifications meant to let the LT4 shine without resorting to a stroker setup.  A new set of rear tires should be on the future modification list, as this thing will absolutely roast the tires either from a stoplight or from a highway cruising speed.  More power is able to be made in the future with the addition of methanol injection or e85, but for the average V3 owner, this power level is more than enough;  That is, until one needs to scratch the modification itch again.  When that time comes, we here at Weapon-X Motorsports will be here waiting to take this build to the next level.