Cadillac CTS-V.R: Racing and winning in the Pirelli World Challenge


Lead Photo CTS-Vs 02The Cadillac CTS-V series of vehicles are General Motors’ prestige performance cars that are challenging the best cars the world has to offer. Cadillac has thrown down the gauntlet in the marketplace and they’ve taken the offensive to the racetrack as well. Team Cadillac successfully competes in the Pirelli World Challenge with the CTS-V.R, a special racing version of the CTS-V Coupe. In 2014, Team Cadillac will be defending their manufacturer’s championships and the driver’s championships they won in 2012 and 2013.

Pirelli World Challenge Series

The Pirelli World Challenge (PWC) is a production-based road racing series that provides manufacturers a competitive arena in which to prove their products. PWC races are sprint races of 50 minutes duration. There are no scheduled pit stops, no driver changes and not a lot of racing strategy—if a driver is not starting at the front of the class, he or she has 50 minutes of flat-out driving to get there.

Cadillac CTS-V.R

The Cadillac CTS-V.R is a specially modified version of the CTS-V Coupe. Anything that does not contribute to the CTS-V.R accelerating faster, stopping quicker or handling better has been tossed out. It weighs in about 1,000 pounds lighter that the street-legal Coupe and is powered by a 6.2-liter V8 engine that is restricted by PWC rules to 505 horsepower. Brembo brakes provide enough stopping power to make your eyes bug out and Pirelli racing tires give it plenty of cornering grip.

CTS-V 02Team Cadillac Drivers

The CTS-V.R is undoubtedly a superb race car, but a team doesn’t win consecutive championships in the very competitive PWC without exceptional drivers, and Team Cadillac has two of the best—Johnny O’Connell and Andy Pilgrim. Both are experienced and talented, and both have won multiple drivers championships in the PWC for Cadillac in addition to being successful at Le Mans and Sebring. The competitive fire still burns intensely and once the green flag drops, no quarter is asked or given.

Here’s a video of Team Cadillac in action.

New Players for 2014

Team Cadillac’s quest for a manufacturer’s GT Class championship three-peat this year was thrown a potential stumbling block by a change in the PWC rules allowing FIA-homologated GT3 cars to compete in GT. The CTS-V.R will now have to go head-to-head against some of the best cars in the world—the Audi R8, McLaren 12C, Nissan GTR, Lamborghini Gallardo, Porsche GT3 R, Acura TLX-GT and the Ferrari 458 GT3 Italia.

After four races at three different venues this year, it looks like business as usual—Team Cadillac finds itself in first place in the manufacturer’s points, while Johnny and Andy are second and third in the driver’s standings.

The next race for Team Cadillac will be the V-Series Challenge at Belle Isle, in Detroit Mich. on the weekend of May 30-June 1. NBC Sports Network will broadcast the race on Sunday, June 15 at 2:30 p.m.

Tune in and root for Team Cadillac to extend their lead, and for Johnny and Andy to move up in the driver’s standings.



V-V-V Shopping Spree

Darin Partin of Crest Cadillac emailed me to let me know they got in some new V-Series models on the used car side.

  • 2009 CTS-V 15,000 miles Red/Ebony
  • 2009 CTS-V 22,000 miles Black/Ebony
  • 2011 CTS-V Gray/Ebony 3,700 miles w/Recaro seat package

Of course I’m not in the market since my 2008 STS-V is still new-to-me, but I am always glad to see more choice V-Series examples pop up on the local sales scene.

The 2009-current CTS-V has the Supercharged 6.2L LSA V8 for 556 hp, magnetic suspension, Brembo brakes, and is quite literally a supercar in a tuxedo, with running shoes on, if that doesn’t ruin the metaphor for you.  And perhaps a tasteful tattoo of the rock band the V plays in.

My Wife sees exponentially more colors than I do, but feels cars should be pretty Red, so I was shopping for a red 2009 CTS-V when I found my 2008 STS- in Houston.  The STS-V has some luxury features the CTS-V line does not, but oh that LSA Supercharged 6.2L engine what a nice powerplant; the resulting power in the CTS-V is game changing.

These are terrific, world-class sports luxury cars and I hope they go to nice new homes where people can appreciate them.

So, if you have been waiting on the side lines for the ‘right’ time to grab up a nice pre-owned CTS-V you might give Darin at Crest a call; he has 3.



Intercooler Cooling: Corvette ZR-1 LS9, Cadillac CTS-V LSA, & STS-V LC3

The Chevrolet Corvette ZR-1 has a supercharged 6.2L OHV V8 engine.  It uses a TVS2300 supercharger with an integrated fin-type intercooler.  I am interested in the other end of the equation for this discussion, the heat exchanger.  Let’s look at how the Corvette design differs from my 2008 STS-V, and the 2009 CTS-V.

From our previous discussion, here is the intercooler cooling system for the 2008 STS-V:

STS-V LC3 Intercooler Flow path & Parts

Coolant flows from the output of the intercooler at the top of the engine through 26 and 27 to the front mounted heat exchanger 29.  After a pass across the heat exchanger, it flows to the intercooler pump 18 and then up via 25 to the intercooler at the top of the engine again.  There is a T along the way between 14 & 17 that allows for an up-pipe leading to a small reservoir and used for filling of the system.

It is not clear to me for the STS-V front-mounted heat exchanger how many ‘passes’ it contains.  Fluid enters at the top right and leaves at the bottom left, and may snake a few times across the fins of the heat exchanger on the way.  The GM p/n is 25770419 for the STS-V heat exchanger.  The heat exchanger on the car is not clearly visible for investigation.

We find a similar system on the 2009 CTS-V LSA engine.  The LSA is a supercharged 6.2L OHV V8 similar to the ZR-1’s LS-9 engine, except that it uses a TVS1900 Supercharger and has different internals.  As we will see, it also uses a different intercooler cooling strategy:

CTS-V LSA Supercharged V8 Intercooler cooling system

Here we see coolant flows from the intercooler at the top of the engine through 2 and 9 into the right or bottom side in our view of 11, then into 23 to reach the front-mounted heat exchanger 19.  After one pass across the heat exchanger, the cooler coolant flows out through 25 to the coolant pump 18, and via 14 back through the other side of 11, and along 7 back to the intercooler at the top of the engine.  Like the STS-V system, a T in the line at 30 just in from 2 allows fluid flow from the small reservoir and filling of the system.

The GM p/n is 25876663 for the CTS-V Coupe heat exchanger.

Mods: when modifying the CTS-V heat exchanger, D3 and Lingenfelter replace the stock one with a larger example.  Wait4me adds a second heat exchanger in front of the stock heat exchanger.

Now let’s look at the Corvette ZR-1’s LS-9 V8 system solution:

ZR-1 Intercooler System flow

Here we see the intercooling coolant flow into the front mounted heat exchanger.  Note that the front mounted heat exchanger is a 2-path heat exchanger.

Hot coolant flows from the intercooler at the top of the engine to the top row of the front mounted heat exchanger, and across the heat exchanger and into a inline reservoir.  From the inline reservoir cooler coolant flows back into the front mounted heat exchanger, then to the intercooler pump.  From the pump the cool coolant heads to the intercooler at the top of the engine.

The front mounted heat exchanger is p/n 20759871.  Yes, these three applications use 3 different front mounted heat exchangers.  Although there may be inherent benefits to the Corvette approach, it is also possible that due to packaging limitations in the Corvette there was simply less room available to use the larger area heat exchangers in the Cadillacs.

The STS-V system holds 2.6 quarts (2.5L) of coolant; the CTS-V holds 3.2 quarts (3.0L) the Corvette system holds 5.2 quarts (4.9L) of coolant.  Additional coolant in the system acts as a time buffer for changes in temperature of the system.  So when the coolant is heating up like wide open throttle from idle, then it takes longer to heat up.  However, when the coolant is cooling down like when high speed is pushing cold fresh air across the heat exchanger, it would take longer to cool down.

The pump in the Corvette is apparently different also; that’s a $1K pump where the one in the STS-V is under half that.

Ideas for Discussion:

Could the Corvette’s 2-pass heat exchanger and reservoir be easily adapted for use in the STS-V? Should it be? Only adding the reservoir might be an option, to boost the STS-V coolant capacity to near the ZR-1’s.

Does the STS-V NEED more intercooler coolant capacity?  I appreciate that it helps for back to back dyno runs, but on an actual drive there is high speed wind over the intercooler heat exchanger to compensate for the higher temps, and being able to quickly cool the intercooler coolant might be an advantage on the street.

Adding a second heat exchanger for the STS-V in front of the current heat exchanger would add fluid capacity and something less than twice the cooling, and be relatively easy to plumb.  However, it would require more experimental design to capture temps going in and out of the current heat exchanger under a variety of conditions, then in and out of the doubled heat exchanger in a variety of conditions.  The net effort might be less than worthwhile for the net benefit.