Experience the 2005 LS2 GTO
Article by Jonathan Schwenn
Photography by Bob Fischer
I was granted the opportunity to visit the herd of 2005 goats down in Arizona recently. When I pulled into the Bondurant facility, I observed that they were lined up and ready to go. The first thing I noticed out of all the cars was the cyclone gray and midnight blue colors. You will notice that most of the photos taken were of those two cars.

The 2005 GTO is actually much more different from the previous model year than was thought before. I struck “nerd gold” by having time to talk with the US and Australian engineering team leaders. The most obvious change is the new LS2 motor that for the most part everyone knows about, same as the 2005 Corvette. Larger bore LS1 basted motor with new cam sensor and knock sensor placement. Larger intake and throttle body. Static Compression Ratio is raised and the heads are revised LS6 '243' heads.
The 'E40' PCM in the 05 is brand new along with the drive-by-wire throttle body system. The traction control is not as much of a “push back” system anymore. Traction Control is now managed with spark, brakes, and cylinder cutout. I experienced it and it seems to cut more timing then last year. The new PCM is located where the coolant overflow tank resided on the 04. The area between the frame rail and the driver-side exhaust manifold now has much more clearance. The coolant overflow tank is relocated to somewhere below/in front of the air induction box.



The ABS system is a new Bosch 8.0 unit with electric brake distribution. The front setup comes from the Corvette style 40.5 mm twin piston calipers and 320 x 32 rotors. The rear calipers were also painted to match but are the same as the 2004 GTO, however the rear rotors receive a slight upgrade from a non-vented rotor to a 286 x 18 vented rotor. The Master Cylinder is an improved 25.4 mm unit along with an improved 8"x9" booster with a dual reaction ratio ("Brake Assist") designed to give a better apply rate above 0.5 to 0.6 g deceleration.
The exhaust is very different this year with new manifolds that have less restriction along with a crossover resonator and dual exiting exhaust. The mufflers were said to be less restrictive as well by a small percentage.

What was surprising was the fact that the drive train was also upgraded. This does make sense, with the added power output. The pinion gear is stronger, there was a material change and it is shot peened. The CV Joints are from the HSV parts bin from AWD VZ range.
The interior remains mostly unchanged. The font in the gauge cluster is more italicized then before, and there was an addition of a dead pedal/foot rest. The dead pedal is covered by carpet. It was useful when trying to hold myself in the seat while I was whipping around the track. The pedal locations have been adjusted slightly. I can comfortably fit my foot between the clutch pedal and the kick panel whereas my 2004 I cannot.
The exterior changes include a new rear fascia, new exhaust system, and as well as a new scooped hood. The rear fascia was changed in order to accommodate the new exhaust. The hood scoops have a rubber baffling system to keep water out and let air in. For those who have garage queen GTO’s that do not see the rain (like mine), a popular free mod will be to remove the baffling. All the badges were updated to the 6.0L designation and the rear trunk lid now sports a “Pontiac” script on the driver side.
Now the guys at Pontiac wanted to do a little more than just point out the differences in the car…. they wanted to show me what the car actually can do. I took a Quicksilver 05 GTO out on Bondurant’s course to put it to the test. The car had amazing pull (for stock) and even though it was just a small road course, I was in excess of 95mph on the strait away. The traction control only got in my way a few times but for the most part did not affect the smoothness of the drive. Excessive wheel spin seemed to cut the power down quite a bit, but the little tire chirping was not a battle with the accelerator pedal.
This is the part were it just gets a little bit crazy. Rhys Millen was eating lunch with us and seemed like an awesome, down to earth guy. Now the first time I talked to him I was sitting next to him in HIS GTO. Right before he was about to show me a little about what its like to travel sideways he chuckled while looking over and said “Hi, I’m Rhys… nice to meet you...” I said “Hi, I’m Jon” but I was thinking more along the lines of “I’m dead”. Surprisingly his driving is VERY smooth and was not scary at all. There is not a great amount of speed with drifting and I felt safe with Rhys at the wheel (I was also in a 4 point harness with a helmet).
Now you must think this is the end, it could not have gotten any better…. well you are wrong. Bob Bondurant is a great guy, I have met him on more than one occasion. Now I do think he is a little crazy with how he drives, but hey …. that is his job, he knows what he is doing. Therefore, he grabbed the key to one of the Yellow Jacket 2005’s and headed out on the track. Doing amazing drifts while Rhys was matching his line. What was even more amazing is that this was a STOCK GTO.
 
Pontiac/Bondurant wanted to extend the experience further and let me drive one of the 2004 GTO’s they use to teach their drifting course. Now this is where the impressive feats of blazing tires stops and me spinning in circles takes over. I have the theory down but have not yet mastered the coordination required to pull it off. It is a lot more about balance and momentum then power. Oh, and it takes balls to take a turn going that quick. Pretty much, you need to turn quick, transfer the weight to the front by gently applying the brake, and carrying the car sideways then with the throttle.