Life is Great with a 6.0-liter V8
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  • More than meets the eye…

    Posted on July 29th, 2012 tcorzett No comments

    I headed-out this morning to get some video footage of the newly rebuilt G8.

    Now, more than ever, the G8 really does have a split personally. Someone has even refereed to my G8 as a Transformer, so I wanted to highlight the two-sided nature of the car. Hopefully I got my point across.

  • The Six Million Dollar G8

    Posted on July 26th, 2012 tcorzett No comments

    Some have refereed to my car as “The Million Dollar G8”. I’ve never been a fan of that title, but I think I’m going to go along with it now…

    In April my engine got the flu and went in for service/repair. As the engine was being dismantled I kept thinking to myself: “Gentlemen, we can rebuild it. We have the technology. We can make it better than it was before… Stronger… FASTER!”

    After nearly 4 months, and just under six million dollars, my G8 returns to the road!

    Previously I added a TVS1900 supercharger, but didn’t open the engine to change any if the internals. Since the top half of the engine was now open to fix the broken part(s), I took advantage of it and replaced parts to make the engine better fit my performance goals.

    Cam:
    The G8 came from the factory with Displacement on Demand (DOD) that deactivated four of the cylinders to save fuel. I never liked the way this made the car behave, so turned it off during the last round of mods. Since some suggest the DOD hardware is a weak-link with the L76 engine… and I’m not using it anyhow… I had it all removed.

    The G8 is primarily my daily driver, so I didn’t want to go crazy and install a “donkey dick” cam (yes, that is the industry term) that would kill the drivability of the car. I also didn’t want to be forced to change to a higher RPM stall converter, again affecting daily driving.

    Ultimately, I wanted a cam that would give me more power than the stock one… but more importantly, I wanted one that generates more torque at the higher RPMs. With the Magnacharger (roots-type blower) I’ve had more low-end torque than I can put to the ground, but the car tended to “fall on it’s face” over 3200rpms (where I was at peak torque). Shifting the power curve a little should have a dramatic effect on the overall performance of the G8.

    Lastly, I have always loved the “sleeper” nature of my car, so I didn’t want to install a cam that would be too obvious while at idle. Many people like the old-school muscle car sound of a really lopey cam, but I’d rather no one know anything is different (until I blow past them at WOT).

    With all of this in mind, the cam chosen was a 223/231 0.610/0.610 117LSA

    Heads:
    Since the heads needed to be removed to access the lifters (the suspected failed part), it made sense to send them out to West Coast Racing for some TLC.

    Fuel System:
    The G8 has a decent fuel system, and can pushed with a Boost-a-Pump, but with this round of mods I wanted to take care of the fuel once and for all.

    I gave Andy at Squash Performance (a fellow G8 owner) a call and purchased one of his in-tank dual-pump units. With dual 255LPH Walbro pumps this unit can provide more fuel than I could ever use (with this engine block).

    The pumps are connected to a Hobbs Switch, which uses the boost from the supercharger to turn-on the second fuel pump when extra fuel is needed. A new fuel pressure regulator and 80lbs injectors were also installed to make sure the engine has a consistent flow of fuel. Everything is installed neatly under the car with the rest of the not-so-stock parts.

    Exhaust:
    For the longest time I had the goal of keeping my car “CARB friendly”. I ran shorty headers with HF cats, but was really hampering my car’s performance (especially on the top-end). Due to some unfortunate circumstances with a friend’s G8, I obtained a set of Kooks 1-7/8″ Long Tube headers. I’ve held-off installing them for such a long time, but with all the internal engine mods now was the right time. A custom connection pipe (w/HF Cats) was made to bolt the LT’s to my Corsa exhaust.

    With the long tubes the G8 is definitely louder, but at normal amounts of throttle it’s not too bad. What I love is just how raw the car sounds when I jump on the throttle! The first time (windows down, radio off, next to sound walls) I even scared myself a little. It will be interesting to see if I keep under Laguna Seca’s 92dB sound limit…

    Supercharger Pulley:
    The stock pulley on the Magnacharger is 3.3″ and was producing ~6psi of boost with the shorty headers. With increased exhaust flow, in order to not loose boost with the LT’s, a 3.0″ pulley was installed… producing just under 9psi at WOT. In the future I could increase the boost (either with a 2.8″ pulley or a rear overdrive pulley), but that will likely require the addition of a water/methanol injection system.

    Results:
    All of this is seems good on paper, but the proof is in the pudding!

    I’ve never been too concerned with the numbers, but I was pleasantly surprised when I heard my car is putting 537hp and 505tq to the rear wheels (an increase of 21%)!

    Drivability of the car is still very good. I’m having to get use to being in the G8 again (I’ve been in an SUV for the past 4 months), but nothing seems unpleasant. The idle is a bit rougher than before and there is more noise, but nothing crazy. Cruising on the freeway or being stuck in stop-and-go traffic is all handled smoothly. The added power is great, and the car feels much stronger at the top-end than before. I’ve only put 75 miles on the G8, but so far I’m very happy with all of the modifications.

    Like always, I really have to thank the guys at Synergy Motorsports for putting together such a perfect package.

    I still have a few more mods to install, but this is enough for now. I need to get some seat time in to shake-out everything before my annual pilgrimage to The National G8 Meet!