Predator Review for my 2006 Z06 Corvette

[EFEZ06]

After waiting a few months I finally received the Predator about two months ago but haven't wanted to install the tune until the weather (and the streets) got a little warmer, today was the day. It's still not as warm as I'd like but I got tired of waiting and seeing the unit sitting in my trunk every time I opened it.

The installation was a breeze and it went well according to the simple step by step instructions that came with the Predator. I hooked the unit up and after the first couple of steps my stock factory tune was memorized into the Predator. Then with a couple of more steps the Diablo Tune was installed into my cars computer, it took maybe all of two minutes. It appeared to erase all the computers settings and then installed the preset tune that Diablo has designed for the stock Z06. When it was complete it requested that I start and stop the engine - then it asked me to unhook the Predator.

First thing I noticed and I'll have to call Diablo to verify this is part of the design, it keeps my exhaust butterflies open all the time even when I try to shut them with my remote control exhaust switch. Evidently it disconnects the exhaust fuse circuit completely (in the computer) and it doesn't matter whether the fuse is in or out, in my case the remote switch off or on. Because the Predator is re-adjusting the fuel mixture I'm sure they want the exhaust to be consistent at all times and opening and shutting the butterflies causes a big change in the back pressure which will effect the fuel mixture.

Second thing I noticed was when I started the car and let it idle, it seemed to idle a little smoother. Maybe I was imagining it but that was my first impression. According to Diablo, they adjusted the timing and fuel mixture in their tune up, that would be noticeable in the idle.

While first driving down the street and punching the throttle I again noticed that the engine felt a little smoother, but hitting redline seemed a little strained, that could have been because the car was still cold.

I drove around town at normal speeds for the next hour or so. As the car reached normal operating temperature it began to feel as if it had more pep, especially when I up-shifted to the next gear. According to Diablo, they did design adjustments into the computer as you drive and shift gears. Now I was eager to feel it at full throttle again, but I had to wait until I got outside the city limits.

As I neared the edge of town I came to a turn entering onto an open highway and flew past a slow poke in front of me, that's where I first felt a difference in the power the car had. The Z zipped past the loafing driver and my senses told me to stay reserved because law enforcement has been known to hang around this area, my senses were correct! A block further a smokey the bear approached fast on my rear end as I was coming to a lighted signal at the last intersection before miles of open road. The lawman stopped directly behind me and was staring at the car that just moments earlier rocketed past the slow poke, did this officer of the law time me or estimate that I broke the speed limit even if it was only for a few seconds???

My radar was on but it never gave any signal, so if he were to pull me over it would have to be an estimated speed charge. The light changed to green and I took off at a fairly quick rate of acceleration but not excessive, got up to the speed limit and held it there (65mph). He trailed me for about a mile and I pulled to the right lane to see if he would pass, he did and we both stared at each other as he went by. I think he was hoping I'd keep up with him since he was going 5 mph over but I was a good boy and kept it locked at 65!

I knew with him cruising upfront of me (looking into his rearview mirror) this wasn't going to be the time or place where I could test my new tune up, so I reserved myself until I got off the highway and found a nice open road (at least for a few blocks) with no side streets and no traffic around. I hit full throttle for only a couple of gears and noticed something right away, the engine got to 7000 rpm very fast, faster than I've noticed before. 1st gear hit 7k in a blink, then 2nd gear hit 7k in another blink and then when I hit 3rd I felt more torque than I ever had before in this area (high altitude central AZ). I did feel this kind of torque when I was at sea level last summer, but here in the tri-city area at approximately 5000ft elevation the car just can't get as much air. With the improved power at this altitude, I can only imagine what it will feel like at sea level. To confirm my first impression at full throttle, I again opened her up on another desolate street entering a new housing development where I store my car. Again, I noticed how fast the tachometer reached 7000 rpm, really fast! The car simply accelerates faster and that's the only thing I've been able to test thus far.

Am I pleased with the performance the Predator adds at this point? Yes! The only negative I have is not being able to remote control my exhaust butterflies, not that I ever close them but it was neat to let others hear my exhaust notes go from quiet to rumbling! The instructions state that individual settings in the tune can be changed if necessary, so I'll call Diablo and see what I have to do to modify the exhaust circuit back to stock, although I normally keep it open all the time.

As I put more miles on the car under diverse driving conditions (mountain roads and straight out full throttle), I'll update my opinion! This is probably by far the easiest and quickest upgrade to add power to a new Z06 without bolting anything onto the car. It is not as custom a tune as an independent tuner and a dyno, but it is a simple way to get past the quenched factory tune, add some power and feel a difference.

Cheers,
EFE Z06

[mikel]

Glad to hear you are enjoying your new found power!
For what its worth, the last bone stock C6 Z06 we tuned on our dyno made 20 extra rwhp with the provided canned tune, and our GM tuner only found 4 more through extensive tuning...those tunes are spot on!

Thanks