I checked out this '03 Z06 yesterday (Tuesday). I figured I'd post about it since there was a long thread on the FB C5 Z06 Owners Group asking for opinions on buying it. It's posted on FB Marketplace at a dealership in Ozark, MO, with an asking price of $25,999. Most notably, it's cammed, has headers, and C6 Z06 brakes. It also has an aftermarket fuel rail, a fuel pressure gauge connected to the fuel rail, and a-pillar pod gauges for fuel pressure and AFR. I think it has a square wheel setup as well (didn't measure the wheels) with Falken RT-615Ks, 275 front and 305 rear, all 18s. The 275s look kind of stretched, the 305s look "right", which is why I'm assuming the front wheels are the same width as the rear.

When I showed up, it was raining, so I didn't get to see the Z06's paint unfettered, but I didn't notice any rock chips up front or any paint fading. I did notice that the rear of both headlight covers is hitting the hood as there was a rubbed-away spot on both covers. The black interior looks to be in really good shape as well.

Disclaimer: I have never driven any C5 before, much less a cammed Z06. My current Vette is a C7 Z06 7MT which is pullied and tuned, so it's a torque monster. I fired it up and the first thing I noticed was that the oil pressure gauge read zero. There were no idiot lights, though, and I'd checked the oil before hopping in and there was some, so I assumed bad gauge or sender. The second thing I noticed was the "service steering column lock" message. The third thing I noticed was, oh man, this whole thing shakes a LOT at idle. Is it common for cammed Vettes to shake THIS much?

I pulled out onto the main road and drove the Vette gently as it was pouring rain. It had a hanging idle when I'd push in the clutch--around 1500-1800 for several seconds before dropping back down to around 700. It wasn't nearly as loud as I'd expected for a headers, no-cat (I assume) car--my C7 which is headers and no-cat through stock mufflers is wrath-of-God loud when the valves are open, even at idle. The ride was C7-Magneride-in-track-mode rough. Not terrible--20-something me would appreciate it but 50-something me finds a little bit too rough.

The clutch was nice and light, with no slippage or chatter, and smooth engagement. The shifter, which has a C6 **** on it, felt really direct and connected. Not quite so direct as the T56 in my '03 Mustang Cobra (a the-shifter-bolts-directly-to-the-top-of-the-tranny setup), but more direct than my C7.

After the oil temp was up into the 160s, I started being a bit more aggressive with the throttle, and was.. underwhelmed. I eventually went WOT in second gear from about 20mph, and not much happened. So then I turned off the traction control (in the pouring rain, on 200TW track-oriented tires, mind you) and went WOT at 20mph in second again. The car just stuck, until about 4500rpm at which point the back end started to sashay a little bit so I backed off. I was blown away--I figured this thing was going to try to pirouette me into the weeds, but no. I get that camming a car moves the powerband up in the RPM range, but it felt like a small-displacement turbo car that was off boost. Maybe that's how it's supposed to feel, but...

I can't help but wonder if this car wasn't supercharged, and then a PO removed the blower before selling it but didn't bother to retune it. Maybe the tune has the timing set really soft in the midrange to avoid detonation under heavy load, low RPM? I've never seen a normally-aspirated car with fuel and AFR gauges, but those things (at least AFR) are common in force-inducted cars. The guy who traded it into the dealership was not the owner who did the mods (Carfax showed three owners), and he didn't have any paperwork to go with it, so right now it's a mystery.

Anyway, the two dealership guys were really pleasant to work with, but I wasn't getting the feels that I thought I was going to, so I walked. I'd showed up with funds to buy, figuring this would be a somewhat-down-on-power-but-not-a-pooch alternative to my C7 that would be give me the raw, enjoyable feels that I get from my Cobra, but no. The Vette appears to be in overall nice condition, so if this things seem like minor hiccups to you, I recommend checking it out.

 

I would think there has to be a tune issue that has the timing retarded big time for it to struggle to break loose and not want to show door handles to passing cars.Man I miss my yellow Z,appears to be a fairly good deal from your description and the asking price.

 

It definitely sounds like its got some issues. Based on it's uncertain history, I'd probably stay away from it as well. The extreme shake at idle is not something I would want either. All C5s are quiet from the factory, and all C5s have the potential to be wake the dead loud. However, headers alone with the stock exhaust won't be particularly loud. I have a supercharged vert (not for sale) that would probably be closer to the "feels" you're looking for. However, it definitely sounds like what you drove underperformed it's potential if everything was done properly. Thanks for the review.

 

The cam sounds to big for the car, are you saying it pulls hard above 4500 RPM, no low end grunt? No oil pressure, don’t assume it’s a bad sensor, and they let you test drive it with zero oil pressure. What the hell.