You probably already figured out I tend to be long-winded, so get ready. I just went through all this and it's now been done long enough that the new has worn off. Be prepared for some ruminations.
You might want to start by
reading this. It's another ruminations post I made right after I had the headers and other mods done.
I dunno. Changing out a catback for more sound, sure, that's a no-brainer. If you choose the right one it has no real downsides other than the hole in your wallet. (A Corsa is the right one for you, it's the only one approved by GM, for a reason. I'd get the Pace Car system, the Touring is almost the same as stock. Choose tips to your choice)
But beyond that? Think hard. I mean think
long and
hard about what you want from your car. Right now you have a BRAND NEW Corvette. Wow. There ain't many things in life cooler than that. I'm here to tell ya, once you start modifying it, it won't be the same car. It won't be that new Corvette again, not ever. That's what happened to mine, which I bought essentially "new". So think hard.
I know, I know, everyone in the forums just gushes about how great all their mods are and how they love 'em and how they can't wait to get more. Uh-huh. Thing is, they never talk about the downsides. They never talk about what got worse on their cars with the mods.
Here's the deal: when you modify a car,
in any way at all, YOU are now the automotive engineer. An amateur automotive engineer. In your case, doing your apprenticeship on a brand-new $60k car. While you may well change some of the design decisions to tweak the car to a spec more of your choosing, it is virtually inevitable that in some areas it will get worse.
I'll give ya some examples from my own car. Some of these will seem off-topic, but bear with me.
Lloyd mats: no downsides, great mod. Get the clear plastic overmats to cover the front mats. Yes, it seems silly to buy mats for mats but they work.
Plastic sill protectors.
Like these. They do a good job of protecting the sill, but they scratch the paint on the sill at the front edge of the protector. They also get water under them when you wash the car, so you have to take them out first, and then wash and dry them separate, or you get ugly water marks. IOW, they're worth having, but they ain't perfect. A typical mod.
"Billiard ball" shift knob. No downsides, love it.
Z06 Titanium catbacks. No downsides (note: not so uncommon with factory parts). Look better, sound better, lighter, exotic, maybe another pony or two.
Elite Engineering tunnel plate. This was the first mod that had an unpleasant side effect. I put this in when the car was near-new, as I thought it would keep it from getting rattles quite so fast. So far, so good, almost 24k miles and no rattles yet...except for one. I had the plate installed the day before we left for our 10k-mile swing around the Western US last June (note to self: never get mods done just before a long trip). The mechanic got careless and managed to strip one of the attaching bolts out, so had to drill it out and tap it bigger. I was not pleased. But here's the weird one: I never had any shifter rattles before installing the plate, but the shifter has rattled badly ever since. It's enough to make you crazy sometimes. Yeah, yeah, C5s "do that"...but mine never did until that plate was installed. That was the first inkling that modding this car was going to have downsides. Is there some reason why the plate should make the shifter rattle? Beats the heck out of me. They aren't connected and you don't touch the shift mechanism when installing the plate. So then what? Who knows? I theorize that making the bottom of the tunnel stiffer has caused the vibrations of the drivetrain to be less dampened, and this was just enough to excite the shifter mechanism. All I know for sure is that it rattles, and it seemed a lot less like a world-class car once that started. From installing a tunnel plate. Who'd a thunk it?
Elite Engineering radiator screen. Keeps crap out of the radiator. What could be the downside with that, you ask? Well, it no longer allows the front spoiler to rotate back on its hinges when it hits something. So the spoiler is wearing away faster. No biggie, it's like a $20 part, but still...you change it, you're now the engineer, there are Consequences.
After that stuff there was a lull while we went on our trip, and after we got back I was sort of in a daze so didn't drive the car much for a few months other than commuting.
In the fall the driving started again in earnest, and the mod bug bit again. This time we were going to head down the engine mods path, as you are contemplating.
I ordered a Honker, and I ordered the American Racing headers. Both took forever (it seemed) to arrive and I got impatient. I had gotten really tired of the quietness of the Z06 exhaust after hanging around with the folks in TBV. I wanted louder! I wanted more exciting! There was a vendor at the Ultimate Vette Party that had B&B Bullets at a reasonable price. I had read about them and they sounded like what I wanted, so I went ahead and bought a set. Between the pipes and install, call it $700.
Wow! Are these LOUD! At least that was my first impression. I'm more used to them now, but they are freakin' loud, there's no doubt. No more smooth, sophisticated car. No more grown-up car, now it sounds like a "kid's car". No more cruising at a walking pace through state parks, listening to the birds (something the wife and I love to do). No more banging gears without drawing attention. The vibrations can be felt through the seat, steering wheel, and door panels at certain speeds. I suspect they are exciting interior rattles. It's not rattling yet, but the panels are moving and I think it's just a matter of time. It also didn't run quite the same after the install. I think the reduced backpressure was just enough to throw the computer off some. Running through the gears, the Bullets sounded GREAT! Just what I wanted. The rest of the time? Well, there are pluses and minuses. For example: I live in an apartment, and leave for work quite early. I used to let the car warm up pretty well in the morning. Now I feel self-conscious making that much racket at 6 AM, so I fire it up, wait for pressure, and drive very slowly away. Because of that, it's not up to temperature by the time I hit the freeway ramp, so I don't get to do my usual wail up the ramp. Hmmm, those unexpected consequences again.
The came "the big one" (so far), as outlined in that other post. Headers, cold air intake, thermostat, dyno tune. This has various pluses and minuses which I stated there. I will say here that, now that I'm more used to it, I do like the sound. It's just different from what I expected. It is LOUD, and that has downsides as mentioned above, only now it's quite a bit louder. I was surprised the headers made that much difference, but they sure did. Greg predicts that I'll eventually be back to have the Bullets taken off. We'll see.
Biggest downside? My gas mileage has gone in the toilet. I've dropped a solid 4-5 mpg in DIC mileage. A small part of this is the tune, I think, but a much larger part is the change to my driving habits. I used to drive fairly conservatively, and just bang it through the gears (regularly) but then ooze around at 1500. Great mileage that way. Not anymore. Two things are going on with that: it feels so much like a "race car" now I just HAVE to rev it up all the time, just to listen to it. Plus pass
everyone. I'm driving a lot faster. Not sure this is a good thing. It's fun, though. I know, I should have more self-control. I wasn't born with much and little more has come my way. Second is that the Bullets + headers have a bad drone between 1500-2000 so I have to keep it above 2000 all the time. On the freeway this is unfortunate because my usual cruising speed is 80, and that works out to 2600 rpm in 5th. Can't hit 6th until 90. Ouch.
Another downside is that it has some trouble idling. The tune needs work. Yes, I could take it back and have it jiggled, but it's a long drive and most of the troubles are when it's cold. I'm just going to get my own tuning software. There's another $750 or so.
The car definitely makes more power, and more torque. Not just on the dyno, but on the street and at the strip. It's alot of fun to drive. But now it has a little more power than the stock clutch can hold. So a clutch upgrade is in the works, and I have to be a little careful until that goes in. It'll run about $2k (premium parts again), plus whatever else I get done at the same time. More Consequences.
Oh, I guess the BIGGEST downside to the last package of mods is that it ended up being $4325 for 27 rwhp. Wow. Ouch. $160/rwhp, PLUS all the downsides mentioned herein. And yet look at it, where was there to cut a lot of money out? Sure, I could have bought lesser quality parts (or maybe I got took, you judge), but I certainly didn't get "ripped off" on anything. I bought popular parts that are on the "most recommended" list and paid fair prices for the parts and install. What's different about me is that I kept track of the costs and published it for all to see. Not too many do that.
Overall, today it's a long way from the smooth, sophisticated, fast car that got great mileage that I bought. A long way. Was the journey worth it, and would I recommend it to others? Hmmmmmmmmm......
In my case I think it's something I "had to do", and needed to get out of my system. I am having a lot of fun with the modded car, and I'm going to go farther with it, but yes, I VERY MUCH regret what I am losing in the process. Modding has definite downsides to more than just your wallet. So the point of all this was not to say "don't mod, it sucks!" but to just show you some of the "dark side" no one talks about, and suggest you consider very carefully. You have a new Corvette, a "virgin" if you'll excuse the analogy, and that's something you can never get back again.