huntfortravel

I don't fully understand gear ratios, so I have a 2-part question on which I need some qualified opinions. I am looking for a C6 LS3(possibly an LS7, but that's a different set of questions). Depending on what the gears are, is the top speed the same for the 6-sp manual as for the 6-sp automatic? I know in theory the top speed is supposed to be 190 mph, and I also know the base model is a little faster than the Z51 all things being equal. I plan on shipping this car to Germany to drive on the autobahn, so I'm wondering how fast the car can be driven(if it's unmodified) on a consistent basis. I have a euro-spec 1999 BMW 328i that can run at 150 mph all day long with no issues, so I'm wondering what sort of performance in general I can expect from an LS3. I like to mash the gas and go, so I'm excited about the possibility of getting closer to 200 mph. Or over.

FAUEE

There's more to it than just gearing.

​​​​​At lower speeds like 150 your BMW does, you might gear out for your top speed. But when you get closer to the 180, 190 and above speeds, gearing usually isn't the limiting factor, it's power and aero. To go 1mph faster at that point requires substantially more HP than it does at 150mph, especially depending on the aero.

Then you've got lift that will destabilize the car at speed. The air running under the car pushes the car up, reducing grip. At 180-190 top speed in a c6, if you have to make any sort of emergency correction you're pretty much toast. Say a deer jumps out and you have to move over, you're probably not gonna be able to hold it, and likely going to have a NASTY wreck. You combat that with more down force, but that extra down force reduces your top speed.

Basically, you have to decide how fast you want to go and how safely you want to do it.


The c6 with the LS3 or ls7 doesn't top out over 200mph stock. I think the zr1 did, though.

PAPAYOYO

Alot of Americans die on the autobahn every year...Speed is different .Just little FYI

Silvio61

LS7-198 mph
LS3-190 mph
LS2-186 mph

HOXXOH

I've had my nearly stock '08 to 150 easily. A GPS confirmed 174, and a few 180+ dash visual images. The car is capable, assuming the tires are also.

DrKrieger

My S/C'd LS7 easily achieves 175.......then I chicken out with the "lift factor" of the front end! Then, I think of getting caught doing those speeds and losing my car and my license, and then thinking of the possibility of something on the road, or a blow out. Life would tend to be over as I have no roll cage! I've been on the autobahn twice, once in a Lambo Gallardo, and once in a BMW M5. Scary as hell with the weaving in and out of traffic. Reached 180 in the Gallardo, 168 in the Beemer (I wasn't driving either time), and that was enough for me.

VetteVinnie

LS9-205 mph.

huntfortravel

With that being said, how smooth is a typical LS3 Vette at the higher speeds? My Bimmer at 150 is very smooth and straight. I haven't driven an LS3 yet, so I'm curious to know its handling capabilities. I intend to learn about it as well as I can by exporing its limits in a sensible way and in the right place.

allhans

Fast!

StayinStock

My c5 felt very floaty above 150, you could feel the front end lift a bit... my c6 seems much more stable though ive only had it up that fast once or twice and never much more than 15-20 seconds...

FAUEE

They're a different kind of fast. The BMW will take a while to get to high speeds but is designed to stay there. The Corvette is more like a track car, designed to get to high speeds quickly, stay at the briefly, then slow down for a turn, and accelerate out quickly again.

I wouldn't want to drive it at 180mph consistently personally. It's just not designed for that.

VetteVinnie

From personal experience with those speeds, adding the ZR1 Aero to my 2008 Z06 was the best thing for it because it felt a bit floaty. I was amazed how well that aero worked. It makes perfect sense to me why the ZR1 appeared so stable during its high-speed test run (hit 207 MPH on their test track). Of course, suspension plays a huge role. My Z06 had DRM Bilstein shocks with the updated bushings and the ZR1 has magnetic ride control. I had my Z06 up to 184 MPH (and it was still pulling hard) and my ZR1 up to 165 MPH (ran out of road).

If you use the ZR1 aero, please make sure you add the fascia reinforcement because the fascia can deform at high speeds.

Side note, my Grand Sport has magnetic ride and APR aero, so in theory it could get up to those higher speeds, but with the convertible, I have no idea how it would perform in comparison, so I haven't even attempted it (and I doubt I will).

huntfortravel

THAT is the kind of input that I need. I want to drive it fast from an acceleration standpoint and from a top speed standpoint. Not having owned a C6 before(I have a '95 LT1), I'm not aware of how stable they are at high speeds. Where did you get the ZR1 Aero package? And if I am going to drive at high speeds do I need to replace the shocks as the first order of business? And thank you for "steering" me in the right direction(couldn't resist a little drivetime humor).

3LZR21U

Keep in mind that in many places, you're going to be limited to 130 KPH. And there are a LOT of speed traps where the limit will go up and down almost without warning. Rarely have I ever stayed above 160 KPH for any length of time, and virtually never above 180 KPH. 150 MPH (let alone 180 MPH) is realistically not going to happen.

And they will hold you accountable for excessive speed if you get in an accident. There may be no speed limits posted. But if you're in an accident and you're doing 200 KPH and they are doing 130 KPH, you're going to be found at fault. I'll put money on it.

huntfortravel

How stable was the car overall at 180?

VetteVinnie

There is front lift in stock form (on Z06 without CFZ and Grand Sport), so I would put aero as a higher priority, personally. They do make kits for the base model cars also, but I do not have personal experience with those.

My Z06 had RPI Designs (with an APR spoiler). My Grand Sport has APR splitter and side skirts with an unknown manufacturer on the spoiler. A shop sold me some "carbon fiber" aero when I first bought the car last year, and they installed it before I really had a chance to look it over. It turned out to be cheap fiberglass garbage with a thin layer of carbon fiber. It was strictly for looks, obviously. This happened on day two:



The APR splitter is considerably stronger and true carbon fiber throughout (hence why it's not cheap). This is their Type I. Their Type II is a ZR1 replica with the same undertray (something the ZR1 did not have).

huntfortravel

Where I live near Ramstein there are some nice unrestricted stretches of the Autobahn no matter which direction you go. During the spring and summer months I routinely get on the road to get my "speed fix" at 150 mph. I took my BMW to Hochenheimring this past May, and had a blast. I hit 150 mph on the way to the track, did 14 laps(2 burst of 7 laps each), then hit 140 or so on the way home. Nurburgring is hopefully next once the weather breaks. You are right about being restricted to 130kph in most places on the autobahn, but once you get out between towns in the country areas, it often opens up to an unrestricted zone, sometimes 3 lanes wide.

VetteVinnie

Incidentally, I know for a fact that suspension plays a role because on one high-speed run with my ZR1 I forgot to put it in Sport mode, and the car was moving around a bit more than I expected. Once I put it in Sport, it was rock solid again. I never tried anything in my 2006 Z51 base coupe (never modified it). I was in a Z06 before I could modify that base coupe.

dr_gallup

Years ago I had a little BMW on the autobahn that I held flat out for about 20 minutes at 210 KPH (130 MPH). All of a sudden I heard this outrageous sound, thought the motor was about to blow then a Lambo blew past me at least 30 MPH faster. So don't forget to check your mirrors frequently.

Aardwolf

If you get a model that has the under area open to the radiator closing that off will help with less high speed lift. Some models, I think all base models, are both a front and bottom breather. I've done the mod and there is less float feeling at high speed. Also I didn't notice engine heat being bad but I haven't let it at high speed for many mins.