Jeff Eikenberry

I autocross a C6 with an automatic and F55 suspension, and also do about 4-5 track days a year. The transmission can't take the stress of track days (overheats). In addition, the automatic's gearing isn't the greatest for autocrossing and the paddle shift is too slow to react. I also suspect the sway bars are lacking, as well. There are too many things to improve to make the car perform at the level I'd like, so I've decided to purchase another C6 with a manual transmission. I've heard the Grand Sport does well as an autocross car. If I go that direction, is there any competitive advantage (or disadvantage) if the car has F55 suspension? Also, I'm interested in which is the better autocross car, a GS or Z06?

Captain Buddha

Jeff - I'm just a newb, so take my limited advice as that. My Vette progression and what events I've done:

2011 base vert m6: no events, decided I wanted a coupe/better handling (had some issues with car so it was an easy decision).

2012 Grand Sport Centennial Edition m6: came with MSRC - wow, what a difference! I have ran ~5 autocrosses and 1 track day with it. Handling was great, tires were pretty decent but got slick towards the end of their life (Goodyear Gen 2 tires, got ~7,800 miles). Traded this on my Z06. This was/is a GREAT car...reason for trading is that I wanted a Z06.

2013 Grand Sport auto6 (wife's) without MSRC: rides/handles differently that my GS with MSRC. This one has Goodyeard Gen 1 tires, not near as sticky as my Gen 2 or Michelins. Overall, the car feels "looser" and not as tight/nimble as my Centennial GS did. I attribute that to MSRC and the stickier tires.

2013 Z06 m 6: it has MSRC and PTM: so far I've done a few track days and have yet to autocross but will be doing one in a few weeks. Tires are Michelin PS2. In my opinion they are a stickier tire, I like them! Based on my experience with track days I'm betting this car is gonna do great...now the driver? Well, that's another story LOL. The PTM, to me, is a great advantage, it has 5 settings so you can tailor how much rotation you want...it's pretty cool...and it definitely saved my tail on the track.

Jeff Eikenberry

Sounds like you have the opinion that the MSRC system is better for racing than the stock GS suspension. Good to know. Will be interested to see how the Z06 performs for you. Obviously, it will do great; the question is how would a GS on the same course, running MSRC do. I've been told, twice now, that gearing gives the GS an advantage. Good luck and I look forward to hearing what your thoughts are once you run an AX in the Z06. Yes, I've heard the latest PTM used on the newer Z06 is absolutely phenomenal.

Captain Buddha

Jeff - just based on non-track seat time in both of the GS vettes I'd give the nod to the MSRC-equipped GS. Full disclosure - I have right-seated in my wife's car on the track (her driving) but I have not done any autox/track time with hers. I'm just not that big a fan of the automatic/paddles. I've driven her car like a bandit however and it is fun/easy to drive. I like to be more engaged though.

kimmer

If you want to have some real fun get a c5 z06 for autoxing.

Captain Buddha

A buddy of mine just got one and he had a blast at his first event in it (his 2nd overall event, he co-drove my GS last year for an event and got HOOKED!). A lot of car for the $$$. I like the looks too!

avizandum

The Z06 is preferred by national level drivers. The gearing is perhaps better on the GS but the diff in the Z06 has better clutches and hooks up better.

I agree that the C5 Z06 is a great choice too. All three are capable and until you're competing at a very high level, the shortcomings of one vs. the other are far away...

P.S. F55 is cool technology (and potentially capable), but ultimately limits your dampening choices and the springs are too soft for serious driving.

Jeff Eikenberry

I have first hand experience on why an automatic is not the way to go. I've hit the upshift paddle and waited too long before it switched gears. I snap spun as a result on at least two occasions........ both in corners, when I had hit the shift button on a prior straight. I'm now a big believer in more control (as in manual shift) in gear selection.

Jeff Eikenberry

You're absolutely right. I've seen exactly what you are making a point on....... a C5 Z06 is incredible. If I were more sensible, I'd do just that and be just a competitive. Sensible, I guess my detractors would say, I am not. Again, you are absolutely right.

Jeff Eikenberry

You won't get any arguments from me.

Jeff Eikenberry

Spot on! I'm 69 and know that to wring out every bit of performance in any of the cars you mention would be an achievement, for sure. I also tend to agree that you can be limited with the choices re the F55. As for dive, my C6 (non-GS) does dive dramatically.

TedDBere

Well, you asked which C6 was best for Autox so I'll give you my opinion on that.

Grand Sport, no F55.

Here's why. Better gearing than the C6Z for autox. Same wide fender flares as the C6Z, so you can put some monster tires on it that you may not be able to fit inside the base C6. Also with the wider fenders it's easier to upgrade the GS to the SSP and SSM rules if you decide to compete in those classes in the future.

I have the F55 on my C5 AE Coupe and the lack of adjustment limits it's autox suspension. It doesn't have enough rebound damping in the rear to hold the rear down during aggressive braking so spinning at corner entry is a high probability event in that car. On my C5Z I can adjust the shocks to my driving style a little better.

Having said that you may want to wait until the new SCCA rule proposals are decided since a move to street tires in all stock classes will make all the stock corvettes uncompetitive in the class with the GT3s and Loti.

Good luck!

autoxer6

The C6 Z06 isn't being used by anyone at the very top of super stock. It is difficult to deal with the gearing / power. The Grand Sport is the preferred C6 now. Sam Strano never thought it was the car to have, bought one because he liked it and thought he could deal with the gearing and in the end, sold it and is now in a Grand Sport.

For a C6 autocross, the Grand Sport is the only choice in my opinion. Espically if you want something easy to drive. The C5Z does pretty well on every course. I'm cheap, so I'll keep driving my C5Z!

Chris Shay

Captain Buddha

Well, grilled goat shishkabobs...looks like I'm gonna have to sell my Z and get my GS back!!

I've gotta tell ya, I'm curious as to how my Z is gonna do at autocross, I run in the Super Stock class. I'm curious regarding those that have ran in Super Stock with a Z06 - whether they had MSRC/PTM or not (believe PTM came with 2012 and 2013 Z06 with MSRC). You can dial up/down the amount of control/traction in corners...it's simply amazing from the few track days I've done so far. As an example...you can floor it out of a corner - too early? No problem...it feathers it back without killing momentum/shutting it down...it's crazy cool. Being a newb to this I find it a great learning tool.

I'm just speaking for the local Solo Super Stock that I run but 1st, 2nd 3rd are the same folks, they are all on R-comp tires, they have been doing it for several years plus (and usually every weekend with other autocross organizations) and usually it's a C5Z in first, an early C6Z in 2nd (although they swap 1st/2nd quite frequently) and 3rd is a C6. Then 4th is me with OEM street tires on my previous GS (Gen 2 Goodyears). Sometimes it's 4th out of 4....sometimes 4th out of 7. So, we'll see how it goes.

Jeff Eikenberry

The general consensus appears to be a GS without F55. As for your experience with the F55 issues, I had the same problem with my C6 F55. I tried different bars and alignments, but the F55, along with some 5 year old tires I bought new last year (grr) just couldn't be overcome...... the car snapped if pushed too hard. I liked your YouTube run. Jeff

Jeff Eikenberry

The case for the GS is becoming very compelling. As for a C5Z, I know they're great; I've seen them do some pretty remarkable stuff, but I think I'll stay with the C6 generation. Thanks much, Jeff

Jeff Eikenberry

Honestly, if I were willing to spend the bucks to get a 2012 - 13 Z06 equipped with MSRC/PTM, I jump ship and do it. It's a little more than I want to go, though. What I want is a car that will allow me to get into a zone; a predictable and solid performer. I actually have a car like that in an '84 Z51, but it's showing age and lacks power, not to mention that it's an automatic. There's a GS in my future.

Captain Buddha

Jeff - I'm in NO WAY knocking my previous GS - but out at the road course/track...yeeeeehawwww! My Z06 is a better track weapon than my GS. That is why I bought it...that and it is the last of the 427/Z06...at least for a few years. That's not to say that a half-way decent driver in a GS, or a base, or a ____ (fill in the blank LOL) couldn't kick my tail though.

Ya gotta get whatcha like!

Jeff Eikenberry

I agree with what you say, on all counts. If I could, I'd probably get a 2012 - 13 Z06, but that's not going to happen. The GS is not a bad second choice, though. Best of luck and don't let the GS's spank you on the track ! ! ....... unless someone puts a supercharger in......

Jawnathin

As its been noted earlier, MSRC is too soft for the aggressive driving required in autocross, even in 'Sport' mode. MSRC cars uses a softer spring than the standard cars and you can't change the shocks without losing MSRC, which was the whole point to begin with.

IMO, if the National Level folks thought an MSRC car would be competitive, they'd buy one. There is a reason why people pass on F55/MSRC on the GS too. Drivers at that caliber don't need/want PTM anyway, it just gets in the way. They turn everything off.

MSRC/PTM is a great at some things for some people, but not the ideal package in this environment at the National level IMO.