truth.b

Yes, my tires/brake/suspension comment was referring to the 2010 GS and C6 Z06.

dhowdy

I can't speak to the integrity of his source data, so definitely possible. Also the thrust calculation wouldn't take into account the available traction from an extra 1.5" of tire in the rear, which could definitely help.

STANG KILLA SS

im in this same boat
also factor in availability of parts if you plan on keeping the car for quite a few years.

this is one of the main factors im leaning towards the C6Z

C5 Hardtop

There is no way I'd consider a C5Z over a C6Z unless the C5Z had the 500+ HP/TQ and the gearing of the C6Z. Save your money so you don't have to upgrade again to the later model.

First gear is ridiculously lame in either car, the idea GM had was to gear it for skip-shift (CAGS) to work so you could shift right into 1:1 or 4th gear.

When looking at the graphs in this post comparing the gears, keep in mind the C6Z will put you in your seat for a longer period of time. However long it takes to span about 1,000RPM is how much longer the gear lasts since redline is 7K in the LS7. The rush lasts longer. It pulls so much longer and I absolutely loved that. A 3rd gear pull to redline is so fun, you have to try it!

phloozy

Well i pulled the trigger on a 2003 c5 z06. Excited to join you guys. Now to get a proper AS setup.

Solofast

The C6 is "on paper" faster, but in reality it isn't as different as one might think.

If you look at the peak torque in first gear multiplied by the gear ratio the C5Z and C6Z end up with a very similar number. The reason is that's about how much power you can put down so if you have shorter gears and try to accelerate faster all you make is smoke...

The problem is in an autocross you're most of the time turning while you're trying to accelerate and the bigger power doesn't mean that you can use it to good effect. Most of the time coming off of corners in second gear in a C5Z you can't plant your foot like you could in a C4. If you try you're going to end up looking out the side window at where you are going, and that is generally the slow way around a course.

So yes a C6 has more power, but there just aren't may times that it can be used to good effect.

My LT motor C4's had a lot ore power than Roger Johnson's automatic C4 and I had a lot more rear wheel torque in second than his automatic. Every time we would pull from 4,000 rpm to redline in the LT cars I'd gain almost a half a second on the older cars, but the automatic cars were faster in the corners and that was hard to make up with more power.

The C6 should be faster, but it isn't going to be by much because you just can't use that extra power unless it's a pure straight and those are few and far between in an autocross.

C5 Hardtop

That is a beauty! Exactly like the one I had, minus one year. I had the '04. Careful with the 2-3 powershift on an uneven road, its easy to swap ends!

talon95

Real world results certainly don't suggest the C6Z is faster since the C5Z won both AS and SSR last year.

MidOhioZ06

Seems just like SSR, it is close enough (c5z/c6z) that the driver can make the difference, or a bit course dependent perhaps? I would think if you are looking at autocross in a vacuum... c5z makes sense... if you are living with it as a fun street car, or are wanting to do PDX/HPDE/track days as well, the c6z is the best of both worlds. Just my opinion after driving both generations, and settling on a '13 z06 to fill the fun street/track/autox car in 1 vehicle.

Bill Dearborn

It has been a while but I went from a C5Z to a C6Z. On the courses I ran the way to run the C5Z was to get out of low gear ASAP and run the course in 2nd. Much better on and off throttle control which let you steer the car better. With the C6Z the car didn't seem to come off slow corners in 2nd as well so I ended up just leaving it in 1st most of the time. That did lead to some interesting off throttle situations where I got a little more trailing throttle oversteer than I wanted. The up side was I could run almost every course in 1st gear so there was absolutely no shifting. I ran a fair number of Auto Crosses on Go Kart tracks and one of the great things about them is you could compare lap times from car to car from year to year (dependent on environmental conditions). Neither the C5Z or C6Z was as quick around a couple of those courses as my base level 86 with 230 HP and a 4+3 tranny. On one in particular the 86 turned a 123.5, the C5Z turned a 124.5 and the C6Z turned a 125. Of course that was over a period from 1996 through 2010 but basically those times were for the same track layout, same ambient temp and dry conditions. The only things that changed were the cars, tires chosen for each car, asphalt condition and my age.

Bill

MidOhioZ06

Ran my first national event in the C6z, still with temp tags


Over 80mph in 2 places, ended up 1st after day one, slipped to 2nd after day 2 (coned away the win). I'll post video links here for those interested. Congrats to Mark Labbancz for finding the time day two and staying clean for the win at the Wilmington Champ Tour.


Off to lose to Daddio next weekend at the Wilmington Pro.

phloozy

I'm local to daddio.... safe to say I wont take home local trophies

MidOhioZ06

only way to get better is to play the best... otherwise mediocrity sets in, seem to see it too often with those guys who are 'fast' locally, then come out to where the real competition is and they fall apart. I'd love to have someone like him local to push me and learn from watching.

phloozy

Yeah I am really excited about it!

MidOhioZ06

First real competition runs with the c6z this past weekend at the SCCA Wilmington Champ Tour.... 1st after day 1 out of 14, fell to 2nd after day 2. I won't complain especially still on temp tags . Congrats to Mark in his c6 Grandsport on the win.

phloozy

Damn 73 in 2nd! What does the c5z top out at? My first event is this sunday

conemark

The C5Z's on Hoosiers top out around 68 MPH. I would guess with a similarly sized Rival S, you're going to be in that same ballpark.

Good luck getting to that speed locally and divisionally. Wilmington is as open as it gets on the Eastern half of the United States as far as sites go. If you come north to The Meadowlands and run with NNJR or south to FedEx Field with WDCR, you might touch the mid 60's.

phloozy

yeah I am not actually worried about it. I have done a few NNJR events. Pocono raceway infield event hit hit like 85 lol

QKSLVRZ

Nice c5z you bought, I enjoyed my 02 a lot. It's song sounded better than my 13gs, but I think the 13 is faster.

phloozy

Thanks, just got these mounted for Sunday event