OK. So this was my first time out with my Vette. I have run many times with my 2001 Audi S4, but this was the first time with this car.

All in all it was awesome! The, oil temp never got above 250. The water was a bit toasty at around 225 to 235.

The track I was running is High Plains Raceway just outside of Denver, CO. It is a 2.5 mile course with lots of elevation changes and a pretty long 3000+ foot back straight.

The car is a Z07 car with Nitto NT05's and just a Miniram with a cat back exhaust and removed main cat. Other than that it is stock.

It was very interesting to reel the C5/C6 guys in at the corners and then lose a few car lengths in the long straights.

I have attached 3 in car video links, or do a search on L98 High Plains. Lots of Porsches, C5/C6's, and a few oddballs here and there as usual.

Enjoy the videos!


http://www.youtube.com/watch?v=kctd82_sDQ8

http://www.youtube.com/watch?v=iBhUGJfNco4

http://www.youtube.com/watch?v=gsxyxfXxaiQ

--Calvin

 

cool

 

Too much fun !!

 

 

 

 

Love it white is my favorite color anyone ever use n20 on the straights at theas

 

Great videos - More please

 

For safety reasons most groups will not allow n2o on a road course.

OP - now you've done it. Prepare to spend lots of time on the track

Yea, its amazing how we can hang with them on the turns with 20+ year old technology

 

Now that's a TRACK !!!!
That's what's all about
Cool video !

 

Well done, thanks for the videos
That L98 runs well!

 

Nice!

 

Awesome!

 

What kind of lap time difference is there between your S4 and an old C4 with a passenger riding along?

 

Great clips and great driving! I especially liked the footage in the third link. You took that silver C5 out in the turns. Do you think the C4 outhandles the newer Corvette, or is this just a case of a less-skilled driver?

 

The C5 has a little better suspension geometry.
On the C4 little things like more negative camber up front. Getting it can be a struggle. Before I did my suspension rebuild the best I could get was +0.1 degree, after the rebuild I can get to zero. I have to go to offset bushings (no points) or adjustable A-arms (lotsa points, bumps we up a class)

Probably a lesser skilled driver in that case

 

My suspension is totally stock and it had no problem getting to -1.0 degree camber, I just had to give up a bit of caster - at +5.1 degrees right now.

My opinion is that the two handle differently, but very close in performance - not nearly the big difference everyone would have you believe.

Both cars have a 50/50 weight distribution, but the way they achieve them is different. The C5 has kind of a polar mass set-up with two large weights - transaxle and engine more spread apart providing the 50/50, whereas the C4 has everything scrunched towards the middle with very little mass at the extreme ends of the car. The C4 is definitely more "organic" to me, and much more "tossable" due to this different weight distribution.

It also depends on what you mean by a "C4." If you compare a Z07 packaged 1991 car like mine vs. a 1996 base car the suspensions are WAY different as far as spring and shock rates go. I will tell you that there were no stock C5's or C6's of any type, including Z06's & ZR-1s there that day that were making much, if any, time on me in the corners - straightaways is a different matter with my car still only being at about 280 HP at sea level with the slight engine mods I have done.

There is always the possibility that it is driver, too, but I am certainly no professional driver and that was my first time at the track with a Corvette, so lots of room for improvement.

To answer somebody else's question it was about 2-3 seconds a lap faster than my S4, which I also have a video of on YouTube. However, that was after probably 350 miles of track time with the S4 vs. 50 with the Vette.

I will say, though, that I walked away very happy with my decision to purchase a C4 instead of a C5 after my first track day. The car is way easier to work on due to the clamshell, I like the tight confines of the interior compartment and seats, and that you feel like you are in something different vs. an interior that looks like it came out of a Grand Am, and I paid $5700 for the car, which you can't even come close to on even the base model of the earliest C5's. I don't want to start a C4 vs. C5 war, but those are just my opinions - to each his own.

 

Thanks for the Vids.

Good looking laps, corner entry & throttle apply before corner apex look good. Knowing the track & seat time on it help along with a decent handling car.

She's a bit loose at times, may be hard tires but I think the fuel tank location is the problem with assy C4's. Its mounted to high & to far aft. If its a track only car a fuel cell mounted where the spare tire lives would help tighten up the tail.

GL

 

Thanks for the comments. The car is not quite that much "track only" That is an interesting point, though. The tires are NT-05s, so not racing slick soft but not exactly all seasons either One of the problems I think may be that the alignment shop put a slight toe-out in the rear when I asked for a slight toe-in. I just noticed the mistake right before the track day so I had no time to fix it.

 

Inexpensive toe plates here: https://www.lefthanderchassis.com/v2...oduct=15379500

Or you could fabricate a set.

If you purchase the plates check them against each tire. You looking at the tire squat radius which is the "bulge" at the bottom of the tire with the vehicles weight on it.. If the bulge is excessive the plates will not sit flat against the tire & effect the toe reading. Removing some material from the plates @ the bottom center will work.

Rear camber can be checked with a 24" level that has digital read out. No worries about caster on the rear. Check the camber either fore or aft of the wheel/tire vertical center. The tire squat radius will also effect this reading.

Have some Vette track alignment specs, will look for them.

GL