Wouldn't 255 A6's come in 1 point lower than 275 R6's? I would do that in a heartbeat.

 

Depends on your base tire in your class.

For a Z with a base tire of a 255, a 275 R6 would be +14 (10+4). A 255 A6 would be +13 (13+0).

For my Z with a base tire of 265, a 275 R6 is a +11 tire (10+1). A 255 A6 would be a +12 tire (13-1).

 

I am heavily considering running the 255 A6's. I just don't want to have to buy new tires all the time. I know the R6's last a little bit longer but I would like a comparison between the two as far as the life goes. I know they are much faster than the R6's. I'm trying to debate if it's worth buying them more. I guess I'll just have to win all the time to get free tires.

 

They are seconds faster from what I hear from the Corvette crowd in the SE region. But I wouldnt plan on running more than a few laps before coming in. SCCA racers may use them but they are usually getting close to cords after one 45 minute race. YMMV.

 

Always good to follow Hoosiers instructions. I have always cured my track tires - I run my race car up and down a mountain road before track days. LOL!

Curious is the NASA time trial series pretty good? I'm a long time Porsche club guy and we had club time trials. I'm looking for a new home since I have left the Porsche fold.

Is there a class for fairly tame street car like mine? I will only have a few bolt ons, LSD and hoosiers. And can I run without a roll cage?

 

Just noticed that the base class for the Nismo 370 is TTA.....not crazy about that at all.

 

I always pick the wrong car!

 

It's the land of C5 Z06's here....

 

No cage needed for TT, though I would recommend a roll bar at least. The faster TT classes get up there in speeds, better to be safe than sorry. You will love NASA, great nationwide organization!

 

I noticed that too not to long ago. I know it claims 350hp, but it's bit heavier than a C5 Z06 and 55hp shy too.

The C5 Z06's are TTA*. My buddy that got me into road course racing drives one so I hear all about it. I would think TTB** would be a better fit for it or even TTB*.

The Nismo 350 is TTB I think.

 

Correct, the Nismo 350 is in TTB. I have to agree that the Nismo 370 is better placed in TTB. It is going to have nothing for a 3100lb 360-395whp Z06 in TTA on hoo hoos....within the allotted points.

 

Did anybody ring??? Hahaha

As far as the R6's go, breaking them in on the street is pretty much useless because you can't get them hot enough. You can do all the figure 8's you want in a parking lot but it won't get warmed up enough for the tire to break in. You could have gotten them heat cycled from some vendors.

Anyways, good luck at your event.

 

So I got some really good news from the NASA national TT/PT director about my reclass today. He is letting me stay in TTC as my base class and negating my engine mods as points so that is helping me out tremendously. I dynoed at 242whp at IP on their Dyno Dynamics a year and a half ago. Based on my re-class from the director I cannot go over 265whp, but that is based on a Dynojet so I think I will be ok. It might be really close, but I think I'll be ok. So now I have to make some pulls at a place here in town since they have a Dynojet to make sure. I just removed my headers a week ago and put my stockers back on because I thought for sure that I wasn't going to get base classed in TTC again. I regret it now, but that will help a little in keeping me below the 265whp mark. They were on the car when I got it dynoed before. I also cannot go below 3190lbs as my comp weight so that includes me in the car with my gear. I will be around 3220 with fuel so I'll be good. I just have to not let my fuel get too low.

I am really excited about this. I was putting down competitive lap times last year while I was still in HPDE 3/4 and I had no aero, coilovers and just running R-comps. I think I will have a good chance of doing very well throughout the season and possibly winning the region. It would be nice to have a victory for the Z. Nationals is in my home state this year too at Mid Ohio.

Here is a breakdown of my points:

TTC after dyno re-class to negate engine mods. I can get 39 points and stay in TTB. I cannot go below 3190lbs with me and tank of fuel. Also cannot have more than 265whp on Dyno jet.
+13 for Hoosier A6’s (255's square)
+3 for aftermarket LSD
+2 for sway bars
+2 for non OEM calipers (Brembo)
+6 for front splitter & air dam
+4 for rear wing
+5 coilovers
+4 for camber arms (had to remove the SPL’s because spherical joints add more points, getting different ones)
=39

 

I still contend that the OEM brembos should be 0 points. They are the same as factory brembos from evo's/sti's. You may be close on power. I dyno'd at 262whp on a dyno dynamics (uncorrected...like IP) and 282wh on a dynojet. Just make sure the results are in SAE not STD. What coilovers are you using?

 

While I agree, the rules are written for all cars. If its an option, its points. If you want the most for your 2 points, you gotta go for Stoptechs. I think the Brembos are plenty though at this level, as long as you run a good rotor and pad combo.

 

My main gripe is the track model is ttc base classed and has the Brembo's as standard. Why the discrepancy?

 

I emailed the TT director about the OEM brembos and he said that I do have to take 2 points for them because they did not come standard on my car. Anything that did not come factory on your vehicle other than replacement parts is not OEM in their eyes. The track model Z is TTC* and mine is just TTC so I am thinking the Brembos help add that one star.

Also, I agree that the OEM Brembos are enough too. I think stoptechs would be overkill for what I am doing. Especially since I have already removed about 120lbs out of the car and will probably remove more when I pull the motor and rebuild and go to TTA. I don't see a need to get bigger brakes if I continue to take more weight out. I run blank rotors and Carbotechs.

I am using Zeal Function X coilovers.

 

With proper cooling the brembo set-up is more than adequate for a TT car.

 

You might want to look at getting custom frame-side bushings/mounts made for the SPLs. A local guy has made some in the past. It's a fairly easy swap, since the sphericals just screw into the arms. All you need is the right side thread, some tube to hold the bushing, and bushings. You can do custom hard rubber or make the tube to hold the OEM bushings.

Probably cheaper/stronger overall solution than most of the other A-arms I've seen out there. The SPL camber/caster adjustment system is pretty robust.

 

That's a good idea. I will definitely look into that.