Well I am racing in class B, and while I always do well overall I never win my class.

Last race I ran a 68.02 against an averaged 71 sec track and FTD was 66.7 (C6 Z06 w. 335 hoosiers)

I came in 8th overall but 5th in my class loosing to mini's-S's with hoosiers and sti's with hoosiers.

I beat everyone else but the damn supercharged mini's and the damn modded sti's and they always have slicks. I am the fastest on street tires, so maybe I need to get slicks then.

Thing is I dont think you can compare these boosted cars and slicks to a 350z with springs and wider stock tires.

 

What track were you running on?

Perhaps it's the driver? Your setup? A combination of the two?

Or is it just autocross?

NASA rules are more tailored for a road course as opposed to an Autox course.

you're clearly a noob to racing....

 

get slicks...

 

No, don't get slicks.
All they do is mask your bad tendencies. Work with your current setup until you realize what on the car needs to be augumented to strengthen your natural driving habits.

 

this was auto-x.

I agree it would be different on a road course

 

Generally you will feel outclassed by cars until you get your car set up in accordance to the rules as best you can.... and that usually comes after you've learned what you need to do to help out your natural driving style. Are there any autox events near you that are SCCA affiliated? I'm not sure what mods you have but it's possible that you may be able to be in a class of cars that you're more competative in. I'm pretty sure I remember you saying you have a lot of audio stuff in your car... I hope you take it out!

 

well I have the spare tire out and I sub there so its no biggie. Front speakers and amp weight about the same as stock...no more than 5-10lbs more.

I looked at the results and the fact that I am the only one in my class not on slicks is a big impact for me, plus I had my strut bar off and front sway. I was in the process of putting on 350evo sways. We will see how I do with the sways on, strut bar on, alignment and maybe I will remove the sub.

 

There's a lot more than goes into a setup than just installing the parts. The good thing about our OEM FUSTB is that it's adjustable from the factory.
Have you gotten a custom alignment? That can also make a big difference, and it gives you a place to start as far as camber, caster and toe are concerned.
Tires are always the biggest factor for speed, but again the R-compounds really do mask bad tendencies.

How much fuel did you run?
What are your other mods?
What tires?
What pressures?

 

I know Fluid1 is trying to get you to think about how you drive which is appropriate. However if you are the only car on streets then you are giving away 1-2 seconds. If you want to be competitive then get a set of OEM Track Rays and some Kumhos. If this is for fun then just have fun and don't worry about anything but how well you do.

BTW, if you do go to a SCCA event it looks like you are in BSP. Then wheel size and most suspension changes are allowed. First350Z's posts in this forum about BSP setup will help you by showing what is working for him.

Warning: Once you go to the dark side of R Compunds you won't want anything else. They cause an addiction to G forces.

 

well yes I am 99% of the time the fastest street tire car out there. I am a good driver but always have room for improvement.
My local SCCA group has 35-40 sec courses which I hate. NASA has 60-75 second courses.

I really need grip to compete.

 

All accurate statements.

Being that R-comps are crack, I always recommend to hold off. I raced a full season of Tire class last year (BST) and I've got years of autox experience. (used to drive FWD in STS)

 

i have about 3 good years of auto-x experience, about 15-17 total events

 

Well that's not bad.

So.....

Mods?
Tires?
Tire pressures?
Fuel level?
etc.....

 

Then suck it up and get a used set of wheel. If budget is a concern, you can find used tires as well. Billyco just unloaded a bunch at a GREAT bargain. I think he wanted $400 for a full set of stockers with 245 stickies.

 

I have eibach sportlines...soon to be KW Varient 3's
350evo sways med/med
oem strut
245 front / 265 rear Bridgestone re50 130 tread wear
35psi F / 32 psi R
intake/spacer/exhaust for power??? hehe
1/2 tank of fuel (afraid of fuel starve under tight turns) could I use 1/4 tank??
1 10"sub in back but no spare so ~ = weight

no alignment after lowering

plan to buy kumo V710's 285 all around and mount them on two sets of rear touring wheels (03 touring wheels)

 

I would recommend a full tank of fuel. That way it's consistent each race, and you have the extra weight over the rear wheels to help out the OEM weak VLSD.
I would also recommend the same size tires all around for sure, for Autox.

On street tires I'd think that you were running too low of pressures at 35/32...
The Spare tire is actually 'better' for your weight because most of it's mass is behind the rear axle. The Sub (if it's an understrut thing) is more towards the middle of the car. If it's easy to unhook and take out, I'd do it. You can leave the spare out as well because your full tank of fuel should be fine.

You can run with the fuel level on ----- and not have any issues with starvation.
I did for a while before I tested with full fuel and it's certainly better with full fuel. Amazing that 150 pounds will actually help you on corner exit.

I can't recommend the KW Variant 3's either.
Sounds like a good plan for your wheels, as long as they don't put you in another class. IIRC, the Kuhmos are 10 points. Different-than-stock rims would be a penalty too, and yes, having 2 sets of rears is not stock.

As for alignment. You have just springs, so I'd go for maximum negative camber in the front. Shouldn't me able to even reach 2*
I'd go -1.5 camber in the rear. I like 1/8 toe out in front and 1/8 toe in for the rear. That might be a good base for you to start at.

 

Do you suggest this for the ability to rotate? I ask because I had been running a square set-up of 275s all around, and had considerable oversteer at corner exit. I made sway bar adjustments, which may have helped slightly, but the change was not as noticeable as when I changed to a 305 rear tire. I've actually induced a bit of understeer now, so need to dial back the sway bars to compensate.

Thanks for any additional input.

 

although I have never ran an Auto-x, in know in a HPDE or PDX it is A LOT more fun keeping up with, or even passing another car on sticky tires when I am on streets. It can be rather humbling to other drivers.

 

Great information. I am consistant with my times compared to the other drivers so I will go and and see how these change things. I constantly struggle with powering out of corners and maintaining grip.

What is a good reccommended tire pressure if I go out next week on the street tires???

What is the defining issue with the VLSD. is it slower in reaction than a clutch lsd? is there a night and day difference in grip?

Lastly I think no one will know I am running 18x8.5 as opposed to 18x8 up front since they are OEM wheels.

and why not the KW's? maybe stance or BC??

 

What shocks are you on? What tire pressures? Usually an adjustment to the shocks and pressures can make that difference.

I generally recommend the same size tire all around because, in my experience, it has taken away that pesky understeer. On 275/17 Kuhmo V710's I run 38f and 33r with a full fuel load and the Koni yellows set to full stiff on all 4 corners. Cusco solid front sway on full stiff.