Autocross questions
 

First of all I fully agree that the best way to get better at autocross is to become a better driver first then mod my car. However, I have the attention span of a gnat and I cant help but tinker with everything so .... The general consensus seems to be sway bars, better brake pads, stainless brake lines, and of course good tires are the basic mods. I wanted to find out (in regards to autocross specifically) what other mods I might need to consider. For instance, the runs are so short I am not sure an oil cooler would be needed. What other ideas or age advice do yall have? Thanks!

If you are concerned about classing then there aren't a lot of mods you can make and still be in stock class. The main ones are, front swaybar (not rear), tires (any approved DOT tire including grooved slicks), dampers (but not springs). But like you said the best mod of all is the driver!

Oil cooler is not permitted (nor necessary) in stock class, it would bump you to street prepared.

OEM brakes (pads, rotors, lines) work great for autox IMO. An oil cooler is not necessary, if the temps start getting too high crank the heat on defrost and open the hood between runs.

Were the 2012 changes approved? Allows one swaybar change either front or back.

You may want to look into an oil cooler just because and forgo pads, lines ect. I know my car between runs was getting up in the 230-240 range. I feel the car does loose some power when it gets above 180-220 range. I have kw v3's, camber arms, intake, exhaust, upgraded brakes, the only thing I didnt do was an oil cooler thinking for auto-x I wouldnt need it. I was incorrect.

How do you like the kw v3's? I am very interested in those down the road. Which sways do you have?

I didn't see it in the current rule proposal listing, I will ask.

The power loss is from heat soak, not oil temperature. There is nothing wrong with oil temps in the 230-240 range. To vent some of the heat you can turn on the A/C with heat, and pop the hood. The stock air intake is plastic at least which helps to resist the heat.

Looks like it made it into the final draft. Approved by the BOD at the Oct meeting and noted in the December newsletter.
http://scca.cdn.racersites.com/prod/...ck-dec-bod.pdf

(Page 6) ITEM 10)
Change 13.7: 13.7 ANTI-ROLL (SWAY) BARS
A. Substitution, addition, or removal of a single anti-roll bar and supporting hardware (brackets, end links, bushings, etc.) is permitted.
B. Substitution, addition, or removal of an anti-roll bar may serve no other purpose than that of an anti-roll bar.
C. The use of any bushing material is permitted. A bushing may be implemented as a bearing.
D. No modification to the body, frame, or other components to accommodate anti-roll bar addition or substitution is allowed except for the drilling of holes for mounting bolts. Non-standard lateral members which connect between the brackets for the bar are not permitted.

Comment: The origin of Stock sway bar rule was an allowance to improve vehicle dynamics at a time when sway bars
were not commonplace in new cars, and RWD was the most common layout in the automobile industry. FWD and AWD
are common today, and throughout the years there have been comments pointing out that FWD cars would benefit
more from a rear sway bar change. In an effort to broaden the field of competitive vehicles across the entire range
of the Stock classes, the SAC would like to introduce the option of changing or adding the front OR rear sway bar.
The committee believes this promotes the core values of the club by increasing participation with broader choices of
competitive models, improved tire wear and improved handling for specific vehicle drive trains.

Yes you can replace either the front or the rear sway bar but not both. You should still only change the front on the 370.

If your only going to do one mod for auto-X, I suggest a set of Hoosier A6's.

Although, now you are going to need a separate set of wheels and street tires to get to the event. Unfortunately, your extra set of wheels will not fit in your Z.

So now you need to convince your wife/girlfriend to wake up at 5:30 a.m. and drive your wheels to the event and waste her entire day sitting around in the heat. Ok, that won’t work…

In the alternative, you can fabricate a custom tow hitch through the rear back up camera block off. Then you need to buy a trailer to haul your wheels. That’s a little complicated and expensive…

Just buy the damn sway bar…

:tup:

Haha Res that's my primary course of action:'convincing her to either autocross our MKV GTI or drive the GTI with a spare set of tires for the Z.

Either way it should be win win for me unless she goes out there and gets frustrated with the heat or running for cones.

The only way your wife is going to go is if she meets another wife there and they head off to go shopping...

First determine what class you will run. If you run stock Just do front swaybar and get set of Hoosier A6's or new Good Year DOT R AX compounds. Optimize alignment best you can. Listen to the guy who was 4th in Nationals one year.

If you dont care about class then good set of springs and dampers, front swaybar, nice set of 18x9.5 fronts and 18x10.5 rears. You can run 295 A6 up front and 315 in rear on those wheels. No clearence of spacers needed.

Finally get a good LSD like OS Giken.

Leave brakes alone - the stockers are perfect for AX. Contrary to popular belief you dont want track brakes on an autocross car. If you live in cooler area dont think you will need oil cooler however I was really not happy with temps of my car just with spirited street driving. I couldnt stand to see spiking temps so installed a cooler on my car.

I'm probably just going to run on my RE-11s. I'm thinking I'll have to run in CSP since I have a catback and oil cooler. Running in stock in Hawaii two years ago was awesome. There was an RX8 running on A6s which made for great competition during the season.

I'm looking forward to get back into autocrossing!

Re-11s are solid for autox, I drive an hour each way to autocross on mine.

ASP....not CSP.

Yep ASP for us 370 z drivers.

Whoops forgot about the change.

Yeah it's been awhile. ASP as in GTRs and Vettes? Anyone have a 2012 classification listing?

ASP for Nismo, BSP for non Nismo

Incorrect. ASP specifically states all 370Z. They are only differentiated in the stock classes.

No vettes in ASP now. SSP was beefed up to include the GTR and ASP mostly resembles old BSP with Porsches (minus current turbos), Evo/Subie, and that GXP.

Now that you have me looking at it again, it's not as bad as I thought. Maybe I'll be up to ASP before the 2013 season. Need that camber on the track!

Eh that's not too bad. I'm competitive but not to the point where I won't enjoy the race and participation.

All 370's are in ASP as mentioned. ASP is Evo's, STI's, skystices, and franken-boxsters. The 370 wouldn't be separated in street prepared.....that's why we have update/backdate in our rule set.

Oh sorry

Square vs. Staggered?
 

Any thoughts about running a bigger staggered setup vs. a square like 285/35/18's on 18x10.5 rims w/ 25mm spacer in rear? (uh oh ...)

Not lacking for power, the trend is to run as much tire as possible. Shamu, who is the most serious ASP contender we have, was going out to 12" in the rear.

I'll have 18x12's and 315's on all 4 of my 350 in the very near future, but will only be on 285's (18x10.5's) for the Dixie Tour and DC Pro. I have a set of sticker 285's to burn up.

It a heavy car that needs a lot of tire but it needs it more on the front. Running a staggered set-up can only result in lots of understeer. I think the trick will be fitting 315's square without having to cut/flare the front fenders.

I have decided to stay in Stock Touring category. I currently have stillen front/rear sways so I am going to put the rear stock bar back on and set the front to full soft for now. I have a non-sport touring model with the 18" rims and I need recs for a tire setup:

Option 1: keep stock sizes front/rear ... Seems to be limited in tire choices
Option 2: keep stock rims and upgrade tire size ... Uncharted territory for me as i have little knowledge of offsets, sizes, etc. (anyone have a setup that really worked well?)

Any comments appreciated!

Personally I would do at least 255 in the F&R

So what size tires for stock 18 inch rims front/rear (ie. touring nonsport) would you guys rec for autocross? I'm not sure what options are available that would be reliable and allow me to have a better selection of tires.

Curious what you are basing this on? I have been driving prepared cars etc for a long time and well setup 370z on staggered setup is completely nueteral from what I have seen. I experience very little understeer with 295/315 stagger. I think for average ax driver staggered will work fine if you have flexibility to use differnt suspension setup than stock.

I don't think shoving a 315 under front is going to accomplish much and for people in cooler regions I'd argue solo driver will have issues with getting that much tire warm.

I will be experimenting however I don't think a well setup car on mild 295/315 stagger will see as much understeer as you think. If anything my car tends to have a little oversteer. But I base this from running mostly cool venues as a single driver. Just wish more serious ax guys were trying SP/SSM mods.

A two driver car on warm surface may in fact benefit from 315 upfront. But honestly if I go to 315 front I'm going to 335 rear.

sCCA just announced a road tire class for stock cars that will happen at National tour events. All rear wheel drive cars will run in an indexed class. Given 370z is CS you would have favorable pax. This might be perfect timing for you. Just need to find good street tires that fit your wheels. Not sure what tire would be best?

Shamu,

I am thinking of going with 245/45/18 up front and 275/40/18 (base, stock 18" rims). This will keep a staggered setup with bigger tires than I have right now.

For tires, I am considering trying the Continental Extreme Contact DW. They have gotten some good reviews:
http://www.modified.com/tech/modp-09...s/viewall.html

And they are about $800 for four corners (including shipping).

Since this is my first foray into autocross I don't have the skills to push the car hard enough to make (in my opinion) a big enough difference that I would need to go with a much more expensive tire.

In regards to sway bar settings ... I have stillens up front and rear ... any suggestions regarding stiffness front vs. rear?

I think the conti extreme contact DWs will be okay. I have them on my MKV GTI and they put up pretty good with my very spirited driving style. They progressively give out but that might change on a RWD setup.

Next weekend is the first event in my area. I signed up for the novice day just to get some more seat time.

Is everyone just using vinyl for numbers? I really don't want to use blue tape. :/

You really have no tire options in your size short of the RE-11, which are way overpriced at $310+. The only thing you might want to think about doing is to go with a smaller size, Kumho XS can be had for about $800 if you are willing to run a smaller tire.

245 won't be enough front tire for autocross.

I'd reccomend Hankook RS3 in 265/35/18 front and 275/35/18 rear or even 275/35/18 front and 285/35/18 rear. Hard for me to say what will work on your car in bar department as I don't know what else you have but 370 needs lots of anti roll especially with stockish camber settings so I'd start with at least mid settings and then experiment.

If someone were to hear my setup they'd say no way would it work for ax. I have huge 35mm front bar and 1000 lb front springs with stock nismo rear bar and 450 lb rears. I spent lots of time on camber and toe settings but you can't do much about camber in a stock car.

Is the 370Z still CS for stock classes? My local region told me I was BS. I ran against a Subaru WRX STI that put up one heck of a fight throughout the day and edged me out.

Going by the 2011 classification list it states the Z as CS.

Also any tips on psi settings for the RE-11s? I chewed the fronts up a good bit on the course we ran but then again that was more than 15 runs on a 25-30 second course.

I just went to 18's... I am committed to ASP. I have 18x9.5 +30 (f) and 18x10.5 +15(r) with hoosier A6's 275's up front and 315's in the rear. This is an interim for spring (less heat in tires) until summer where I will bump up to 295's in the front. I'm with Shamu...you need a bit more tire in the rear despit the desire to be square.

To the point of this post and thread....other than seat time....tires,tires, tires. I figure A6's are good for 1.5 -2.0 seconds on a 45-60 second course.

Who will I see at Nationals this year....I will be there in ASP. side note - get a co-driver.....it's a great mod and it does help the budget!!!!!!!!