Auto-x

[xantxp5x]

This sunday I raced my pro5 completely stock in an auto x event.
Had such an amazing time and i intend on going and becoming part of the auto x club. I ran a 46.84 on the course which i was told was really good for my first event. I just wanted to comment on how UN-psyched i am with the dunlops that came on the car. I was coming through this big sweeping turn and every time the tires would screech out and slow me down. REgardless my p5 ran really well and i had a great time. I suggest all my fellow mp3 and p5 owners from jersey and NYC to come on down. Get at me if anyone feels the same way about the tires.

[ZG77_OzZ]

That sounds like alot of fun..

[122 Vega]

After six years of autocrossing, I'll tell you your first upgrade should be Kuhmo tires! These will make a bigger difference than any other single mod. Don't focus on HP, make it handle.

Britt

[bradspeed]

Wish there was on auto-X track in my area. In case there's one that I don't know of, I live in the Springfield MO area. If anyone knows of one within a reasonable distance (100mi. or so) please let me know. I would love to try my skills on a real track!

[gotdlife]

Check this Brad.

http://www.kcrscca.org/

I am in Jefferson City so no place really close to me. I have friends in KC so would prolly go up there for it. I am sure St Louis has same time of thing.

Doing a SCCA Solo II this spring would be a ton of fun i think.

[bradspeed]

AWESOME!!!
Thanks Jason for the info..
Maybe we could go to one at the same time.
I would love to see your MSP.
The local dealership hasn't gotten any in yet.
Every time I ask when they can be expected they always say "by the end of next month".
I would love to buy one but I just purchased my P5 last July so they would probably rape me on my trade-in.

[xantxp5x]

i actually cant stop smiling i had sooo much fun today. I got some questions for people who have autocross/ racing experience. I want to get a good tire and wheel selection for racing. Should i get 16" or 17" and is wider better??? also I know lightwieght is good. What about suspension will coilovers make it handle better? I want to get the ground control with the eibach springs will that help? or is it just for show??? Get at me!!

[rowan]

For wheels: smaller, lighter, wider
For suspension: start with adjustable struts before anything else

Also make sure you play around with tire pressures a bit to adjust the handling before you go sinking a lot of money trying to fix things that aren't really broken.

[scapamouche]

Before you buy ANYTHING, learn to drive your car at its current limits.

I've been autoxing since 1996, and one thing I've learned in that time is to go in steps: learn to drive to the maximum extent each time you do a mod, THEN do the next one. AS someone with no prior experience, in the long run, you will be better off with the car stock until you have enough experience to know exactly what you want your car to do and what to do to get it there.

For example, it took me almost 18 months to get my Celica into the shape I was finally happy with. In the San Francisco Region, I had one of the top cars in STS, because I had taken my time, and done things right.

I bought an Orange MSP yesterday, and I don't expect to start the mods for about 6 months, at a minimum.

That said, what you do depends on what class you intend to run in. If you are in the STOCK class (HS for a P% with the SCCA) you cannot make many changes at all: Shocks, front swaybar, cat-back exhaust, and tires. YOU MUST USE STOCK SIZE WHEELS!!!!!! That means SAME diameter, Same withs (+/- .25 inches) and same offset (again +/- .25 inches) DOT race tires are a good idea, and essential to be competitive in stock, but you should learn to drive at the limit with the stock tires, THEN put on r-compounds, and you will be better prepared to take advantage.

If you want to run in STS, wheels and tires are easier to work with: no diameter limit, 7.5 inches width limit, and max tire width of 225mm, with a treadwear of 140 as a minimum. Most of the really fast STS cars run on 15" Falken Azenis or BFG KD tires. I myself used the Falkens: AWESOME dry tire, great in the wet until about half tread, and CHEAP ($70-75 each for 205/50-15) Mods for STS are also easier: Intkaes, exhaust, full suspension, short shifters and the like. STS is more friendly to someone who wants to modifiy their car, but stock is better for a beginner if he hasn't made any major mods yet.

Good luck, and welcome to Autox.....

[cjstringer]

Run stock. I did, and I love it. I'll be stock again this year. Won my region first year out. I have the MP3, but the P5 should be a good HS car. I ran street tires for the first 2/3 of the season. They are much better than you think, the key is getting to know that SLOW IS FAST! If your tires are squealing and breaking loose, slow up a little and let the car do the work. Don't push the tires into submission. :)
Most of all, HAVE FUN! I can tell you already have the bug. It's a great time if the people in your area are a nice group. I've met some of the nicest people I've ever been around over the last year.
Good luck, and hit us up if you have any Q's!

[scapamouche]

What HE said :D

Another nice thing about running on streets for a while is how much faster and better the car will feel once you finally master the streets and move to r-compounds. I really appreciate the R tires now more than I would have if I'd run on them from the get go.

[xantxp5x]

i just wanna go ahead and say... I LOVE THIS F***ing car... everytime i get inside it I smile. I cant wait till i pus some money aside so i can jiuceher up and get her at the level she deserves to be. Also regarding the AUTO X as far as tire presure goes what should i run for the next time ?? Get at me.

[scapamouche]

Stock tires, right?

In general, you want to set the FRONT tires so that they don't roll over onto the sidewalls in turns. To do that, you'll need a pretty high pressure (I used 45+ on the stock Yokos on my Celica when I got it...) and you'll want some chalk or white shoe polish. I'll explain the procedure below:

1.) set your tires to a beginning value. (I recommend 40-45psi)
2.) Mark on the edges of the tread and over onto the sidewalls with the chalk or polish. Mark it so you can tell after a run how far over the edge of the tread onto the sidewal your cornering forces have rolled the tires.
3.) Go run!!!
4.) After the run, look at how far down the sidewall the polish has been worn off. Ideally, the edge of the polish will be right at the outermost edge of the tire tread blocks.
5.) If the tire rolled over too much, raise the pressure 1-2 psi and try again. If the wear did not reach the edge of the tread, then reduce pressure and try again.

All of the above applied mostly to the FRONT tires on a FWD car. Now the hard part: the REAR tires.

6.) Once you have the front pressures set right, then set the rears. What you want here is to set the rears so they have the right amount of grip to give the car the handling characteristics you want (i.e. how neutral, understeering or oversteering you want.) Start with the rears at the SAME pressure as the fronts. Then take on of two options: raise or lower the rear pressure to get the car to rotate how you like. In the vast majority of FWD cars, equal pressure front and rear will cause understeer. By adjusting the rear pressure, you can adjust the balance of the car. This is an ART, not a SCIENCE and there is no set way to do it: it's all up to choice. In general, though, the larger the difference (in either way) between front and rear pressures, you will tend to see more oversteer. The rear end will tend to rotate better (or too much.)

When my last car was stock, I ran 45psi in front and 26-28 psi in the back to get the car to rotate more. I have seen other people get the same results with 45 psi F and over 55 psi rear. It's all up to you and your preference.

My advice would be to find someone experienced at the next event and latch on. Ask questions, get advice and learn how tofigure ot your own best setup yourself. AS you get experience, it will get easier, but not easy.

BTW, a better way to set the front pressures would be to use a pyrometer and measure the tire temp on the tire on the OUTSIDE in the LAST corner of the run IMMEDIATELY when you get back to staging. The perfect pressure for the tires is the one where the tire temperature is EVEN all the way across the tread. Riase pressure to get higher temps in the moddle, lower pressure for higher temps at the edges. Be careful, though: camber and toe play a role here: If you have little negative camber (the tires look like "I I" or even "\ /" from the front) then you will have higher temps at the outside edges no matter what you do....

But how many beginners have a pyrometer sitting around? I don't after several years.....

Have fun, make friends and have fun..... :D

[cjstringer]

As for tire pressures on the stock tires, I recommend about 45-47 in the front and 35 in the rear. Keep the rea from sliding out and gives good control. Remember, often times through tight stuff where you push a lot in a FWD car, slow is fast. Learn it. Live it. Love it. It works.
Good luck!

[PA_MP3_Man]

I can't figure out why a smaller wheel is better than a larger wheel. I always thought that a smaller tire wall is better for this kind of stuff. Course I"m just going to start too so I"m just getting advice too. So if you experienced guys say that a 15" is better than a 17" I"ll believe you, but I'll scratch my head as to why.

So if you run stock, you can't change anything right? Springs shocks, wheel size, strut bars, sway bars? THey either had to come with the car stock or not at all right? I'll have to look up the SCCA rules on modifications. But thanks for all the help you guys do.

[sleeper_]

pa_mp3_man, obviously low profile tires (shorter sidewalls) is better for handling.
as for the smaller diameter, i believe it has to do with unsprung weight affecting the performance of the suspension. ie with less mass being accelerated with the suspension, the more quickly it can respond to the road. And in the drag setting, it's effectively gives you a "shorter" gearing and weight makes a difference here as well.

[scapamouche]

For STOCK class, you can change: Shocks, FRONT Swaybar, Cat-back exhaust, and tires (DOT legal r-compounds are OK.) The wheels must be stock size (+/- .25 in for width and offset) and no added strut bars are allowed.

The smaller wheel is good for torque multiplication: it's essentially the same as putting lower gears (numerically higher such as 3.73 vice 3.42 differential gears.) It's not OK in stock to go with the smaller size unless they were available from the FACTORY with the smaller wheels: DEALER ADDED OPTIONS ARE NOT OK FOR STOCK!! The lower weight is also a factor: less weight to accelerate.

[PA_MP3_Man]

Ok, i gotcha, thanks. Well I think I'm pretty much ready to go and try to kill my daily driving tires in one day :). Happy racing to you guys. Good luck.

[cjstringer]

The stock Dunlops lasted through about 8 events for me. Then they were shot. Now I use DOT R-rated tires, but I'm glad I experienced the stocks first. I would have never understood the difference. It's well worth learning on the street tires. You'll also learn how to better handle your car in case you ever have to get a little aggressive. (Have to swerve to avoid an accident or get around something unexpectedly) GREAT experience for any driver.
The smaller tire thing, scapamouche hit the nail on the head. You can reduce rotational mass by 15-20 lbs at each corner. Less to stop, less to accelerate, and less to turn. All that mass adds up over time, and slows you down in the long run if there's too much.

[KzA]

hey...where in NJ do you auto-x?

[xantxp5x]

check out the website www.themclub.net. These are the guys that put on the even that I now partake in. They go down at Giant Stadium in one of many parking lots. the next one is sunday Feb 23 i'll be there again.

[scapamouche]

Another good resource for autox is www.scca.org then follow the links to the regional site for your area, and look for SoloII information and schedules.

[sleeper_]

cjstringer:

i believe i said what scapamouche said first :P
and i touched upon another concept about suspension that he didn't :P

i mentioned smaller tires effectively lowers your gearing and that the rotational mass is one thing in terms of having to accelerate it from a slower rotation but ALSO the suspension system responds "quicker" to bumps, irregularities, etc. on the road with lighter wheels

[cjstringer]

Sorry Sleeper, I'll check my quotes a little better next time! :)

[scapamouche]

Originally posted by sleeper_
cjstringer:

i believe i said what scapamouche said first :P
and i touched upon another concept about suspension that he didn't :P

i mentioned smaller tires effectively lowers your gearing and that the rotational mass is one thing in terms of having to accelerate it from a slower rotation but ALSO the suspension system responds "quicker" to bumps, irregularities, etc. on the road with lighter wheels

NYAH, NYAH, NYAH!!!!!! :D Bah Humbug ;)

[xantxp5x]

hahah i noticed that but i didnt wanna say anything. :p

[Allen]

Thanks for the detailed info/tips on autocrossing guys! Wonderful reading!! (thumb) Heading for my first autocross this weekend... can't.... wait...!!!!

[dolphin]

Let us know how it goes. Mine last weekend went fairly well but I was in the miata. My daughter was in the MP3 and she did OK as well.

[Newf]

quick question.

What's with the Kumho's?

I ask because I had a set a few years ago, and I thought they were the worse tires I ever put on the car. Even worse then the bridgestone they replaced. I never got any milage out of them, and the couldn't grip for shit.

I guess they got better recently

[JasonH]

Originally posted by newf
quick question.
What's with the Kumho's?

They're talking about Kumho racing tires (http://www.kumhousa.com/Racing/), not the run-of-the-mill everyday tires.

http://www.kumhousa.com/images/Products/Tires/EV700.jpg

[bellspeed]

what size race tires are you guy's running?

[HADA 11]

Run the smallest wheel that will fit over your brakes.

A smaller overall diameter whell tire combo will in effect give you a higher gear ratio. (The car will accelerate faster)

Smaller wheels tend weigh less then larger wheels (yes you can get light 17" or 18" rims, but they cost a grip). I'm not sure if you've ever heard of the term "unspring weight" but it reffers to weight that is not supported by your suspension. The lower your unspring weight is, the faster your suspension will react. If you boil it right down, the lower the unsprung weight the better the handling.

So small, light wheles are the way to go. Why do touring cars have huge wheels? To clear huge brakes.


Edit: I totally missed page 2 of this thread. Sorry about the repitition.

[dolphin]

cWhat wheels and tires I run depends on which class I am running and what the rules are for the class. Normally, I am running my Miata in the stock class so I run the stock size wheels with the Kumho V700 victoracer tires.

Right now, my daughter is running the MP3 in street tire class on a GS index. This means that she is running GS rules except that she can only run regular street tires. We have run the MP3 in FSP with 225/50-15 "R" tires on 7x15 inch wheels.

I guess my point is that you need to know the rules and what they will allow you to do.

[scapamouche]

Originally posted by JasonH

They're talking about Kumho racing tires (http://www.kumhousa.com/Racing/), not the run-of-the-mill everyday tires.

http://www.kumhousa.com/images/Products/Tires/EV700.jpg

Like Jason said, the Kumhos we're talking about are the Victoracer V700s and Ecsta V(?)700 race compound tires. They are one of the two dominant r compounds used in SCCA SoloII these days. The other option is from Hoosier, and there are also tires available from companies like Toyo, Michelin, Yokohama and BFG.

I personally have very little experience with R-compound tires myself: two autox two years ago with my Celica in STR (a now defunct class.) Most of my time has been in STS where there is a street tire requirement (enforced by having a minimum treadwear rating of 140 for any tire to be legal for STS.)

I think I'll be driving the MSP in STX here in the local region since I won't be around for a full season, and I want to hang out with all of my friends in STS, which runs at the same time here.

[rowan]

Since some MP3 guys and MSP guys have posted in this thread ...
I just noticed that the 5Zigen Fighter wheel comes in a 17x7 +50 mm offset, so there is another option for stock class wheels that are lighter than the RacingHarts. I like the Titanium colour.
http://www.wheelspecs.com/specs/wheelmodels/509

[bellspeed]

I'm planning on running in the stock Class. My problem I'm having is that the stock size for the MSP is 215-45-17 and the tire rack is not showing any Race compounds in this size. I also tried 205 -45-17 and they showed nothing. Will 225-45-17's fit or am not looking in the right place for tires?
Thanks

[dolphin]

bellspeed,
You are right. The two closest sizes I could find are 225/45-17 or 205/40-17. I am not sure that the first will fit and the second may be too small for the MSP. With the MP3, I was going to use the 205/40-17 but my daughter wanted to run in the street tire class.

[MSP Pro]

dolphin, bellspeed: I noticed the same thing, but I'm thinking of going with the 205/40-17 due to the smaller diameter: more revs per mile (875?) than the 225/45-17 (835?). Also, the recommended wheel size is 17x7.5 for the 225/45, where the 205/40 is 17x7.0 (stock wheel size).

I haven't been able to find a +55 offset wheel, though. While a +50 will work and is within the 1/4 inch allowance, what does it do to the steering geometry (center of the contact patch is moved 5 mm)? A wheel spacer 5mm thick would provide the added clearance if the brakes interfere, but doesn't fix the change in geometry. Anyone tried some +50 offset wheels and noted any handling differences?

[dolphin]

MSP Pro,
I have two sets of the stock Racing Harts for my MP3 so I can't help you with the off set question. The other thing you need to check is to make sure that the tire has sufficient load carrying capability for your car and use. With the MP3, the 205 is the correct section width and there is enough load carring ability to handle the car in autocross trim. You would not want to use them for trips with the car loaded.

[rowan]

Lower offsets mean the wheel actually sits farther away from the brakes so you will be fine. +50 is the best you'll get. As far as I can tell it is either get Team Dynamics Pro-Race-1 wheels and have them made to a +50 offset, or get the 5Zigen fighter wheels which are already +50.

A lower offset will give you a slightly wider track, and therefore a bit more stability but it will also slightly increase the feeling of torque steer.

The Dunlop SP9000 actually have a really high load rating which will be tough to match with other tires of the same size. (only 24" o.d. ) Although it may not matter too much if you are only using them for competition. What I would be worried about I guess is overloading the sidewall of the tire if the load rating is not high enough? Does that make sense? I'm not sure ... hehe

If you are only using the tires for competition, you have a bit more flexibility with the tire size vs. wheel size. Putting 225s on a 7" wide wheel probably woudn't be great for street but you could get away with it for competition.

[MSP Pro]

Rowan, thanks. I would be using the wheels for competition only, so I'd be going with the Kumho Ecsta V700. The 225s on a 7" wide wheel might tend to cup the footprint by pulling the beads in too far. Also, the 225s weigh 23.3 lbs each, the 205/40x17 weighs 19.2 lbs.

But when I look at the price of wheels and tires, it's way over $1000 which puts it out of reach for me right now. I think I'm going to wait and run my first season on street tires. I'll learn more of the subtleties of the handling that way before going to r compounds for that last 10%!