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Discussion Starter · #1 ·
Hey everyone,

First thing, I have been saving up to buy go fast goodies for my car for a while, but just recently (the past month), I decided I didnt need to go any faster in a straight line, I want to become a better driver. So I have decided on buying auto-x/road racing goodies.... Now before you say I need to just drive my car as is, I realize I will not be able to push my car to its full potential now. I know my car is more than I can handle right now for autocross, but I have my mind set on this... and this money is burning a hole in my pocket waiting to be spent on my only campanion (my Z) :biggrin:

So after doing some research for a while now, I have come up with this...

1. RSR's Ti2000 springs
2. Koni "yellow" shocks
3. Hotchkis sway bars
4. Injen CAI
5. Kinetix SMOG legal hi flo cats (have to pass smog to drive on base)
6. Top speed cat back
7. Z1 motorsports 14'' Akebono big brake master kit

now with that said I am still up in the air about getting...

1. 4.083 final drive
2. New lighweight wheels, and sticky tires
3. Recaro reclining lightweight seats with 4pt harnesses

And with my understanding, any engine mods i.e. plenum spacer, lower plenum etc... will bump me up a class, as will a new LSD...

so my question here is...

Do any of you guys have any suggestions, likes, dislikes, for the setup?

and

Will any of the things I want to get for the car bump me from the CS class to the BSP class? Do I need the stock wheels that came on the car to remain in CS?

Thanks for all answers/suggestions/input etc,
Kyle
 

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My personal advice. Bear in mind that I don't know the class rules for AutoX, so my suggestions don't take that into account.

Also, my experience is in road racing courses rather than AutoX. Your setup does vary between the two, due to the tightness of the former and the longer duration of the latter.

I decided I didnt need to go any faster in a straight line, I want to become a better driver.
:thumbsup: That's the attitude. Long term, its a better investment to throw money at improving the driver rather than the car. Unlike parts, skills are transferrable to any vehicle you drive.

Now before you say I need to just drive my car as is, I realize I will not be able to push my car to its full potential now. I know my car is more than I can handle right now for autocross, but I have my mind set on this... and this money is burning a hole in my pocket waiting to be spent on my only campanion (my Z) :biggrin:
Here's my first tip. Do a few road racing days first. A modern road car is built to suit as much of a target market as possible. The point of modification is to make the car suit you better, and until you know what the car's lacking you won't know how effective your modifications are for your purposes.

Also, mod money pays for a lot of track days and consumables. Trust me when I tell you that once you get into road racing, you'll be chewing through consumables like nobody's business. Constantly replacing tires, brake pads/rotors/fluid, engine oil changes, etc will put a big dent in your wallet.

Also, what's your usage of the car? Is it going to be a weekend-only car that only gets used at AutoX/road racing events, with its only street use driving to the venue? Or is it a car you'll drive every day, and used for motorsport once every few weeks? Do you care about the resale value of the car? This will affect what you can and are willing to do.

Now, down to your mod list:

So after doing some research for a while now, I have come up with this...

1. RSR's Ti2000 springs
2. Koni "yellow" shocks
I'd personally get a coilover kit rather than buying the springs and dampers separately. At least you know the spring and damper rates are properly matched, and it gives you the ability to height adjust to corner weight the car.

That said, I do like the Koni Yellows since the adjustment point on the rear dampers is on the side of the strut. A lot of dampers have the adjustment point on the top, which means you need to either cut through the trim or pull the whole thing out.

I use Tein Flex since the EDFC allows me to adjust the dampers remotely, so I don't have to cut holes nor pull them out. However, I find them a bit too harsh for the rough Australian roads so you should consider what your local area is like.

If you have the budget to pay someone to custom tune them for your conditions, I'd recommend it. I know when I rebuild my Flex's, I'm dropping my spring rate and getting a local specialist revalve the dampers to suit.

3. Hotchkis sway bars
They come highly recommended, and being adjustable is good.

4. Injen CAI
I wouldn't bother from a performance perspective. The OEM airbox is actually quite well designed, so using a freer-flowing K&N panel filter will give you better performance than most aftermarket intakes.

If you want intake noise, however, go for it.

5. Kinetix SMOG legal hi flo cats (have to pass smog to drive on base)
6. Top speed cat back
The Top Speed looks like a copy of the Buddy Club exhaust, which I've got. It's loud and droney at light throttle application, but if you can bear with it around town it makes a terrific noise at WOT. Most catbacks give the same performance on NA cars, so performance-wise its much of a muchness. Just make sure you don't get a true-dual as those make hardly any more power on peak, but sacrifice a fair amount in the midrange.

7. Z1 motorsports 14'' Akebono big brake master kit
For AutoX I wouldn't bother. Just getting a Stage 2 kit. Bigger brakes doesn't mean more stopping power, it just means more heat capacity. It also means more unsprung weight, which is a handling killer. If you're doing events that can't fade out a Stage 2 brake kit, then don't upgrade.

For road racing I would upgrade from the non-Brembos. I went to the 350Z Brembo package. I've only ever faded it once, and that was with the OEM pads / rotors and in the middle of Summer where the ambient temp was in the 90's.

1. 4.083 final drive
This boils down to where you're driving it. Every gearchange reduces acceleration on throttle, and unless you're really expert it can also reduce the stability and rate of your deceleration under brakes. The extra in-gear acceleration needs to offset this time loss. Unless you can max out the highest gear you use you might find yourself going slower.

On the road racing course I use the most, going from 3.5 to 3.9 has actually made me slower. With the stock FD I could hold 3rd gear around the entire circuit bar the main straight, but with the 3.9 I constantly have to change up and down. Since I don't max 4th anywhere, I don't take full advantage of the FD and it introduces more points of failure in my driving.

That said, on a faster course I might be able to hold 4th more, where I previously would have had to grab 3rd. On such a circuit I might be faster.

2. New lighweight wheels, and sticky tires
Very yes. Tires are the single best upgrade on a street car. They benefit acceleration, braking and turning.

Doing road racing also heat cycles the tires, which makes them go brittle and lose grip. You do not want to do that on your street tires, especially if it rains a lot in your area.

If this car is street driven you're better off abusing a set of dedicated track tires, and saving another set purely for street use. It means you can go very aggressive on your track tires (which will be noisy, not last very long, and have no grip when they're cold or its wet) and still maintain a set of street tires that are quiet, work in more weather conditions, and get decent mileage out of them.

Even if you don't get R-Compound or S-Compound tyres, depending on your class rules, its safer to not heat cycling your street tires, and even if you destroy your tires on the track you still have a legal set for use on the street while you save up for a new set.



If you're willing to pull out the interior in the car, do it. Weight reduction is a great "free" mod that benefits all aspects of a car's performance. Of course the car will be uncomfortable on the street with all the trim missing and the sound deadening scraped off, but it will drive a lot better.
 

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Discussion Starter · #3 ·
Wow, I Honestly cant thank you enough. ^^^This reply is exactly what I was looking for.

Also, my experience is in road racing courses rather than AutoX. Your setup does vary between the two, due to the tightness of the former and the longer duration of the latter.
I am Def leaning more toward Road racing than Autocross. I enjoy watching it more and riding with other ppl more. plus it has always been a dream of mine to be in Road Racing. the only negative is, I dont know if I am going to be able to make the Licence class date for this yr. So my thoughts were that perhaps auto-x would help prepare me for Road Racing.

Here's my first tip. Do a few road racing days first. A modern road car is built to suit as much of a target market as possible. The point of modification is to make the car suit you better, and until you know what the car's lacking you won't know how effective your modifications are for your purposes.

Also, what's your usage of the car? Is it going to be a weekend-only car that only gets used at AutoX/road racing events, with its only street use driving to the venue? Or is it a car you'll drive every day, and used for motorsport once every few weeks? Do you care about the resale value of the car? This will affect what you can and are willing to do.
First tip is noted! I will definately take that into consideration. :thumbsup:

As for the driving part, I live on Base and drive the car only when absolutely needed. I run or ruck to/from work everyday (only like 3 miles there). So the car is only driven when needed. Maybe to pick up things or run errands every now and then. Approx. 15-40mi a week. Resale of the car...I realize everyone will probably say this, but it is my forever car.Have always wanted one, and have no reason or want to ever get rid of it. plans are to buy a cheap gas saver eventually anyway.

I'd personally get a coilover kit rather than buying the springs and dampers separately. At least you know the spring and damper rates are properly matched, and it gives you the ability to height adjust to corner weight the car.
CHECK! Any you suggest? or heard of some in particular you think would be good. For a guy on a lil bit of a budget... not wanting to just buy the best, but I dont want crap either.

I also have heard great things about the Hotchkis sway bar kit. So thats a Go.

I wouldn't bother from a performance perspective. The OEM airbox is actually quite well designed, so using a freer-flowing K&N panel filter will give you better performance than most aftermarket intakes.
I have heard this alot, mainly was just going for the wrinkle black look intake Injen has. But looks like my plan has changed, Thanks again.

The Top Speed looks like a copy of the Buddy Club exhaust, which I've got. It's loud and droney at light throttle application, but if you can bear with it around town it makes a terrific noise at WOT. Most catbacks give the same performance on NA cars, so performance-wise its much of a muchness. Just make sure you don't get a true-dual as those make hardly any more power on peak, but sacrifice a fair amount in the midrange.
Well personally I dont really ever want to go TC/SC. I like the feel of an NA car anyday, always having the power the instant you need it. Future (long Future) plans look good for the BC 4.15L stroker, or the AEBS 4.3L stroker. Again once I become a better driver myself. I personally like the Single exit exhaust, but I will make sure to steer away from true-dual. dont want any less ponies for any reason at all.

This boils down to where you're driving it. Every gearchange reduces acceleration on throttle, and unless you're really expert it can also reduce the stability and rate of your deceleration under brakes. The extra in-gear acceleration needs to offset this time loss. Unless you can max out the highest gear you use you might find yourself going slower.
The Main Road Racing Courses close to my location are;
Sears Point/Infineon(30min)
Thunderhill( <2hrs)
Mazda Raceway Laguna SECA( <3hrs)
From my perspective they seem like pretty fast courses, but of course they are the only three I have ever been on

If this car is street driven you're better off abusing a set of dedicated track tires, and saving another set purely for street use. It means you can go very aggressive on your track tires (which will be noisy, not last very long, and have no grip when they're cold or its wet) and still maintain a set of street tires that are quiet, work in more weather conditions, and get decent mileage out of them.
my plan was to get a special set of wheels/tires for racing and nothing else, and keeping the ones I have for just during the weeks of no races. It actually does not rain here very often, (between San Francisco and Sacramento CA) exept in the rainy season, late Dec-Mar. Other than those few months, its a drought in the summer where it gets in the 100's. The other two seasons usually stay around 50-75F

If you're willing to pull out the interior in the car, do it. Weight reduction is a great "free" mod that benefits all aspects of a car's performance. Of course the car will be uncomfortable on the street with all the trim missing and the sound deadening scraped off, but it will drive a lot better.
And finally, this is happening as soon as the new dd is here. :D

Scathing I cant thank you enough. This was an awesome post and answered everything just as I had hoped. If you wouldnt mind though, do you have any advice for a novice soon to be Road Racer(hopefully)? I really want to dedicate alot of time/labor to this. I have worked and tinkered on many cars since I was 13, but it was always Drag. Im tired of seeing things go in a straight line as fast as possible. and especially when it comes down to which cars breaks loses. NHRA. As you noted earlier, I want to better myself/Driving. And I feel this car is a great one to start with.

Thanks again,
Kyle
 

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As for the driving part, I live on Base and drive the car only when absolutely needed. I run or ruck to/from work everyday (only like 3 miles there). So the car is only driven when needed. Maybe to pick up things or run errands every now and then. Approx. 15-40mi a week. Resale of the car...I realize everyone will probably say this, but it is my forever car.Have always wanted one, and have no reason or want to ever get rid of it.
Gut the interior then. If you're sensible about it you can remove the trim in a way that lets you put it all back afterwards. If you're willing to invest the time, get some dry ice and use it to scrape all the sound deadening off.

Aside from buying dry ice and protective gloves, if you can DIY then this step costs almost nothing.

If there's no issues with you removing the airbags, take them all out (you can't run the OEM airbags aside from the steering wheel one if you put a rollcage in anyway). The OEM seats are pretty heavy, and while comfortable don't really hold you in place.

CHECK! Any you suggest? or heard of some in particular you think would be good. For a guy on a lil bit of a budget... not wanting to just buy the best, but I dont want crap either.
Not sure, since I haven't tried enough coilover kits on the track to be sure. I'm running Tein Flex with 670lb/in springs. I find them a bit too stiff for the street, given Australia's rough roads, but on the track they've still got a bit more roll than I'd like.

That said, quite a few of the pro instructors like a little bit of compliance in the suspension. Softer suspension gives you more grip, but at the expense of chassis response.

I've seen video tutorials from pro drivers that use bodyroll for weight shifting, which in turn provides more grip. For example when you brake, the weight shifts forward and provides more downforce over the tires that help you turn. When you get back on the throttle, the weight shifts rear onto the tires trying to put the power down. At the same time, too much roll means the car is slow to respond to steering inputs and lifting a wheel off the ground means you lose the grip the tire would provide.

Finding the right balance between the two is a very personal preference, so its one of those things you need to experiment with. You need to get out there, find your style of driving, and then modify to suit.

My personal preference for a car is that is neutral off the throttle, and gently understeers under power at the limit. I also like it progressive, and I'm willing to sacrifice a bit of response to get it. This setup makes the car "easy" to drive. I get the car into the corner, then step on it on corner exit. If I break traction because I applied too much throttle, it slowly pushes the nose wide without ploughing.

I can either ride it out if there's enough road on exit to let me run wide, and lifting off just tucks the nose in line without giving me some pants-ruining lift-off oversteer. It means that I can belt out lap after lap and cluster my times within a few tenths of each other up until my tires overheat.

However, I've got a mate who used to do road racing in a few one-make series (old Aussie sedans and Formula Fords. He prefers the car being twitchy, since he has the skills and reactions to balance the car on the throttle and wheel. The extra stiffness means the car does what he wants a bit faster, and he can carry more cornering speed. When I drive with that setup my times are a lot less consistent and not that much quicker, but for him he can keep it consistent enough while being a bit faster than with my preferred setup.

Only hitting the track and finding your preferred style of driving will give you an indication of a good setup for you.

Whatever you get, make sure its adjustable to a certain extent. You don't want it too adjustable, especially as a beginner, since, it just means you've got more possible "wrong" setups. Whenever I see "32 way adjustable" no-name coilovers I roll my eyes. Chances are a newbie will not be able to feel much of a difference between each individual click, making it completely pointless, and those no-name companies don't spend the R&D time required to match their spring and damper rates to the car so the overall setup is less than ideal anyway.


As a primer, I found this video of Sir Jackie Stewart giving Top Gear UK's James May road racing lessons to be quite useful:


The main points I took away from it were:

1. Drive smoothly and progressively.

2. Corner exit is more important than corner entry.

3. Don't feather the throttle. "never press the gas pedal, until you know you will never have to take it off"


If you have a look, those 3 points match my preferred car setup. But how progressive vs how responsive you want it is up to you.
 

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I've been autocrossing for ~6 years and run:

Ti2000 springs
Koni sport shocks
Hotchkis sways
SPL A-arms
SSR Comp-H wheels (~16lbs each)
Quaife LSD
-And whatever sticky tire is on sale. (Dunlop Star Specs are on the car now)

You said your mind was made up regarding the go-fast parts so I won't try to talk you out of it.

I will say that seat-time-you, in a stock Z, will crush no-seat-time-you in a bolt-on Z every time. Heck, seat-time even trumps FI.
 

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Wow, ignore this, this category doesn't get much love anymore.
 
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