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240Stilo
02-21-2004, 04:37 AM
For those that have dipped into some literature in the motorsports genre let me know if there has been any mention to how a car reacts to having a wider track in the rear versus wider track in the front vs both front and back with equal tracks. I just thought about it because go karts have wider tracks in the rear and handle well.

Replicant_S14
02-21-2004, 09:40 AM
For those that have dipped into some literature in the motorsports genre let me know if there has been any mention to how a car reacts to having a wider track in the rear versus wider track in the front vs both front and back with equal tracks. I just thought about it because go karts have wider tracks in the rear and handle well.

Fancy Karts have adjustable track.

The general theory is:
A wider front track reduces the amount of lateral load transfer across
the front axle, improving the front tires' cornering capability and reducing
understeer. A wider rear track reduces the amount of lateral load transfer across the rear axle, improving the rear tires' cornering capability and increasing understeer.

I have zero experience in it's practical application, so how it plays out on our cars specifically is a mystery.

carfreak
02-21-2004, 11:42 AM
Hi, I'm new to the site.
In the book "How To Make Your Car Handle," by Fred Puhn, it says that to get the top handling out of any rwd car the rear track width must be wider. This is the reason that most exotic cars are built with wider rear tires and wider rear tracks than the fronts. Most race cars are the same way, especially open wheels. In their case, with the amount of power that they produce, they would have absoluteltly no warning at the limit of lateral grip meaning that you almost never would be able to keep the rear of the car tucked in behind the front where it should be.

hondaguy
02-21-2004, 01:40 PM
i would say the front example 215/50/15 for the front and 205/55/15 for the rear less understeer but thats just me but what carfreak says does make sense so i dunno
good luck

nightwalker
02-21-2004, 09:56 PM
Personally, I've tried various setups and the wider rear track works better on my 240. Most people will tell you to use an even wheel/tire setup for a more nuetral handling car (240sx). But there is so much more to that than just the wheels and tires. You have to take into account all your suspension mods and settings.

I would stay away from a wider front than rear track. This is not a balanced setup and will leave you with less control. It's reserved for the front wheel drive guys.

Spend some time learning about suspension and tires, and play with the different arangements. (borrow rims and tires from friends if you have to) It will take a while, but you'll eventually narrow it down.

hondaguy
02-22-2004, 02:00 AM
I would stay away from a wider front than rear track. This is not a balanced setup and will leave you with less control. It's reserved for the front wheel drive guys.


cuz im a hondaguy :doh:

adey
02-22-2004, 04:43 AM
wider rear track works better on my 240.
<snip>
there is so much more to that than just the wheels and tires. You have to take into account all your suspension mods and settings.
May I ask why it is that a wider rear track works better on your 240 and what kind of driving it works better for? ... I think it's important to list since we don't all do the same type of (track) driving!

I'll whole heartedly agree with your latter statement about taking into account the rest of your suspension and its geometry -- There really isn't any way for us to adjust track other than offset of our wheels -- which, unless you're running 16*9 -10 wheels, won't make much of a noticable difference to most of us.

The only way I know of to adjust rear track is to widen the subframe and axles if need be. Other than that, you'll have to rely on finding lower and lower offset wheels.

In the front, an adjustable lower control arm used with maxed out camber plates (to max +camber) will get you a limited amount of extra track, but probably not more than 6 or 7 centimeters. Using offset of wheels to adjust front track has a few mentionable weak points... of which I'm not familiar to explain, but are definitely present. Some "terms" to think about are scrub radius, ackerman steering and... umm... yeah. driftingpanda could chime in on this if he ever reads the thread. :)

nightwalker
02-22-2004, 07:20 AM
I spend some time on a particular road, and have noticed that my car is more stable and predictable with my lower offset wheels in the back, and not so low offset wheels in the front. This is with same size tires. The road is pretty off camber in some parts, and has really nice low speed and high speed turns. With same offset wheels all around, my car is pretty neutral, by switching to low offset in front, the car has a hint of oversteer, which I like. I'm not doing too much steering, and the car seems to turn itself. What I've been taught is the less you have to steer into a corner, the faster you will be. Unless you're scrubbing off in the rear, which I don't seem to be doing.

sykikchimp
02-23-2004, 10:42 AM
I think I'm going to try a bit wider rear tire with my next set. I usually have to tune out quite a bit of over-steer when running with same size tires all around.

I have 215/45's all around with the rear and front having a bit more track than stock, and the rear with a touch more than the front. Car still oversteers slightly. I end up having to soften my rear dampers too much to control the oversteer, and I'm not properly damping my springs on track.

I think I would rather run a 215 f and 225 rear, to balance the car a bit better allowing me to up the damping all around, and better tune handling with the sway bars.

I think the wider tires you can get the better. On throttle grip on corner exit is what really makes for good speed down the straights. The faster you are at the end of the straight, the faster your lap times. I need to play with this more, but the more rear tire grip I can get without making the car push, the better.

Something you have to be carefull about with this kind of tuning is the possibility of causing all sorts of odd issues with suspension geometry that could make living with the car daily fairly difficult. The kind of suspension alignment, and settings required to get the most from the car, and tires is often far to aggresive for a daily driver.

Var
02-23-2004, 02:16 PM
There really isn't any way for us to adjust track other than offset of our wheels


what about hubcentric spacers? or am i misunderstanding this whole thread?

240Stilo
02-23-2004, 02:26 PM
what about hubcentric spacers? or am i misunderstanding this whole thread?

Yeah I got 235/45 all around and was thinking of just getting some 1 inch spacers for the rear. For one to make it flush, and because I saw that many other RWD cars have a wider rear track.

Replicant_S14
02-23-2004, 03:03 PM
For one to make it flush, and because I saw that many other RWD cars have a wider rear track.


*sigh*
:fruit:

sykikchimp
02-23-2004, 03:16 PM
Spacers would serve the same purpose.

TRUENOCOUPE
02-23-2004, 03:31 PM
Im too busy at work to write a whole damn essay is regards to wheels and suspension.

Wheels plays one thing on the track but doesn't stop their. There is a shietload of things that plays into 'car handling'.

These things comes in play when you start stepping your toes into track days etc... It'll comes together.

As for Spacer... IMO they are not safe.

Goodluck and I suggest you spend your money on going to track days and find out yourself. Everything doesn't apply to all drivers. They all play differently. Stop wasting money and get your butt out their and find out yourself.

Bbandit
02-23-2004, 04:20 PM
my setup:
16x7 + 205/55 fronts
16x8 + 225/50 rears

this setup suits my driving style perfectly.
i tried even tires before (215/45 R17 fronts and rears).
it didnt suit me quite well.. too much oversteer in autocrosses...

with the setup i have now.. my corner speed is slightly faster and the car felt more balanced and predictable.
but thats just me and my driving style..
i rarely understeers with my current setup... the only way im going to understeer is when i accidentaly lock the front brakes entering a corner.. ::blush::

240Stilo
02-23-2004, 05:14 PM
*sigh*
:fruit:

Haha...Sorry but I gotta admit they do look good.



As for Spacer... IMO they are not safe.


Eibach seems to disagree since they are now starting to make hubcentric spacers as well.

TRUENOCOUPE
02-23-2004, 05:43 PM
Eibach seems to disagree since they are now starting to make hubcentric spacers as well.

Eibach is not the greatest suspension tuner in the world. Half of there shiet is POS.

It doesn't take a special brain to figure out of why spacers are not that safe.

You may be able to run with them for a long time and call it 'lucky' but it you are looking into road racing, Then don't be a cheapo and adding spacers on short studs. Buy the right wheel for the car.

Var
02-23-2004, 05:48 PM
Eibach is not the greatest suspension tuner in the world. Half of there shiet is POS.

It doesn't take a special brain to figure out of why spacers are not that safe.

You may be able to run with them for a long time and call it 'lucky' but it you are looking into road racing, Then don't be a cheapo and adding spacers on short studs. Buy the right wheel for the car.


what about the hubcentric spacers that H&R sells. they bolt on to your hub, then they have their own studs coming out of the spacer. i know a lot of ppl who use it on the track with no problems.

TRUENOCOUPE
02-23-2004, 06:18 PM
what about the hubcentric spacers that H&R sells. they bolt on to your hub, then they have their own studs coming out of the spacer. i know a lot of ppl who use it on the track with no problems.

Those would work also. But IMO. They are not safe.

You are putting two stress in one.

Anything that is not direct with the hub and strut housing is never safe. The vibration of the strut housing to the wheels can affect lots of things.

Lets just call it 'lucky' for now. I would never suggest spacers.

Bbandit
02-23-2004, 09:43 PM
^^^ i agree.. vibration will create metal fatigue (either long term or short term)... and trust me.. you dont want any metal parts snapping down there

adey
02-24-2004, 01:03 AM
I think the "danger" of running bolt-on spacers is exaggerated. In my 2 (admittedly short) years taking part in track days and drift events, I've never heard of a spacer failing or causing any type of failure. Furthermore they've been in use on D1 cars for at least a couple of years, and they don't seem to suffer any problems from spacers, either.

I don't deny there's added risk in running them, I just don't think that the risks associated with running bolt-on spacers is necessarily as high as people say.

My main concern when running spacers is the considerable unsprung and rotating mass that they add.

DS 240R
02-24-2004, 10:29 AM
I think the "danger" of running bolt-on spacers is exaggerated. In my 2 (admittedly short) years taking part in track days and drift events, I've never heard of a spacer failing or causing any type of failure. Furthermore they've been in use on D1 cars for at least a couple of years, and they don't seem to suffer any problems from spacers, either.

We've been using 7mm spacers with NISMO 60mm wheel studs for two seasons of racing now without problems. Others have raced more than that long without trouble. I would definitely say spacers are safe. I don't have any experience with bolt-on spacers, but I wouldn't worry about using them in a racing environment.

As for ideal, spacers are far from that. Always better to get the wheel that fits, but that isn't always possible or financially the best way to go. With 1" spacers, you'll probably have increased wear on the wheel bearings and ball joints, but I wouldn't say they are unsafe. I've never heard of a spacer related failure on any car and I've been racing/autoxing/hotlapping for a decade.

My main concern when running spacers is the considerable unsprung and rotating mass that they add.

The 7mm spacers I have are just aluminum and weight just a few ounces. The bolt-on ones would be more weight, but can more than be offset by selecting a lighter wheel or brake package.

nrcooled
02-24-2004, 11:18 AM
From my limited experience I would say the setup that I have currently is the best that I have felt in a s13.

I am running 16x8 rear and 16x7 front with 225/45/16 and 205/50/16 respectively. The car has a much more neutral feel and the sudden oversteer issue is all but gone. Oversteer can be throttle induced but is very controllable and understeer is eliminated as long as I keep my tire pressure set correctly

38 psi front
42 psi rear

At these settings the car just feels "tossable" and very stable

Var
02-24-2004, 11:47 AM
when you post about stuff, let us know your spring rates and other footworks. maybe you can help others (including me) set up their cars better. also you guys with adjustable ride height, what do you set it at front vs rear?

nrcooled
02-24-2004, 01:28 PM
I am running HKS kg/mm springs w/ AGX shocks set to full stiff front and rear to compensate for the higher spring rates

TRUENOCOUPE
02-24-2004, 01:29 PM
Once again...

One person is getting an idea how to set the car in his own driving ability which is the wrong way to do a R&D on your own race/street/auto X/ car.

If you really need to do an R&D get your car out to the track etc... Everything will fall in hands and start noticing things of whats needs to be done.

Moto P over in Club4ag has a various of track times, very knowledgeable on the AE86. I took his suggestion but at the end of the day it was not my ideal of setting up my car. The driving ability wasnt up to speed at the time.

Im not saying he is wrong and you shouldn't do what he says but finding out things on your own is better at the end of the days cause you know what you exactly need for your car and how you want to set it up.

Goodluck.

98sr20ve
02-24-2004, 04:02 PM
Lets just call it 'lucky' for now. I would never suggest spacers.

I know lots of people that use spacers on track cars . They all have studs that pass thru the spacer. The only important thing is that the longer studs don't fail. I do not like the look of the H+R spacers that bolt to the hub and then have bolts attached to the spacer for the wheel. But the ones that are just holes with the extra long bolts should not be any issue. H+R sells both kinds by the way.

TRUENOCOUPE
02-24-2004, 04:10 PM
I know lots of people that use spacers on track cars . They all have studs that pass thru the spacer. The only important thing is that the longer studs don't fail. I do not like the look of the H+R spacers that bolt to the hub and then have bolts attached to the spacer for the wheel. But the ones that are just holes with the extra long bolts should not be any issue. H+R sells both kinds by the way.

I was more settled in with the Hub Centric which is OK but having longer bolts its safer?

I think your logic is going backwards.

Var
02-24-2004, 04:33 PM
ya werd. the ones with their own bolts are more expensive and H&R says they are safe for track use

nrcooled
02-24-2004, 06:32 PM
Once again...

One person is getting an idea how to set the car in his own driving ability which is the wrong way to do a R&D on your own race/street/auto X/ car.

If you really need to do an R&D get your car out to the track etc... Everything will fall in hands and start noticing things of whats needs to be done.

Moto P over in Club4ag has a various of track times, very knowledgeable on the AE86. I took his suggestion but at the end of the day it was not my ideal of setting up my car. The driving ability wasnt up to speed at the time.

Im not saying he is wrong and you shouldn't do what he says but finding out things on your own is better at the end of the days cause you know what you exactly need for your car and how you want to set it up.

Goodluck.

I understand your point but everyone needs a starting point. If he doesn't know where to start he will never get anything accomplished. We both have the same chassis so it is a good way to get info.

TRUENOCOUPE is completely correct track events are the only way to get a feel for your setup. You may absolutely hate my setup but at least you know what you don't like as opposed to knowing nothing

MovinUp-1
02-25-2004, 08:47 PM
What truenocoupe is saying is that his starting point should be at the track, not the parts store. The only way to know what to improve is to first find out what is weakest by DRIVING the car. Seat time will lower your lap times more than any modification will when you first start out.

adey
02-26-2004, 02:00 AM
We've been using 7mm spacers with NISMO 60mm wheel studs for two seasons of racing now without problems. Others have raced more than that long without trouble. I would definitely say spacers are safe. I don't have any experience with bolt-on spacers, but I wouldn't worry about using them in a racing environment.It's good to hear that there're people out there with empirical evidence showing the safety (or rather "not unsafeness") of running spacers! Your input is much appreciated. :)

The 7mm spacers I have are just aluminum and weight just a few ounces. The bolt-on ones would be more weight, but can more than be offset by selecting a lighter wheel or brake package. As much as I'd like to say this is great news, I don't have the cash to make up for this weight any way... at all. :) Except maybe by only eating every other day for 2 months. j/k. Good info!

I'm curious though - do you race competitively, and when (pre)teching, have any techs complained or pointed out your spacers?
Cheers!

240Stilo
02-26-2004, 02:39 AM
Wow...this really turned into a "are spacers safe" thread. Friggin hi-jackers. :rant2:

On a side note...it's good to see people have had no problems with spacers on the track.

DS 240R
02-26-2004, 10:53 AM
I'm curious though - do you race competitively, and when (pre)teching, have any techs complained or pointed out your spacers?

Yes, I do race competitively and no, no one has ever complained about my spacers.

DS 240R
02-26-2004, 10:55 AM
Wow...this really turned into a "are spacers safe" thread. Friggin hi-jackers. :rant2:

On a side note...it's good to see people have had no problems with spacers on the track.

Well, there's not much action in the Motorsports forum. Gotta take any opportunity we get. :)

Replicant_S14
02-26-2004, 03:27 PM
Yes, I do race competitively and no, no one has ever complained about my spacers.

lol, how come some people who track their cars assume everyone else only drives theirs to the mall and back? I mean crap, from the looks of it I'd say half the folks here use their car in some sort of motorsport.

MovinUp-1
02-26-2004, 10:16 PM
To some of us there is a difference between the casual enthusiast who might make an autocross every now and then and those of us that plan our lives around the events calendar for the year. Vacation with the family can only happen in this week in june because I don't have a race those two weekends. You understand what I'm saying. While there may not be a lot of talk in the motorsports section here, it's a lot better than some of the other sites. 240sx forums is full of "drift kings".

AceInHole
02-26-2004, 11:15 PM
my .02: i daily drive my car, but autocross comes first, and i run wheel spacers so my tires clear my shocks.

memphiss13
02-27-2004, 07:37 AM
where are you guys buying your spacers and what brand?

DS 240R
02-27-2004, 10:21 AM
where are you guys buying your spacers and what brand?

My spacers are generic 4x100 for my NX2000. I believe I got them at Pep Boys. They are supposed to be 1/4", but are closer to 7mm. They were $10, which fit the racing budget.

DS 240R
02-27-2004, 10:31 AM
...then and those of us that plan our lives around the events calendar for the year. Vacation with the family can only happen in this week in june because I don't have a race those two weekends. You understand what I'm saying.

Exactly. This year it is May for me. :) When you are really crazy about racing (or maybe just plain crazy) you get a tow vehicle like this:

glc
03-22-2004, 11:21 PM
I just thought about it because go karts have wider tracks in the rear and handle well.
Never compare karts to cars as they have nothing in common. Karts dont have suspension.

btw my kart handles better than all your cars combined :fawk:

240Stilo
03-23-2004, 12:12 AM
Cars have four wheels....so do karts. Take that for nothing in common. The lack of suspension might be comparable to a very stiff suspension.

ryan hagen
03-23-2004, 12:36 AM
I was more settled in with the Hub Centric which is OK but having longer bolts its safer?

I think your logic is going backwards.


think, if u run 7mm spacers how much thread will be left for the lug nut, what is the safe turn number? if i remember right alot of tracks require that the lug nut make so many turns befor its tight? but if u run stock studs with a spacer u risk poping lug nuts off if your spacer is thicker than i think 5mm??

Salty_X
03-23-2004, 01:31 AM
I've found this website (http://rogerkrausracing.com/overundr.html) to be very useful. In it you'll notice that they make mention of widening track (both front and rear) to create a more oversteer-prone suspension setup.

One way for us S13 guys to widen our front track is to install S14 LCAs, which gives about 10mm more per side.

ryan hagen
03-23-2004, 01:38 AM
lol damn, i just was about to toss soem s14 fornt lca's, i took the good ball joint out of one to keep as a back up. hmm, maybe i ll have to look into that after i get my new rims and wide fenders on....

oh i ran 225-40-17 on 17*7 last summer, and got rid of 2 of the tires, and had big brakes on the front so i ran the 17's on the fornt and se wheel on the back with cheap 195 wide tires, all it was good for was donuts and burn outs, cause when i tried to slide corners it would spin too easy and the fornt gripped to much, it always resulted in a donut cause of too poor of traction, and in general it handled like shit.but i got rid of the rims to get some wider lower offset ones.

DS 240R
03-23-2004, 10:57 AM
think, if u run 7mm spacers how much thread will be left for the lug nut, what is the safe turn number? if i remember right alot of tracks require that the lug nut make so many turns befor its tight? but if u run stock studs with a spacer u risk poping lug nuts off if your spacer is thicker than i think 5mm??

In my original post I said I was running the 60mm Nismo studs, so there is plenty of thread left. Probably too much- next time I'll get the 50mm studs.

knghtryde
03-23-2004, 12:52 PM
I'm happy with my 225 45 17 fronts and my 245 45 17 rears. I have plenty of traction, this with my KYB AGX's, sport line springs, strut tower braces, tension rods, Tien tie rods with spacers, ST sway bars, and my power brace.

West
03-23-2004, 02:25 PM
Got any pics of your tire/wheel setup on your car? Im about to get 225/45/17 front and 245/40 or 45/17 rear. Thanks!

knghtryde
03-23-2004, 03:18 PM
Naw, but once my brother gets back from Mexico with my DigiCam I can take some for you. It looks really clean and it's smooth. I'm going to run 235 45 17 fronts and 245 45 17 rears next time around since I found that they fit perfectly fine.

glc
03-23-2004, 04:59 PM
Cars have four wheels....so do karts. Take that for nothing in common. The lack of suspension might be comparable to a very stiff suspension.
The chair that Im sitting in has 6 wheels, so did the '76 Tyrell... one rolls back and forth as I get up and down, the other won a grand prix.

I dont know much about how suspension works on cars, but I do know a bit about how karts turn. I drove a single seater once (obviously race prepped, w/ much stiffer suspension than your roadcars would ever rock), it was very different from a kart.

Karts must lift the inside rear to turn, the reason the rear track is typically so much wider (it gets very close in rain setup) is because the kart relies on weight jacking to turn. If the front gets too wide it will cause to much weight jacking and the IR will lift too much and start to oscilate and cause the kart to 'hop'.

Xren17
03-24-2004, 01:59 PM
Just to let everyone know, you can get nismo studs from http://www.performancenissanparts.com/catalog/product_info.php?products_id=161
for $54 and they're located in Socal. I'm picking up some later today.