Camber and Sway Bar

[Uber Deaf One]

To all the 510 autocrossers/road racers out there, what kind of camber do you guys run? And what size front sway bars are you running?

 

 

I have my 510 setup with 225/900 lb springs, -2.4/-1.5 degrees camber, and a 1" front swaybar and for some reason the front tires start to slide when I push the car a little bit. I also have a LSD which seem to want to push the front tires straight.... I'm not really sure what the issue is? Is the swaybar too big? Too much front camber? Too little?

[datzenmike]

Classic case of too much front sway bar. Everyone goes out and puts a larger sway bar on their car or adds one to the back with little thought to what this actually does to the handling.

 

It's a balancing act ,and the car should have slight understeer. If you drive in a tight circle and increase the speed until the tires break loose, is it the rear ones, (oversteer) the front ones, (understeer) or both evenly? (neutral) Many many things will increase understeer and stiffening the front sway bar is one of them. Many many thing will decrease understeer too. You can decrease the front bar size to soften it or increase the rear bar to stiffen it. Soften the front springs or stiffen the rears. Softer front tires or firmer rear tires. Wider front tires or narrower rears.

[69FJWagon]

whats your toe settings front and rear as well as your castor settings??? whats type of tires play a big part in it all too I noticed thatwith the same suspention set up and just switching the tires made a huge difference as does ride height a simple rear ride height adjustment can effect if you have a oversteer or understeer sitsuation, I also noticed with a street tire you can change the feel with a simple tire pressure adjustment

 

Clayton

[Uber Deaf One]

My guess is it's the sway bar... definitely feels like the front end is too stiff. I'm not too keen on going softer on the front springs, because it is pretty bad, I feel like I'd have to go down to a 175 lb spring or something just to make the car turn how I want it to. The car came with this swaybar and I don't know where to get a smaller one... I have a KA so regular 510 sway bars won't work. No rear bar, and I don't see the need for one.

 

How about camber? Does -2.4 degrees up front sound like too much? I don't think so.... but just asking.

 

I have some crappy cheap offbrand tires right now... came with the car. They actually grip pretty damn well. Running them at 28/30 psi, don't really want to go any lower up front. I don't really want to add more rear rotation to the car right now (stiffer rear springs, rear sway bar or higher pressures in the rear) since it is driven on the street 99% of the time. Just trying to get some more front grip.

 

Toe is +1/16" front for stability (it is a daily driver) and 1/8" rear to counteract the liftoff oversteer 510s get.

 

Caster is about....... 2.5 degrees on the left front, 2.8 or so on the right front. I'll double check the alignment paper tomorrow which is in the glovebox... next time I go in for an alignment (which will be in the next week or 2) I want to see how high I can go on the caster without binding the control arms and stuff.

 

Where can I get a smaller swaybar that will fit a KA 510?

[CCAT Racing]

KA24DE Swap, 280ZX Front Struts, shortened, Coil Over in Front with Camber Plates, Adjustable Caster Arms, Slotted Rear Cross Member, running 15x7 0 offset, 195/50/15 Tires. 225 # Front Springs, matching rear springs.

 

Here are the Dean Sherman specs I come up with doing a search... For Street AND Track???

Front Camber -1.00 Deg

 

Left Front Caster +1.80 Deg

 

 

Right Front Caster +2.30 Deg

 

Total Front Toe +0.08"

 

 

 

 

Rear Camber -0.40

 

Total Rear Toe 0.04"

 

 

 

 

The problem I notice, is at low/middle speeds if you don't commit into a turn, the front end severely under steers, I think it is excessive Neg Camber in the front? Example, in a windy mountain road at say 35MPH, if you let off throttle right before entering turn like if you entered a tad fast, the front loses grip and will slide into oncoming lane. It seems like the front left should dig in on a right turn off throttle, slow to mid speed?

 

 

 

 

 

Please help us out with your experiences with alignment specs/handling on the 510!

 

 

 

 

Are the Dean Sherman Specs good, or does everyone run more Neg Camber? It seems to me -2.5 is TOO much Neg Camber in the front, and -1.5 is a bit too much for the rear, especially since the 510 came with +1.0 Deg POSITIVE Front Camber from the Factory?

 

 

 

 

We need some REAL advise, not just someone saying " YEAH MORE NEG CAMBER IS BETTER!" LOL

 

 

 

 

 

Thanks in advance...:D

[Master-O-Turbonics]

What are you using for shocks? Shocks are a huge part of turn-in....

Is it understeering on turn in, in the center of the turn, or on-power exit?

 

 

 

KA is a heavy beast and so it sounds like its steering like a Z car with the horrid low speed understeer.

 

Also 225# springs sound a bit stiff. I ran 10" 225# springs in my 2500Lb Z and it was stiff(for the street) but would still travel the front end pretty good(better in-corner geometry/camber gain) if I set the Illumina struts on 2/5.

Since I was running an open diff, I ran no rear sway bar to allow more rear suspension compliance and not lift the inner rear tire on a turn.

 

I have worked SOME with a 510, but have pleeenty of experience in setup of real race cars. LOL

 

Do you have bump steer spacers? They allow you to have a better camber curve so you can have less static camber but your dynamic camber gain is better than stock.

[Uber Deaf One]

It understeers more in the center of the turn.. entry and exit feel great.

 

A lot of people recommended 225 lb springs up front including Troy Ermish...

 

I do have bumpsteer spacers.

 

I'm not sure what inserts I have up front.. I want to say KYB GR2s... and I have KYB GR2s in the rear. Cheap but they work well. It really doesn't feel like a shock issue, definitely feels like a sway bar issue. Does anyone know where I can get a smaller swaybar for a KA swapped 510? And what kind of camber do you guys run on your 510s for autocross/track days/road racing? Does -2.4 degrees up front seem like a lot? It doesn't to me...

 

If my front swaybar is too stiff, theoretically I could remove it and the understeer issue should go away right?

[Master-O-Turbonics]

It understeers more in the center of the turn.. entry and exit feel great.

 

A lot of people recommended 225 lb springs up front including Troy Ermish...

 

I'm not sure what inserts I have up front.. I want to say KYB GR2s... and I have KYB GR2s in the rear. Cheap but they work well. It really doesn't feel like a shock issue, definitely feels like a sway bar issue. Does anyone know where I can get a smaller swaybar for a KA swapped 510? And what kind of camber do you guys run on your 510s for autocross/track days/road racing? Does -2.4 degrees up front seem like a lot? It doesn't to me...

 

Have you had the car scaled/corner balanced?

 

Here is what I am thinking...

 

for LOW speed handling, you are really going to need a lower front spring rate. 225# would be good for a high speed course like Road Atlanta, but on the street with tight corners, its going to push like crazy. Just because Troy Ermish recommended a certain spring rate for a certain car, does not mean that particular spring is correct for every Datsun 510 that is driven fast.... You have to consider your frame heights, DYNAMIC camber, and what speeds you are driving.

 

How did you get -2.4 degrees of camber? what angle is your LCA at at ride height? DO YOU HAVE Bump steer spacers?

If you are at max negative camber at ride height, then your camber will move back TOWARD POSITIVE camber as the suspension compresses.

 

What kind of K-member/engine crossmember heights are you running?

 

There is a lot more going on than just your sway bar. There are 510 guys out there running a lot softer springs and bigger sway bars than you, but I think what you have is a geometry and shock absorber problem.

 

With springs that stiff, you are definitely overpowering your shocks by having such a heavy spring rate, which makes me tend to believe that your rear suspension is unloading on lifting the throttle, which pushes down your outside front tire, and overloads the tire causing the car to push/understeer through the corner.

[Uber Deaf One]

Nah the car isn't corner balanced... still dialing everything else in before I get around to stuff like that.

 

I also thought 225 lbs was too stiff but decided to just start there... here's the thing though, at low speeds in a parking lot the car feels great. I took it up highway 9 the other day going through 3rd gear turns and that's where I noticed the mid corner push.

 

I do have bump steer spacers. The front camber is -2.4 degrees according to an alignment machine at Wheel Works? Not sure what you're asking there... and I understand the camber moves positive as the suspension compresses.

 

It has nothing to do with being on or off the throttle... once I get the car to that point where it starts to push, I can turn the wheel back a tad and it will regain grip. Doesn't matter if I'm on the throttle, or off of it. I can lift off and get some more front grip, apply more throttle and lose a little front grip (as the weight transfers back...) and then try turning the wheel more to where it pushes even more.

[Master-O-Turbonics]

Nah the car isn't corner balanced... still dialing everything else in before I get around to stuff like that.

 

I also thought 225 lbs was too stiff but decided to just start there... here's the thing though, at low speeds in a parking lot the car feels great. I took it up highway 9 the other day going through 3rd gear turns and that's where I noticed the mid corner push.

 

I do have bump steer spacers. The front camber is -2.4 degrees according to an alignment machine at Wheel Works? Not sure what you're asking there... and I understand the camber moves positive as the suspension compresses.

 

It has nothing to do with being on or off the throttle... once I get the car to that point where it starts to push, I can turn the wheel back a tad and it will regain grip. Doesn't matter if I'm on the throttle, or off of it. I can lift off and get some more front grip, apply more throttle and lose a little front grip (as the weight transfers back...) and then try turning the wheel more to where it pushes even more.

 

 

 

 

can you check tire temps? That would really help diagnosing the issue. Get inside, middle, and outside of all of the tires.

 

Tokico illumina struts are only rated up to being used with a 250Lb/In spring before they are overpowered... and I am pretty sure that a 225 is acting pretty hard on those KYB's...

 

 

just trying to refresh my memory here....

Isn't the ratio around 3.3:1 for the leverage factor on the rear swing arms on a 510?

 

I have heard of racers using up to 1400Lb/in springs in the rear of a 510(super low ride height, more leverage on springs?)... but that really puts a beating on the chassis/swing arms.....

[Uber Deaf One]

Nope don't have a pyrometer although I should invest in one as I need one for AutoX anyway. Doesn't seem to be a tire temp issue though.

 

I'm almost positive the problem is just my cheap, shitty offbrand tires. There are a few issues with the car I need to deal with first, then I can get a set of nice tires. I'm thinking about going with some RE-11s... thoughts? 205-50-15s. if the problem still occurs, then I'll probably pick up better shocks/inserts as well as go a little bit softer on the front springs, probably 200 lbs.

 

The ratio is about 3.8:1 so my 900 lb springs come out to about 236 lbs which very closely match the 225s up front.

 

These KYB GR2s are off of a heavier car... a Camaro if I remember correctly, so I'm sure they are OK with 225 lb springs. The rear shocks at least... I'm not sure what the front inserts are out of, I do know they're KYB GR2s though.

 

As for the 1" front swaybar, I still feel that's fairly large for a car of this size. Just for shits and giggles I might unhook the swaybar and see how the car feels without it...

[banzai510(hainz)]

How about use rubber bushings and loosen the nut on the swaybay so the sway bar will give a little more before it transfers the weight.

 

 

Most people dont run rear bars.

 

I dont think ur shocks are the proplem But I like the old Konis "D"s adjustable retraction type. But you need a spcial bushing or something if you have T3 coil overs as the tops are different on the Konis shocks.

I dont think they matter if off a Camero as KYB GR2s they just a ENYTRY LEVEL CHEAP shock and the piston size is usaully the same

 

 

I notice that also if you have a GOOD LSD it will push the car front wards. Maybe key is pedal control going into the corners but Im only guessing as I dont race on a track. get some Under 150 rated compoundrated tires

[Uber Deaf One]

Rubber sway bar bushings are already on the way ;) That will definitely help... previous owner installed this swaybar with poly bushings. They're noisy and way too stiff.

 

I have noticed the (freshly rebuilt) LSD tends to push the car a bit in the turns, especially when on the gas. The problem I'm having occurs no matter what I'm doing with the throttle. It definitely feels like something in the front end... either way too stiff, crappy tires, or a combination of both.

[Boaty]

Well, I really don't have any racing experience (track/autocross, etc). But it's been something I have avidly wanted to get into some day.

 

I went on a goose chase for information some time back, I wanted to learn all sorts of stuff and I wanted to learn it quick. I did this without

the ability to actually -do- it, and thus didn't retain everything I wish I had. But the stuff I do remember, are things I've heard from various people

with extensive time, and research into this stuff as they race themselves, or have raced in the past.

 

I have heard a lot of people complain about understeer issues, regardless of throttle position or power - in regards to a front sway bar. And there are

some things that, at least in my case - take awhile to fully understand but once you get it, it's like *ding* how did that NOT make sense before?

 

If you replace a stock 510 bar with an upgraded bar, let's say one step up - it's going to be stiffer. This is very apparent.

But, the bars are the same shape. So obviously since it's spring steel, you take the same length of bar, and increase it's diameter to change spring rate.

 

Now you're using a front-sump sway bar, and thus the bar is now longer than stock. So let's say your 1" front bar is larger than your, let's say 7/8" bar you had previously.

The additional length of the front-sump bar is going to change it's spring rate, the same way that length of a coil spring changes it's rate.

 

The way I understand it, the 1" front sway bar for a front-sump configuration is roughly equivalent to a 7/8" sway bar in a rear-sump configuration.

Similar goes for the way rear sway bars are in a 510. There a few different styles of 510 bar, one that clamps to the crossmember, and clamps to the rear control arms

roughly near the spring cup, there's one that mounts to the crossmember with bushings, and uses endlinks to mount it to the control arms, and there is one

that mounts to the crossmember, but bolts to the control arms where the shock mounts. All the lenghts are different, but IIRC, their effective spring rate are very close to one another.

 

Not sure on the brand names or manufacturers, been awhile since I researched this - but, the 3/4" bar that mounts with end links has almost identical spring rate to the 7/8"

bar that mounts to the lower shock mounts - and it is larger, because the length of bar is longer as well.

 

When I moved up to a 22mm sway bar (7/8"???), I noticed a slight amount of understeer over the stock sway bar. I also ran my LSD with both the stock and upgraded bars.

It's not that drastic of traction loss, but it's definitely noticeable. It was only scary on wet pavement. It was a large improvement over stock, regardless.

 

Now, since you say the understeer is pretty static, it doesn't really care if you're on throttle or off throttle, it just happens mid-corner, I am going to agree that your spring rate is a little high for GR-2s.

They hold, yes and they probably ride alright - sure. But once you get them working hard, those GR-2's are going to struggle to control that much spring. A GR-2, is a KYB OEM replacement strut insert.

Nothing special about them at all. If you have the money put out for coilovers and suspension mods, I am surprised to hear you're running them. Tokico Illumina's are great struts, and I have only

ever heard one person complain about them - and it was because he was too dense to understand the concept of how they work. He cranked them up to 5 and complained that they were

too stiff, go figure! 5/5 is like a ROCK!

 

Without spending too much money, I would replace your inserts with something higher end. As far as coming from a Camaro, well - it's still an OEM shock. Valving may be different - and that alone

may be the cause of your understeer! In an effort to get 'stiffer', you actually got too stiff perhaps?

 

Illumina's aren't cheap but I see a *lot* of them being run at the autocross (Spring/Fall Enduro) over in White City, OR. KYB AGX's are being ran on a lot of 510's out there.

May just be the ticket you need - and, it'll give you some adjust-ability either way. When I move up to coilovers, I will likely be running AGX's on my dime. Haven't heard many complaints about them, yet.

 

If you wanted to go that route, I would leave your current spring rates alone. I think you're in the gray-area for spring rates, as you'll find (probably already have) - a LOT of varying opinions.

I know a few guys that raced on 175# 8" springs and found it ideal for street and track, running Koni inserts. I know a couple guys that have run >300#/inch springs... And to top it all off,

at Shasta 2004 (maybe 2005), a guy was running a bone stock 510 automatic, with only a larger front sway bar and decent tires - and he pulled off 3rd place out of the entire autocross, fully race prepped cars and all!

 

I say buy a set of good adjustable inserts, whether they be Tokico or KYB or Koni's, and dial them in and see what your results are. If you NEED to go to a lighter front spring, drop in some 200#'s and try those.

 

Personally, I like about a 200# spring up front. Rides decent, not too stiff - not too soft, and has a nice sporty feel to it. The 375# springed 510 I rode in, felt almost the same, but started to get bouncy in the corners.

 

FWIW, the best 'feel' and predictability in my 510, is when I run 45PSI up front, and 50PSI in the rear. Much more predictable turning, and that extra pressure in the rear helped balance the car a bit without giving me

any unpredictable oversteer issues. Steering input is more precise, and I can feel the road a lot better, too.

[Uber Deaf One]

My understanding is if the car understeers in a steady state corner where the shocks aren't doing anything, then the problem usually isn't the shocks.

 

It could be the shocks though... I'll get that sorted out later. Right now I need to source a cheap running dual cam KA longblock to throw in this 510 for now.. I can't stand driving a car that burns oil Then I am planning on getting nice tires and then going from there. Rubber sway bar bushings are going on as well. I do want to get some nice adjustable shocks as well, for sure. I think I might drop down to 200 lb springs up front as well.. could only help. It really does seem like a 1" front bar is too big for a car this small.... my dad's '09 Mazdaspeed 3 has a 1" front sway bar and that thing weighs 3200 lbs.

 

45/50 psi seems quite a bit on the high side... is that for driving around or just for autocross? I'm down to 28 psi all around right now for daily driving and canyon runs.

[Uber Deaf One]

Sooo I took the 510 in this morning to check the alignment. I wanted to make sure the rear hadn't moved since I tackwelded the washers. They're still at -1.5 degrees. Awesome. I guess the machine was reading wrong last time I was in Front camber was at -1.9 and -2.8. Got that fixed... running -2.0 degrees up front. I had them up the caster a degree, running at 3.4 degrees now. Went for a fairly spirited drive with my dad up Page Mill Road. The understeer issue? 100% fixed. Simply with a caster change. I know it wasn't the -2.8 degrees of camber because it did it in left and right hand turns. I also have a bent tie rod which I'm sure doesn't help the toe while cornering....

 

I'll upload the videos later tonight :)

[Boaty]

45/50 psi seems quite a bit on the high side... is that for driving around or just for autocross? I'm down to 28 psi all around right now for daily driving and canyon runs.

 

I drive it like that all the time. If I ran 28psi, I would never be able to turn the fucking wheel in a parking lot. And it would chaff the all living shit out of the front tires if ever tried to push it.

 

Anything less than 35, and it feels like I'm riding on bubblegum. Poor input, poor response. When I first bought my old set of tires (T1-R's), they set pressure to 32psi when I drove off.

Taking the first corner, it felt like I had a flat tire. Drove back, they ramped it up to 40 and voila. Whole new car.

 

It all depends on the tire, though. I can run 55psi if I wanted to, but that's way to harsh and the car isn't really heavy enough. Like driving on concrete tires.

In my snow tires if I run over 35 it feels like I'm going to *bounce* off the road. Normal driving around I keep them at 30psi. Feels just about right.

If I intend on driving around in the snow/ice then I drop them down to 25 or so. Think I ran them at 20psi with chains once. Fine in the snow, holy-shit-whoa back on pavement.

 

Lowest I ever ran in a tire was 15psi at the drag strip, but I was getting wheel-slip so ramped back up to 20psi. (Wheel slip as in wheel spinning inside tire. I always mark them with a paint-pen if I go run the strip.)

 

Also, talking about static load turns and shocks not playing a part in it... go slap some shit-struts and disconnect the rear shocks. Then come back and tell us the results... lol.

Dampening also helps maintain load balance through a corner. It's not their primary role (which is dampening) but if you don't have them there, you'll definitely know it with any sudden steering angle changes.

 

As far as alignment goes, the consensus is pretty much all the same for "spirited folk".

As much caster as you can possibly manage,

-1.5 to -2 degrees of camber up front, -1 to -1.5 of camber in the back.

If you want more turn in, toe out 1/16th. If you want stability, toe in 1/16th. For speed, 0 toe. I was told that rear should always be close to zero toe at settled suspension height, if not toe-in for stability (and to counter the toe-out effect under rear suspension load). Don't quote me on that though. Toe-out would give you more rotation, toe-in would once again give you more stability.

[Boaty]

Oh. And get that tie rod fixed. They are cheap. And if you're running around with this spirited driving style, the last thing you want is a busted tie rod because of fatigue.

And then you'll be back on the alignment rack :D

 

FWIW I'd replace all of them at once even if the others are still 'good'. At least if they are old/original tie rod ends. For some reason you fix one thing, the rest will fail soon afterwards. :/

 

 

Who just replaces one worn tire?

Who just adjusts one valve?

Who only replaces one spark plug?

[Uber Deaf One]

Yep new tie rod ends will be here shortly.

 

The car will be on the alignment rack quite a few times over the next couple months getting the alignment dialed in. I paid $100 for a year's worth of alignments... might as well take advantage ;) Already wanting to go up more on the caster. Next time I am going to have them bump up the caster as high as it'll go without binding the control arm bushings. Camber feels pretty good at -2/-1.5, I'll keep an eye on tire wear and maybe go a little more negative up front if the tires look OK.

 

Thanks for the help mang

[Boaty]

After -1.5 degrees camber up front you'll probably start degrading braking performance. It's nothing major, some people will love to exaggerate that point to no end. But it does have merit. On anything driven on the street, I wouldn't go any further than -2 degrees honestly. This will save your tires in the long run as well. Combine that with odd toe settings and it's a real good way to eat up your tires, and you're not going to be able to ever find out just how awesome that alignment is going to change handling characteristics. I'd keep it -1.5 and call it good. On high camber settings you may notice differences in steering input. Mixed feelings here though, some people run massive amounts and don't have any issue turning the wheel - others complain about it being too darty.

 

Just make mild increments and remember too much is just as bad as too little.

 

When I replaced the ball joints, tie rod ends, bushings, and went up to a larger sway bar and refreshed my brakes, I had to learn how to drive my car again!

For me, I need to get a new steering box. Mine is getting worn out and adjustment does no good. The stupid little U-joints for the steering have also started to wear out... turning the steering wheel produces an annoying clunk and I can feel it while driving.

[Master-O-Turbonics]

My understanding is if the car understeers in a steady state corner where the shocks aren't doing anything, then the problem usually isn't the shocks.

 

 

Shock absorbers never stop working.

 

Whether the car is parked in a parking lot, or you are in a "steady state" corner, shocks are always working in some fashion.

[FastDat]

This might have been stated earlier and I missed it. Before you make any changes, liquid paper the outside edge of your front tires, 1 inch on the tread and 1 inch on the sidewall. Run the car and see what rubs off. The goal is to get to the edge of the sidewall. Good information does not have to cost a lot. With 2.4 degrees of neg camber and not knowing your ride height and bump info, the first thing you need to do is ensure the tire can get "FLAT" to the ground. Everything you do to your car is to get and keep the 4 tire contact patches as flat to the ground for the most dynamic situations. If the tire is too hard and the camber is too much, the tire will lose grip before your suspension compresses and the camber changes to make the tire "flat". My guess is 1.25 to 1.5 neg camber will be a better starting point. A tire pyrometer is the next step after you confirm you are getting enough roll. It is a game of "iterations" and dialing in the car. Always go back to making sure you are using the whole tire. Changes that reduce that are going in the wrong direction. Hope that helps.

[Uber Deaf One]

Yep thanks for the post. I took my swaybar off Saturday night and discovered the 2 frame bushings weren't greased. Ever. With the end links disconnected it took a good 50 lbs of force just to twist the sway bar up and down I also replaced the end link poly bushings with regular rubber bushings to soften the front end up even more. Car feels awesome now!

 

Right now the whole tire is definitely being used, could actually use MORE camber. Gonna wait until I get nicer tires though.