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Simian Rex
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Discussion Starter #1
There has been a lot of talk about lowering methods in the last few days. I know this, because I've been doing most of the talking. Several people have PM'ed me asking for spring advice, clarification on why I like or dislike something, and other things that have been addressed ad infinitum before. To those people: You know what I think because I've said it before. It's up to you now do something with the information I've shared. I reserve the right to point and snicker, though, if you do something that doesn't work when I've told you that it wouldn't work. You, conversely, are allowed to point and snicker at me if you find something that does work, when I raised Holy Hell telling you that it wouldn't. I'm just trying to be helpful, though, so I cannot be held legally responsible if you choose to do something that puts you or your car or it's passengers at risk. ALWAYS triple-check my advice with your own research.

The Subject De Jour, is alignment. There are three basic facts on this subject, and in no particular order of magnitude:
  • The factory alignment settings for the front suck.
  • The rear alignment is all but 100% non-adjustable.
  • If you lower your car, you need to have your alignment checked and probably adjusted.
Here's what I know, and what I think about what I know. I apologize if the fact is mixed too heavily with opinion, but I'd love to help you by making myself clearer if you don't understand something.

First of all, camber kits are a bad idea on our cars, according to Mike Kojima. I don't know why Mike hate's 'em, but he does. That's not the point, though. The reason you don't need a camber kit is because the B15 doesn't move that much when you lower it by only a couple of inches. I don't really know why our camber doesn't change that much, but it doesn't. Anybody who "needed" a camber kit, especially a stupid crash bolt, either doesn't know how to read an alignment machine or was lied to by somebody who does.

Even if you did lose a little bit of camber (which is usually less than 1º), it can only be a good thing. B15s are entirely too hard on the outside shoulder of the front tires. You can fix this two ways; dial the toe outward, or dial the camber negative.

According to the '00 FSM, our toe should be between -1mm and -3mm ("-" means inward, I'll let you do the metric conversion to figure out what that is in inches). This is what primarily contributes to the outer shoulder wear on a B15, especially with the stock suspension. It's a DIY job to dial this to 0 (in or mm, zero is zero ;)), but you have to know what you're looking for. There used to be a HowTo on this, but our Fearless Leader decided to remove it. I'll talk with him about this. ;) Anyway, setting the toe to 0 should help a LOT for even wear, especially you spirited types. The down side is that the steering becomes less "forgiving," meaning that it reacts quicker and more agressively to inputs. Some people call this "darty" behavior. I call +¼" darty, but 0 is just spirited. When you drop, there's a very good chance that your toe will exceed 0 (become positive), which is why it's critical that you check this. Your new stance, left unchecked, could likely get you killed the first time you try to make an emergency maneuver.

According to the '00 FSM, our camber is allowed to be anywhere between +0.75º and -1.10º. Even this is too conservative. If you autocross, -1.5º should be considered your starting point to align for even tire warming and wear. Again, I sincerely doubt that you'll be able to exceed the negative maximums as mentioned by the FSM with a simple drop spring, and even if you do, you're only approaching the ideal handling settings. On a street car, 1.5º is nothing to be afraid of, though 2º may be a little to whacky for a lot of people, so do have it checked. If you're under 1.5º, though, don't bother trying to get it fixed.

This particular advice becomes especially relevant once you realize that the camber on a B15 is not designed to be adjusted (hence the "need" for crash bolts). If, for some reason, you do need to adjust your, do not use crash bolts. Talk to the alignment techs before you let any monkeys lay a wrench on your car, and make sure that the man (or woman) responsible for your car is familliar with slotting strut mounting holes. There are two holes that hold the strut body to the spindle, one on top and one on bottom. Bolts are driven through the spindle and through these holes during final assembly. By using a tool to elongate the bottom hole, you can adjust the camber on just about any car by intentionally making it "sloppy." This is the method recommended by most members of the SE-R community, and is supposedly orders of magnitude safer and better than crash bolts. Again, I don't know why, I'm just parrotting info for you people that haven't done the research on your own.

I'm going to leave this open for discussion, but I want it sticky for a couple of days.
 

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WARNING about alignment.

If you lower your car do you need alignment? - Yep.

It's a good thing to go to a racing shop so they can adjust it exactly to a spec. Do not go a a regular car shop, because most hags will just throw the car onto a racket and if it falls anywhere within a very wide ranged factory specs they wont touch a thing. But you will need to adjust it to spec. Adjustment is done while the mechanic balances the car to the spec with the drivers weight in the seat.

Also if you lower your car with aftermarket springs it would be a good idea to get new shocks because aftermarket springs will quickly annihilate the factory shocks causing a sentra to become a low rider.

Hope this helps a bit too.

Major thanks to sentra network.
 

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Re: WARNING about alignment.

StreetRacer said:

Also if you lower your car with aftermarket springs it would be a good idea to get new shocks because aftermarket springs will quickly annihilate the factory shocks causing a sentra to become a low rider.
There are currently no aftermarket shocks / struts available for our b15's.
 

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I autocross ALOT and can attest that even with the 1.0 of negative camber that I have and 37PSI in Falken Azenis, the car just loves to ride the outside edge of the tire. Now, would increasing the camber to -1.5 affect tire wear (dramatically) on the street? What would be the "limit" before you roast the insides of your tires like any Civic on the street? I guess that your recommendation would also be a minimum of "0" toe or maybe +1/16" (pointing out)?

Although I use different tires on the track than I do on the street, I don't want to have to adjust the alignment 3-4 times a month depending on events.
 

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Simian Rex
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3,213 Posts
Discussion Starter #5
Alignment settings at that level are a matter of taste. The pyramid-shaped Civics that you see are often approaching or exceeding -3 to -4 degrees; B15s have a looooong way to go before we start "roasting" the insides. :)

The more agressive you are as a driver, the more you can put up with out of your suspension, and the better your tires can potentially wear. It's all about tuning, and the driver is just as big of a factor as ambient temperature or condition of the bushings; it all comes into play.

A little bit of toe-out would definitely be good for autocrossing, and the good news is that you can adjust that setting in a matter of minutes. You don't want to go over 1/4", but I really don't think there's anything wrong with 1/8" as long as you keep it 'tween the cones. You don't want to get out on the highway at 1/4", though. ;)
 

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I vote for speaking to the fearless leader to get the FAQ on the alignment back up!
 

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sonnypippo
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6,461 Posts
dren- when we go for an alignment at a shop, can we tell them what to set the toe and camber at? or are they required by law to set them within the FSM specs?
 

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Now I have two boys!
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I think he'll tell you to do it yourself, but I could be wrong ;)

I would go and have them check it before setting it (most places will do that before so you know how many wheels they have to do WHAT to, thus what you are authorizing them to charge you when you pick it up). If it's within Spec AFAYK then tell them to leave it be, you don't wanna pay for it. Otherwise you might be able to get them to tweak it, although I would try it myself under the right conditions.
 

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sonnypippo
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tredragon said:
I think he'll tell you to do it yourself, but I could be wrong ;)

I would go and have them check it before setting it (most places will do that before so you know how many wheels they have to do WHAT to, thus what you are authorizing them to charge you when you pick it up). If it's within Spec AFAYK then tell them to leave it be, you don't wanna pay for it. Otherwise you might be able to get them to tweak it, although I would try it myself under the right conditions.
i would do it myself too if it's not that difficult to do it right. from dren's post, it seems 0 toe and < -1* camber is ideal for street driving (which are outside of FSM specs).
 

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Now I have two boys!
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I'd like to have just a tiny bit of toe, maybe even only 1/16" if possible, but 0 is fine. A little neg. camber wouldn't hurt our underdriving cars either!
 

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Now I have two boys!
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Yes of course! Outward just a tad bit (see Dren's first post)
 

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creating HAVOK
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well this little FAQ really helped a lot....you see i was wondering why the front tires wore out more to the outside versus the rears.... I was going to get an alignment done because of that but not i know why so i still dont need I hope. but I have another question.....my steering wheel rattles(not to an exreme but noticably enough where i know it was not doing that when i first got my SE) and it has the tendency to make the car drive towards the right...now because of this and the fact that i saw how the tires wear i thought that i needed an alingment, but now i know i dont, but the steering wheel thing i do want to get fixed what do you guys suggest?
 

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NG Autoworks
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Just a little note for StreetRacer:

After installing my Eibach sportline springs, I had our shop check my alignment, it was RIGHT ON, and WELL withing factory specs. I didn't believe it, so I took it to a well known suspension shop. They also concluded it was RIGHT ON.

Do what you will with my response.
 

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I was wondering about two things about the alignment:

1. Why are the FSM camber settings are in the range of two degrees? I mean from +0.7 some to -1. some? that's pretty wide range and if the left wheel is a positive camber and right one at the negative - that will make for a funny handling car?

2. When talking about the autocross tire wear noone mentions the caster. But at the high steering angles the caster becomes quite important, the more caster - the better for the outside of the tire. Our cars have, if I am not mistaken, zero caster which will chew up the outside tire shoulder in the hurry if you like spirited turns.


To Cdren:

thanks for the info on the toe settings. I didn't know the car is toed in from the factory.
 

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Simian Rex
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3,213 Posts
Discussion Starter #18
1. IIRC, the FSM also specifies a maximum deviation; one side should not be more than .25* or something like that from the other. Don't quote me, but I thought I saw that.

2. Maximum Forward Caster is fun. :)

I help where I can.
 

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NiceGuy said:
Just a little note for StreetRacer:

After installing my Eibach sportline springs, I had our shop check my alignment, it was RIGHT ON, and WELL withing factory specs. I didn't believe it, so I took it to a well known suspension shop. They also concluded it was RIGHT ON.

Do what you will with my response.
My experience with a mirage was totally different. :(
I guess its good to find a place where people know what they are doing.
 
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