Lowering Springs Questions

[Pablitomarrero]

Originally Posted by ayau

The OEM crash bolts are recommended by the Subaru/Toyota service manual to adjust camber front camber.

The reason why they're called "crash bolts" is because they're used to fix camber alignment when you get into an accident.

If your rear camber is way out of factory spec, then the service manual recommends you adjust the rear subframe bolts and/or replace the rear lower control arm.

114 ft-lbs is a lot considering there are 2 bolts per side, and these are massive 19mm bolts. I haven't read anyone's bolts really slipping yet. When torqued to the proper specs, the friction/clamping of the nut is what keeps the bolt from slipping. The shaft of the bolt doesn't take any of burden. Same concept applies to lug nuts/wheel studs.

Oh, crash bolt, that makes sense. Thanks for the huge help!

[ayau]

Originally Posted by barabia

Ok So Im pretty much in the same boat here. Im lowering my car (Eibach sportlines) as well and have had the exact same questions. It's becoming clearer now thanks to you guy but now I have one more question: what about the rear? I ask because I DO intented on doing HPDEs and dont want to ruin the Michelin Pilot Super Sports I just had put on (well I might ruin them on the track but I want to run the right camber anyway). Where do I get rear camber bolts and what angle should I be running?

A couple of things...

An out aligned toe will chew up your tires just as much, possibly more. Imagine taking a tire, face it 45 degrees, and try to drag it straight. This is an exaggerated example but you get the idea.

I believe the Michelin PSS are non-directional. You can swap tires left to right and vice versa if you're worried about camber wear.

Don't lower your car too much (eg., 1'' or less), and you won't get that much rear negative camber. If you do lower it a lot (eg., more than 1''), there are rear camber adjustment options. Lowering it too much may change your suspension geometry too much and actually hurt your performance, but that's an entirely different topic .

[Chase86]

Originally Posted by garfull

I just installed the swifts and did the alignment. I didn't install any crash bolts in the front because my wheels would end up hitting the shock. My numbers ended up like this.

Front R/L camber
-.6/-.5

Rear R/L camber
-2.6/-2.7

I need more front camber but I'll live with it since I don't want to swap out the wheels. Perhaps I'll put in my crash bolts and a 3mm spacer and hope I clear. The rear I need to get a LCA.

What size wheels do you have? How much was the drop?

Won't larger wheels cause there to be a greater difference in camber then smaller/stock wheels?

[Philly758]

I'm pretty new to suspension mods, so this is all good info. I have some RCE springs on the way with OEM crash bolts and have some related questions.
@ayau
You mentioned above that you were able to get -1.5* and -1.7* camber in the front... Is this with the camber adjustment slammed, or did you have it aligned to max camber, was this your final numbers? In other words, I like to do all of my own work, when I install springs with crash bolts and slam it into the most negative adjustment, is that roughly what I will get? I figure that variance wouldnt be far off from what an average alignment shop could do. I'd just be at the mercy of the factory tolerances.

You also mentioned getting the toe dialed in since you are getting an alignment anyways. This doesn't change with the drop, correct? I assume this is just a recomendation.

edit: Thanks!

[ayau]

Originally Posted by Philly758

I'm pretty new to suspension mods, so this is all good info. I have some RCE springs on the way with OEM crash bolts and have some related questions.
@ayau
You mentioned above that you were able to get -1.5* and -1.7* camber in the front... Is this with the camber adjustment slammed, or did you have it aligned to max camber, was this your final numbers? In other words, I like to do all of my own work, when I install springs with crash bolts and slam it into the most negative adjustment, is that roughly what I will get? I figure that variance wouldnt be far off from what an average alignment shop could do. I'd just be at the mercy of the factory tolerances.

You also mentioned getting the toe dialed in since you are getting an alignment anyways. This doesn't change with the drop, correct? I assume this is just a recomendation.

edit: Thanks!

Basically my mechanic just "slammed" as much negative camber as possible with the crash bolts. There wasn't really any real camber alignment done. A factory car only allows you to adjust the toe. Most people seem to be able to get camber on both sides pretty evenly, probably with +/- 2-3 tenth of a degree.

Most people get -1.2 or so when they install the crash bolts. I'm not sure what methods they used to max out the camber, but I'm guessing they simply pushed the upper rotor towards the center of the car with their hands.

My mechanic maxed out camber by using the weight of the vehicle as leverage.

Make sure to replace the OEM bolt with the OEM crash bolt FIRST before you do the following.

-Jack up the front of the car
-Loosen the 2 19mm bolts holding the hub to the knuckle
-Place a wooden board that's about 4'' tall on the outer edge of the tire.
-Lower the car so that the tire's outer edge sits on top of the wooden board.
-The weight of the car combined with the board pushing in towards wheel should max out the camber.
-Tighten the 2 19mm bolts.

Your toe will most likely change when you change the ride height. Even if nothing else was changed on the suspension, the factory toe setting most likely won't be "aligned". If I recall, the assembly line only checks the alignment every nth car.

[supramkivtt2jz]

Originally Posted by ayau

Your toe will most likely change when you change the ride height. Even if nothing else was changed on the suspension, the factory toe setting most likely won't be "aligned". If I recall, the assembly line only checks the alignment every nth car.

our cars toe-in 1/32" in the front for every degree negative camber gained.

our cars also gain camber when lowered. it would be reasonable to assume they toe-in when lowered as well

[ayau]

Originally Posted by supramkivtt2jz

our cars toe-in 1/32" in the front for every degree negative camber gained.

Is that negative camber gained from suspension compressing (I'm guessing it is) or the rotor tilted in from the installing the OEM crash bolts?

Originally Posted by supramkivtt2jz

our cars also gain camber when lowered.it would be reasonable to assume they toe-in when lowered as well

I believe that's only to a point for McPherson struts. After a certain point of compression/drop, you actually gain positive camber. I'm not sure about the camber curve for the rear multi-link.

[Philly758]

Ayau, thanks for the response.

Originally Posted by supramkivtt2jz

our cars toe-in 1/32" in the front for every degree negative camber gained.

our cars also gain camber when lowered. it would be reasonable to assume they toe-in when lowered as well

Soooo, if this is true, when you are driving down the road and you suspension compresses, camber increases (to a point) and you get more toe in? I would think toe in would remain the same or you would get some funny wear from to toe constantly going in and out on the highway.

Edit: More thought... This probably has to do with the caster, thats why the toe changes with camber? (learning on the fly here)

[Gunman]

Toe change is due to either the steering link (front) or toe link (rear) being a fixed length, and moving in an arc, which is a different radius than the arc the wheel/tire/upright is moving, much like "bump steer".

[Philly758]

Aaah that makes sense. As the camber increases, the top of the wheel wants to get tighter to the car and the bottom wants to get further away, so the tie rod connecting to the front of the hub (on the bottom half of the wheel getting further away) at a fixed length will pull it in. Creating toe in. Got it.

[Steve]

Installed swift springs 2 weeks ago.

For rear, SPC LCA's ($220), brought the rear back to stock spec.

For front, nothing, got half a degree of negative camber after lowering.

[Figo]

Can anyone give me a link of those "crash bolt"? BTW, since we r going to do the four wheel alignment after changing lower springs, do we get things like crash bolt and ask mechanists in the store to change camber for us? I am going to do it at SEARS.

[console_cowboy]

Originally Posted by Figo

Can anyone give me a link of those "crash bolt"? BTW, since we r going to do the four wheel alignment after changing lower springs, do we get things like crash bolt and ask mechanists in the store to change camber for us? I am going to do it at SEARS.

The crash bolts are available from Subaru for under $10. They are a factory bolt that replaces the upper strut bolt (there are two). The factory bolt in that location has a thickened shank and the crash bolt has a normal sized shank. This allows you to push the strut to adjust your camber. You should install these with the springs and have your alignment techs loosen them to adjust each side of the car. Whiteline and SPC also make crash bolts which should gain you some additional camber, but their torque settings are much lower, around 70-80ft/lbs vs 116ft/lbs for the factory crash bolts. Honestly, I think your tire size will limit how much camber a bolt can get you up front before the size of the bolt will, so I would go with the much cheaper OEM crash bolts.

[regal]

What about tread wear? With rce yellows or swift springs and max crash bolt front camber will you maintain stock treadwear or will it be new tire time every 10k miles (assuming you don't skid around or do burnouts.)