chamber plates: ??

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[5speedcobra]

Would these be univeral? And also where would I be able to buy them?

I am wanting to get chamber/caster plates for my 87 Daytona.

thanks!
Cris

[GrantC]

I know what a chamber pot is, but I doubt that's what you're looking for, or related.

Do you mean a tophat for a macpherson strut suspension that lets you adjust camber? (ie. Camber plate)

I don't think they're universal, since they have to have the correct bolt pattern on top to match the hole in your shock tower, and they have to have the correct diameter & top spring perch for your suspension...

[GrantC]

Okay, a quick google shows I was wrong, there are "universal" ones, all you have to do is cut away the top of your strut tower & install the camber plate.

http://www.csracer.com/camberplate.html

^--- Shows it being done on a Dodge Daytona

[unclebilly]

Do you mean camber plates or chamber pots?

Camber plates are used to adjust your suspension, chamber pots are something you put under your bed in case mother nature calls in the middle of the night...

[unclebilly]

By the way, I think chamber pots are universal.

Looks like Grant and I have a similar sense of humor...

[5speedcobra]

Okay, a quick google shows I was wrong, there are "universal" ones, all you have to do is cut away the top of your strut tower & install the camber plate.

http://www.csracer.com/camberplate.html

^--- Shows it being done on a Dodge Daytona

That site is where I got my idea. haha. Im just wondering where i'd buy them. I'm willing to do a bit of custom work to make them work if I have to. not a big deal. I emailed the guy, maybe he could tell me where he bought his, but havent heard back from him.

[RSX-TACY]

camber bolts might be quickest/easiest.

Depending how "bad" your current steering angle inclination is, adding camber plates might not be so beneficial in corners.  Meaning if you have too much SAI, it'll be counter productive and may require you to run high static camber to get any benefits.  Whereas if you use camber bolts, generally it won't affect your SAI.  Good thing about camber plates though is it puts your struts at a greater angle which may allow you to add much larger wheels/tires than what you would normally.

[samol_hok]

adjusting camber from the top would completely change steering angle incline
remember sai is the imaginary line from the top mount all the way to the lower balljoint

[randedge]

Since slanting struts to gain camber changes KPI, you are going to have to dial in some caster.

Most pertinent point in caps lock and boldened.

Originally Posted by Vancouver Special

WARNING: Long answer

If you are looking for a quick number, I would say anything less than 10 degrees is within the acceptable window.

To understand minimum caster required, you will need to consider KPI (king pin inclination), since both of them work to cancel each other. KPI is the angle (looking from the front or the rear of the car) formed by drawing a line between the upper steering pivot and the lower steering pivot and the angle between this line and the true vertical is your KPI. The problem with KPI is that if it is anything over zero, your outside wheel will start gaining positive camber with any steering input (this is assuming there is no body roll at all). The easiest way to visualize this is to cut a right-angle triangle (one side 3" and the other side 8") out of a piece of paper and play with it. Keep the right-angle at the upper right side and touch the bottom point on a table with the right side perfectly vertical. The sloping side (left side) is your KPI and the vertical side represents the face of the wheel (tire). Now, turn the triangle slightly while keeping the sloping side still. You will notice the vertical edge starts gaining positive camber. This behavior is exactly opposite to what caster will do. Most of you know if there is positive caster (like the front fork of a bicycle), your outside wheel will gain negative camber when you turn the wheel. Therefore, from a wheel camber change point of view, KPI and caster actually work against each other. Because of packaging constrains, all cars will have some amount of KPI (typically a few degrees on the low side to mid-teen on the high side). For strut type cars, KPI is defined by the upper strut pivot and the lower ball joint. Since the tire's inner side wall has to clear the coil spring, most strut cars (except Hondas from the '90s) would have an above-average KPI. Even with zero body roll, this geometry would induce positive camber every time you turn the steering wheel. Most of you add static camber to combat this behaviour. However, when you think about it, how do you add the static negative camber??? By tilting the upper strut inwards some more, which adds more KPI yet. Crazy, isn't it.

Now, let me tell you a little secret. FOR EVERY DEGREE OF KPI, YOU WILL NEED HALF A DEGREE OF CASTER TO CANCEL THE KPI CAMBER INDUCING EFFECT. How you achieve that is your business but when the top of the strut tilts inwards, it should be accompanied by tilting it backwards (you will notice that some strut cars, like BMWs, have the strut tilted backwards from the factory, does anyone here know what kind of caster they run???). If you add in the body roll effect, you will come to the conclusion that there is never enough negative camber and putting in as much caster as you can will be a good thing. Steering effort with increased caster can be reduced by moving the wheel axle ahead of the king pin (this is call pin-lead, which would decrease the distance between the tire's contact patch and the theoretical point where the king-pin passes thru the ground). Car designers would do that if they know ahead of time that they will use a lot of caster. The next best thing is power steering. Without power steering and pin-lead, most drivers will find it difficult to steer the car when caster angle approaches 5-6 degrees, especially with wheels that have a smaller negative off-set than OEM wheels (more scrub radius). A shorter tire will minimize the steering effort for a given caster angle.

In regards to Ground Control's article on corner weight effect due to large caster settings, someone asked the same question at Alex's tech session at last month's club meeting. It is true that "theoretically" caster would effectively lift the outside front tire up and thus transfer more weight to the inside front as well as outside rear tires. In practice, most production autox cars (without a fully triangulated welded cage) are just not torsionally stiff enough to make this a big deal or noticable. In fact, I think a slightly higher loaded outside rear might not be a bad thing for a FWD car.

Joe

The full thread here.

http://vcmc.ca/forum/showthread.php?t=1195&highlight=Camber+Caster

[5speedcobra]

Thanks for the information!
so what I'm learning (please correct me if I"m wrong) that by adding more negative camber by using my car's stock adjustment where the hub bolts to the strut, I wouldn't be modiffying the KPI, therefore not adding any more positive camber upon steering imput...esentially adding neg camber without the ill effect of modifying the kpi.
But, if I got the camber plate that i'm looking for that has adjustments for both camber and caster, I could reach the same effect. by adjusting the caster accordingly to the chamber (thanks for the triangle example. I prob looked retarded playing with a piece of paper at my desk. haha)

My new question tho, if I had -1.5 degree of camber by adjusting from the stock adjustments, or -1.5 degrees from adjusting with a camber plate and the caster accordingly,(ignoring the ammount of work, and money spent on putting in chamber/caster plates) would one be better than the other?

[RSX-TACY]

I would say -1.5 camber from stock adjustments mostly because it wouldn't affect or SAI/KPI.

If a car was bone stock and I was forced to choose between adding a degree of caster or a degree of negative camber, I think I would go with the negative caster.  If you can run alot of negative caster, that's good because then you can run less static negative camber.

[5speedcobra]

makes sense. Now the only thing I'll have to see is if my stock suspentsion can go to -1.5 on the front. We'll see. haha