I have a stock scrub radius, with 315s. I also have adjustable ackerman.
Track width has no relevance to ackerman.

As far as what you've seen, sounds to me like your recollection of events changes weekly. You have more stories than a choose-your-own-adventure book. But hey, an active imagination is good.

And everyone has gone SLA? Who told you that? Sounds like your mentor is giving you bad information. As good as the information they've told you about how suspensions work. Maybe it's time to find a new mentor, or maybe pick up a book.

 

Should I embarass you and post up all the email questions you sent me a few yeas ago on Facebook when I was teaching you this stuff?

If Ackerman is off, the wider tires only make the problem worse with leverage at the extremities as the wheels are dragging on an uneven footprint. It will and does wear the crap out of your tires. It's the whole reason a taller sidewall thnner tire is more forgiving. As for your scrub? You tires sit outside your wheel wells. I have a picture somewhere of this I will try and locate of mutual acquinatance taking a pic of it at the Broiler.

For you to increase SAI to avoid a massive psitive scrub, you have to reduce caster so much your car is squirrely at any attempt of high speed use above 60 mph. I would love to take a video of your car dancing about a lane on a local freeway with your super intelligent butt pucker.

 

The fact you have been one of the largest forerunners on these boards in an attempt to change and correct Ackerman proves my point is correct...

..but you are not that smart to see your hypocritical actions vs words.

 

If the discussion becomes too personal and slides downhill, I'll close the thread.

JamesC

 

This thread has thrown up some interesting insights into third gen suspension design.

 

I've never emailed you. We did communicate on FB though. If you post those conversations, they are going to embarrass you more than they embarrass me. We'll also see where you picked up the idea that ackerman can be important. So be my guest, post em up.

So you saw my car once almost 4 years ago and know everything about it now. Impressive. Let me spare you the work of finding a pic

Look how far those tires are sticking out /sarcasm.

Haha, slow down cooter. Look at this alphabet soup of mistaken assumptions. Who told you this stuff?
At a certain point you need to learn some math. Get a tutor and work through this:
Cm = Cmo + arccos(sin(K)cos(S)) + K + arccos(sin(Cs)sin(S))-180

where:

Cm = camber as a function of caster, kingpin inclination and steering angle
Cmo = static camber at 0 steer angle (negative is top in)
K = kingpin inclination (like caster but viewed from the front, positive is top in)
S = steering angle (negative is inside tire, positive is outside tire)
Cs = caster (positive is top back)

All values are in degrees so be sure to let your tutor know.

That makes something that looks like this

Of course I blacked out the numbers. Giving them to you would defeat the purpose of me giving you homework.
For extra credit, plot the lifting effect that is a result of this. The only hint I will give you is that you need to use some trigonometry.

When you are done with that, consider writiting a brief report comparing and contrasting these numbers with some current sports cars that use Macpherson struts. Lets ignore dual ball joint and revoknuckle/hiper strut implementations for now. Hint: Porsche.

Finally, read chapter 1 of RCVD.


Message to the moderators: This individual (Dean) is a cancer on this forum. There is a reason that virtually every person that knows about suspension and handling does *not* participate here. You let him set the tone here, and it's not a positive one, nor particularly well researched.

 

4 years later and a lot of studying and it aoppears you have the "looks" correct. How much of that car is still 3rd gen? Remember. I was pulling 1.07g's on 8" wide street tires and wiped out the entire crowd you raced against by the same 4 second + margin. Bravo to you. Cost you a lot of time and money just to keep up with me.

its so difficult to run a camber curve. I do in in real life, not on paper- why? Because paper does squat when it comes to tire temps and wheel travel.

edit: For the record, I finished calculus way back in my junior year of HS

 

Cool story.

 

You make like you are such a genius that no one else could possibly do what you do. Here's the real world, not paper equations. I help people here, not throw big words at them

 

The real world is actually owning a thirdgen and racing it instead of living vicariously through others.

Cool car though.

 

Effective discussion requires mutual respect. When there is none, the "discussion" often descends into bravado, recrimination, calumny and general squabbling. Since I don't believe any hope remains for this thread....

JamesC