No problem John. Just happy to help. It's not often you can give personal experience with something like a fire system. I hope my experiences in that are are done and I hope all you ever have to do is wax the bottle!

Patrick,

Awesome build.. The Cobra has been on my "Want To Build" list for a long time. I'll be subscribed to your thread.

I know exactly where you are coming from. I have read and researched for a long time. The Holy Grail is obviously not out there or everyone would have the same setup already. I was hoping to extract some information to help the folks that are caught up in the marketing wars and really don't even know where to start looking to develop the headache we have all had. But after a couple asprin and some time, this suspension thing is alot of fun. It is very satisfying to have conceived and built a chassis that meets or exceeds your personal goals for it.

Later,

Bump Bump

Sorry Ted, I am a bit under the weather. I am hoping to keep this going. I hope Matt, JP and others are working on some ideas. I am going to take a stab as well, but frankly until I kick this bug I'm just not up to it. Hopefully some others will jump in.:lateral:

Later,

Not that I have any more info then the next guy these are some things that I take into account when setting up some of these suspension numbers.

1. Overall tire height
2. Widest Track width possible with given tire height and ride height of
vehicle, The fender over hang, or how much the tire tucks affects this.
3. Desired Suspension design to be used Mustang II or corvette, ETC
4. Physical contraints of the car, size of car, spindle vs desired rim size.
5. Avaliblity of rack and pinion for proposed narrowed suspension geometry
or will you have to do a custom width rack.
6. If your building you suspenion to an already avalible rack width then more then likely you will have to adjust your suspension track width to optimise. We do this in Solidworks. You must also take into consideration the steering arm height of the spindles and how that rack location will affect engine mounting and Engine dampener clearance.
7. After you have figure out all these different issues, you must decide what specs can and would like to have in your suspension. Do you want a high roll center or a low? What kind of camber gain are you looking for? The length of the upper control arm determines this along with the static angle it is mounted at.
Roll center, upper control arm to lower control arm ratio, instant center, anti-dive, scrub radius, and an million other things that all affect each other. If your using alot of stock parts things like ackerman and King pin inclination and overall spindle height are already determined.




Then once you think you have it all figured out, you find out the suspension will not droop enough to get the back tires out so back to the drawing board so you don't have to drop the rear trans axle to get a tire off.


Interesting thread but my head hurts.

I'll Chime in with my .02, I went through this whole exercise a year or so ago, reading everything I could read and asking everyone I could ask. There is no Ideal, just a mixed bag of trade off's. 1st trade off is that you got to get the motor in between there somewhere, second the wheels and tires can't stick outside the fenders (in our version of the sport anyway)

I started with the wheel's and tires I wanted to run, 17x9.5 Z06 wheels. Second was the overal width of the track so I won't rub the fenders. I knew I wanted to run stock Corvette (C5) parts, so the spindles and control arm dimensions were fixed. But to get this config under the front of my camaro it ended up being about 5" narrower than the stock vette geometry. So I had to go back to the drawing board and refigure all the geometry with the new track. I ended up with the roll center about 1.5" above ground. From there I tried to optimize camber gain and minimize bump steer. The Rack location is the hardest part, With some help from Matt at AME we came up with a solution to lower the mounting points on the control arms and get the rack low enough to clear the engine. I also set my engine back about 1.5 inches so that the rack sits in the "sweet" spot behind the balencer and in front of the pan. Every 1/4" helps.

Everything on my suspension is adjustable, lower control arms, upper control arms, tie rod mounts ect... I havn't driven the car yet so I can't give you any real world feedback, But I will say that My Daily Driver Trans AM that I auto x with is a handful on the street in full auto X trim. There are to many inperfections in the road, it wants to dart off in any number of directions and rides like a brick. After every event I dial back down the shocks to a softer setting to make it bearable.

My Two cents, hope it helps.

Just curious, why not use a program like WinGEO? Solidworks can be very cumbersome for assemblies like that.

Roger,

I use and love Solidworks as well, but I agree with Matt. I use specific software that just crunches the geometry numbers. Much quicker to do "What Ifs" IMO. What's your motivation on this one? I'd like to hear you wrote some cool Macro that you are willing to share to automate this process in Solidworks.:_paranoid

The initial base for this thread was to try and answer some of these questions or at least give folks some legitimate targets. Alot of guys can choose alot of parts and put them together, but have no idea what the end target should look like. I think we are turning on some light bulbs with regard to this stuff.

Your complete post just gave alot of information that I guarantee guys that spent thousands of dollars on parts never even considered.

My head hurts too, literally I'm still sick! Crap.

Thanks for jumping in Roger, your thoughts are well respected around here.

Thanks for jumping in. You just solidified some points made earlier. Most people get wide eyed at all these trick race parts and just have to have them. What they don't realize is they may be building the most untamed, kidney busting street car they ever saw. It is no fun. Where I live in South Western PA, the roads are terrible. We are the pothole capital of the country! I have a friend with a tire shop, he just told me last month he replaced 3 factory wheels on SUVs because the owners hit a pothole and bent or broke the wheel. Imagine driving your race car into one of those!

Anyway thanks for the input, this just adds more credibility to what is being said in this thread.

Later,

I use Solidworks because I have it and can turn the design in Soildworks into plates to machine out to make different crossmembers for suspension. I realize that there are better programs for suspension, but it all boils down to numbers. I don't need the program to tell me what the instant center is, I know the point where the upper and lower control arms intersect is the instant center and solidworks well tell me that number.


There were guys haulin ass with kick ass suspensions that they drew on the floor with chaulk. Todays modern suspensions have just be refined to the point that they test and tested. Computers just make that easier and quicker. You still have to be 2% smarter then the program your using.

I still have a piece chalk in the tool box! Don't forget the string! You hit the nail on the head, it is just quicker. 2% smarter, I quit! :lol:

Later,

As far as respected, I don't know about that, we are just lucky and might have common sense which is not so common any more.


I have a 1946 Packard that a customer brought in a while ago that we are going to have to build a complete custom suspension for. No C6 stuff with trans axles, just a 5.3liter LS engine with 4L60E. It will have updated rear leaf springs in the rear. But the front suspension is almost impossible to get parts for and who would want to use it any ways, the steering in those days did not return to center and and was not built to do much over 55mph, maybe. I have looked at using the stock pick up points and build new control arms to those since we lowered the ride height the geometry would be Descent. But the crossmember curves forward to clear the old straight 8 flat head engine. Now I started with the tires he wants to run ( Caddy wire wheels) which have a 28" diameter in the front with the tires. But the wheels only come in a 5 on 5" bolt pattern. So that limits the avalible spindle and brake options real quick. Wilwood had a 13 kit with 5 on 5" pattern with their Pro spindle but those would not clear or even work with a 15" wire. So
I got a set of 98 chevy truck spindles for 100 bucks from the junk yard. They have 5 on 5" pattern stock. I'm working on figuring on the ride height of the chassis and will set the spinldes at the spindle height of the desired tires at the rough track width I'm looking for. Then I will set up the rack at the height the spindle's steering arms. I will then figure out a good upper control arm length and ratio to the bottom to optimise bumpsteer with the standard 24" center AGR rack.

I'm not trying to make a super corner carver Packard, but there is no front suspension kit on the market that I found that will suit my needs so we will build it. Same theory just not as high tech I suppose.

take it for what it's worth, probably not much

Rodger

Cool! Thanxs guys for the input. How about some plus or minus ranges for general guidelines in the street performance range.

Camber gain per inch..................

Static caster..................

Roll center height.................

Bump steer................

Ackerman.............

Anti dive %..................

How about some software recommendations?

Where do you guys source specs from for stock components?

Which stock components do you like to work with? I will assume C5/C6 as one option that works well?

Which after market components or sources do you guys like? (ARG, Maval/Unisteer, Stock car products)?

Who is will to do consulting work in this area for a fee?

Numbers?:)

John

I second the motion! I'm finally free from the bug that held me down and am trying to do some work on this. But, what I think the numbers should be are not what people want. Where are you suspension guru guys? Please don't stop the enlightenment! :D

YEAH! Don't stop!

We're still trying to take the pebble from your hand!:lol:

http://i56.photobucket.com/albums/g1...whenpebble.jpg

John

I'd love to provide a "general" list of specs, but I can't really. I have to do that on a case-by-case basis.

You could say the specifications I listed previously works for vehicles similar to a well-prepared first-gen Camaro. I wouldn't stick it on a Chevelle or a '55 Chev if you wanted the best of performance. But honestly, you could put it on most vehicles and just swap springs and ARBs to match the new vehicle.