Front suspension design input needed

[358Mustang]

So I am looking for some geometry input for the front suspension on my mustang. Here is the hub/spindle I was going to use.. It is a stock car products 8 degree spindle.. Balljoints look to have roughly 8" of seperation.

I am also planning on going front steer (which those spindles are)

I plan on running a 315 tire and an 18" wheel. I am also doing tube from the firewall forward, so my design is more or less wide open... I am just not sure exactly where to start. I can start plugging in some numbers, but as far as figuring out an ideal camber curve?? Not sure where to start. I know alot of that has to do with the roll stiffness of the car but again I am pretty much building it all so that is wide open..

Some pointers would be nice

[tigerchevelle]

I would try talking to ron sutton,he has a direct number on his website,ron is a super cool guy.

[Ron Sutton]

Hey Brian,

When you said you were going to design it yourself, I thought you had a plan. What kind of questions do you have?

Ron Sutton

[carbuff]

My suggestion:

Work with Ron and pay him to help you with the design phase. I recall him telling me that he offers design services which can range from individual components to the entire car, at what I considered to be very reasonable prices. He can spec out the pieces to pull together the entire system to give you what you want, then you can take that information and build it yourself. Sort of the best of all worlds if you ask me (design knowledge from someone who has infinitely more knowledge than any of us will ever amass, and the satisfaction of taking that knowledge to build something with your own hands).

Best of luck!

[Rod P]

I agree; work with Ron, be a sponge and absorb it all, don't argue your point (you don't have one) unless you have 32 years of race car and chassis design under your belt, be honest in expectations to monetary limitations, and be patient, building from scratch takes time

[358Mustang]

I just don't know what baseline numbers to shoot for, camber gain, roll center height etc.

[Ron Sutton]

Originally Posted by 358Mustang

I just don't know what baseline numbers to shoot for, camber gain, roll center height etc.

Gotcha.

Have you decided if you're going the conventional suspension strategy route with low front travel & high roll angle (stiff springs & moderate sway bar) or to the modern high front travel & low roll angle strategy (soft springs & big bars)?

I ask because the optimum roll centers are very different.

Brian, if you have an idea of what you're going to do spring & bar wise, share that, and that will help clarify things. Thanx !

[358Mustang]

Originally Posted by Ron Sutton

Gotcha.

Have you decided if you're going the conventional suspension strategy route with low front travel & high roll angle (stiff springs & moderate sway bar) or to the modern high front travel & low roll angle strategy (soft springs & big bars)?

I ask because the optimum roll centers are very different.

Brian, if you have an idea of what you're going to do spring & bar wise, share that, and that will help clarify things. Thanx !

So in order to couple with the rear setup I have got.. I am running a home made 3 link in the rear, roll center is about 8". coilover shock behind the axle, with a 300# spring. It needs more roll stiffness in the rear I feel, maybe due to the angle I have my shocks kicked in at... So my plan was to add a rear sway bar to that.

I just mention the rear because obviously I need them to work together. I am thinking I probly want to go with a little stiffer of a spring up front to limit front travel. I am trying to get the CG down and planned on having the motor fairly low. SO I guess that would fall towards the stiffer spring, softer bar category unless you can say why the other way is better..

I am unsure exactly on spring rate, I would thinkg of starting in the 450-500# range... Coilover mounted as far towards the tire as I can within reason

[Mike Maier]

Ok' I'm gonna through my two cents in. Long as you can on the lower arms. This is dictated by the width of the steering / center link you are using. upper arms will be as long as possible while still achieving the camber gain you are striving for. Roughly .7 pr. inch will be pretty good. Roll center should be lower than 2", no lower than groundish. Yes I said groundish. Your front springs combo's look good but the rear is too low. Do not confuse spring with bar, two different tools.

Just saying

[358Mustang]

Originally Posted by Mike Maier

Ok' I'm gonna through my two cents in. Long as you can on the lower arms. This is dictated by the width of the steering / center link you are using.

So the rack I am using, the tie rod mount points are 18" center to center, so I would want my lowers to mount close to or on the same horizontal spacing as that to minimize bump steer, right?


upper arms will be as long as possible while still achieving the camber gain you are striving for. Roughly .7 pr. inch will be pretty good. Roll center should be lower than 2", no lower than groundish. Yes I said groundish. Your front springs combo's look good but the rear is too low.

When I was talking about bar, I was thinking about adding a rear sway bar.. I got to the point where I was un sure if I should keep adding spring (coil spring) rate, or add a sway bar to help control roll.

Do not confuse spring with bar, two different tools.


Just saying


Thanks for the input Mike.

.....