I know this would be much better with pictures, but I've been unable to upload any because my internet connection is too slow (satellite sucks!). They just time out.
Anyway, I've been working on redesigning my front suspension using the new Wilwood ProSpindle. I don't think I would have tried this had I realized just how invloved it would become, but I'm close to getting the car on the road, so I wanted to give a write up on how it has gone so far.
The design goal was that this had to be bolt in, no cutting and welding. Using the stock pick up point for the LCA, a Moog 772 (OEM Mopar) upper ball joint and a ride height that is lowered approx 1.75 from stock, the drop spindle results in a roll center of 7.75 inch. This is OK for normal cruising on the streets, but not ideal for a corner carver. The wheel rate using a 400 lb/in spring came out to be 205 lb/in.
In order to get the RC in the sweet spot (2 to 3") I will have to lower the pick up point for the LCA 2.5" and use adjustable upper ball joints to raise the upper ball joint pivot point about a 1/2". Lowering the LCA pickup 2.5" will require a new centerlink and possibly a new centerlink adapter to keep the bumpsteer in check. The good news is that this would virtually eliminate the moment arm acting on the rack and pinion so I shouldn't need any kind of anti-torque guide.
I'm using a prototype -10 degree steering arm right now, which required a 1/2 inch wheel spacer to clear the ('94-'04) 17x8" wheel. I'm going to try a new design with a -12 degree ackerman and just a little less length in order to clear the wheel better. The use of a wheel spacer resulted in a 3.25" scrub radius and a track width of 58.125".
An 18 inch (even an 18x9") wheel would clear no problem, but I don't like the look of an 18" wheel on the early cars. I accept the look of a 17" wheel as I feel form follows function, and a 17" wheel provides the perfect balance of weight and tire aspect ratio IMO. I might use 18" wheels at the track once I correct the roll center as I could get rid of the spacer to shorten up the scrub radius. With a P275 tire on a 9" rim I would need to use some sort of wheel stop to prevent the tire from contacting the frame in a full lock turn (not something that's required on a road course anyway) so I would only use them at the track.
The main design goal for using the drop spindle in the first place was to utilize a shorter steering arm to improve the turn radius, and a secondary goal was to fit inside a 9" wide wheel. I haven't driven the car yet with the new suspension, but judging from the angle of the wheel at full lock the turn radius will be excellent, on par with any modern car.
Wilwood also has a non-drop spindle that uses a bolt on steering arm that would be much easier to adapt to the early Mustang chassis. I will just have to give up on the 9" wide wheel.
I will post pics as soon as I can.
Anyway, I've been working on redesigning my front suspension using the new Wilwood ProSpindle. I don't think I would have tried this had I realized just how invloved it would become, but I'm close to getting the car on the road, so I wanted to give a write up on how it has gone so far.
The design goal was that this had to be bolt in, no cutting and welding. Using the stock pick up point for the LCA, a Moog 772 (OEM Mopar) upper ball joint and a ride height that is lowered approx 1.75 from stock, the drop spindle results in a roll center of 7.75 inch. This is OK for normal cruising on the streets, but not ideal for a corner carver. The wheel rate using a 400 lb/in spring came out to be 205 lb/in.
In order to get the RC in the sweet spot (2 to 3") I will have to lower the pick up point for the LCA 2.5" and use adjustable upper ball joints to raise the upper ball joint pivot point about a 1/2". Lowering the LCA pickup 2.5" will require a new centerlink and possibly a new centerlink adapter to keep the bumpsteer in check. The good news is that this would virtually eliminate the moment arm acting on the rack and pinion so I shouldn't need any kind of anti-torque guide.
I'm using a prototype -10 degree steering arm right now, which required a 1/2 inch wheel spacer to clear the ('94-'04) 17x8" wheel. I'm going to try a new design with a -12 degree ackerman and just a little less length in order to clear the wheel better. The use of a wheel spacer resulted in a 3.25" scrub radius and a track width of 58.125".
An 18 inch (even an 18x9") wheel would clear no problem, but I don't like the look of an 18" wheel on the early cars. I accept the look of a 17" wheel as I feel form follows function, and a 17" wheel provides the perfect balance of weight and tire aspect ratio IMO. I might use 18" wheels at the track once I correct the roll center as I could get rid of the spacer to shorten up the scrub radius. With a P275 tire on a 9" rim I would need to use some sort of wheel stop to prevent the tire from contacting the frame in a full lock turn (not something that's required on a road course anyway) so I would only use them at the track.
The main design goal for using the drop spindle in the first place was to utilize a shorter steering arm to improve the turn radius, and a secondary goal was to fit inside a 9" wide wheel. I haven't driven the car yet with the new suspension, but judging from the angle of the wheel at full lock the turn radius will be excellent, on par with any modern car.
Wilwood also has a non-drop spindle that uses a bolt on steering arm that would be much easier to adapt to the early Mustang chassis. I will just have to give up on the 9" wide wheel.
I will post pics as soon as I can.