Gpatrick.... Very well said.

No, some practical experience in a test lab that did a lot of work in automotive design and testing but primarily the school of hard knocks.  I had an 85 Mustang that I managed to make uncomfortable enough that it was no longer fun to drive and it still didn't handle because it is hard to make a street car a race car and still drive it on the street.  Almost mutually exclusive.  So I learned a lot the hard way and am trying to avoid the same mistakes on the 66.

In the lab we would determine the static and dynamic stiffness of the complete suspension system and components and essentially find the weakest link - which was often the attachment point to the frame or unibody.  Any stiffness in bushings more than the weakest link, for example, only served to make the suspension noiser and harsher with no improvement in handling.

When the manufacturers produce autos for the masses, the compromises usually don't swing in the favor of the enthusiast.  The work we did experimentally is now fairly easily modelled which allows the designers the ability to optimize the whole system which has produced some cars with pretty amazing handling compared to decades ago.  Improved suspension attachment points allow refinement of the rest of the system.

I still have a lot to learn on geometry in steering and handling.  I think it takes the ability to think in three dimensions and I struggle with two.

Two interesting articles/sites regarding torsional stiffness.  I think both have shown up here from time to time.  I am thinking about a roll bar with removable links for autocross on my convertible as there doesn't seem to be any other way to make up for a lack of roof.  The one link looks at static torsional stiffness and sees only significant results from the monte carlo brace but some of this is because of where the torque arm is attached.  Might be more interesting if it had connected at the LCA as a significant amount of flex he is measuring is only in the front frame section - hence no observed improvement from torque boxes.  You have to measure where you need the stiffness.  Still it does show that a good monte carlo bar helps.  The articles seem to dismiss subframe connectors as they attack beam stiffness.  They may not help handling but they tie the front and back of the car together and aid in handling extra/excess horsepower if tied in properly.  Interesting reading out there with some googling but there is also a lot of conflicting information/opinion.

 

Last edited by GPatrick (6/27/2013 11:38 AM)

GPatrick wrote:

Two interesting articles/sites regarding torsional stiffness.  I think both have shown up here from time to time.  I am thinking about a roll bar with removable links for autocross on my convertible as there doesn't seem to be any other way to make up for a lack of roof.  The one link looks at static torsional stiffness and sees only significant results from the monte carlo brace but some of this is because of where the torque arm is attached.  Might be more interesting if it had connected at the LCA as a significant amount of flex he is measuring is only in the front frame section - hence no observed improvement from torque boxes.  You have to measure where you need the stiffness.  Still it does show that a good monte carlo bar helps.  The articles seem to dismiss subframe connectors as they attack beam stiffness.  They may not help handling but they tie the front and back of the car together and aid in handling extra/excess horsepower if tied in properly.  Interesting reading out there with some googling but there is also a lot of conflicting information/opinion.

I posted that Julian's link on the old forum a while ago in a thread of yours. I'd like to take the coupe to some flavor of 'Phase 2' but it will be a little while before I'm ready to dig in that deep. One of those things I'm looking forward / not looking forward to doing. The cowl/A-pillar re-inforcement will be a little challenging with MS power booster and cable clutch setup. I think I also posted this one on the old site of another take on installing the vert rockers although the page has been truncated a bit since then:

http://www.streetortrack.com/files/pictures/vert_inner_rockers/vert_inner_rockers.htm

No roof does make the vert challenging but that roll bar should be a project!

That Stangnet post is interesting. I'd say the most notable improvement after installing a bigger front  stablilzer bar shortly after getting my car was the addition of the Export/Monte Carlo brace a few weeks later. Instantly noticeable difference, within the first 500ft of driving really, in the way car felt. I also installed a lower crossmember that ties the LCA mounting points together at the same time.