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[I figured I would post this up in tech, since I believe the discussion is generic to different options for installing longer-travel shocks.]
Credit for this idea goes 100% to @Downey. It has been a very long time now, but IIRC Jim originally designed this product in about 2001, concurrent with his version of the cantilever shackle. Like so many other of his products developed in that time frame, my 68FJ40 was the guinea pig for the prototype.
The principle was simple: get more shock, and more shock travel, and retain the original shock geometry, without having to remove the stock tower. The Ford shock tower option was already well known in the off road forums, but it had and still has two major drawbacks. First, the extension principle was and is limited by the fact that the top of the tower is stuck underneath the fender. The second is that the shock is significantly outboarded, which is a non-starter for anyone who is using factory-type steering which incorporates a drag link that runs along the framerail.
Jim's design [and mine] uses two plates. The first is the extension plate, which is welded to the rib in the stock shock tower, providing an extra five inches of height to the upper mounting pin. The second is the stabilizer plate, which utilizes the stock tower pin hole to help anchor and support the tower extension.
It was probably good that the prototype was developed on my F engine, as the air cleaner clearance issue does not exist on the 2F. After he delivered my installed prototype (complete with newly dimpled air cleaner) I thoroughly tested out the truck at a nearby OHV area. Considering how basically stock my truck otherwise is, it was impressive that I could now put one tire up on a 30” rock with the other tire on the ground, courtesy of the cantilever shackles and shock towers.
I took a second set from Jim in about 2004 and tweaked the specs on them before installing my version of a prototype on my 64FJ45. My version took away the adjustability feature that Jim had originally put into the brackets, but made sure the tower would not interfere with the drag link and also gave a better margin for clearing the F engine air cleaner. I had a production run made in 2005 and then...nothing. I got waylaid by the tragedy of a friend's death, and just kind of mothballed the project, saying 'One day I'm going to do a write-up on these and give them a proper roll out. So here we are, 12 years later! The warehouse fire has been a personal catalyst on many fronts, and this is one of them.
Credit for this idea goes 100% to @Downey. It has been a very long time now, but IIRC Jim originally designed this product in about 2001, concurrent with his version of the cantilever shackle. Like so many other of his products developed in that time frame, my 68FJ40 was the guinea pig for the prototype.
The principle was simple: get more shock, and more shock travel, and retain the original shock geometry, without having to remove the stock tower. The Ford shock tower option was already well known in the off road forums, but it had and still has two major drawbacks. First, the extension principle was and is limited by the fact that the top of the tower is stuck underneath the fender. The second is that the shock is significantly outboarded, which is a non-starter for anyone who is using factory-type steering which incorporates a drag link that runs along the framerail.
Jim's design [and mine] uses two plates. The first is the extension plate, which is welded to the rib in the stock shock tower, providing an extra five inches of height to the upper mounting pin. The second is the stabilizer plate, which utilizes the stock tower pin hole to help anchor and support the tower extension.
It was probably good that the prototype was developed on my F engine, as the air cleaner clearance issue does not exist on the 2F. After he delivered my installed prototype (complete with newly dimpled air cleaner) I thoroughly tested out the truck at a nearby OHV area. Considering how basically stock my truck otherwise is, it was impressive that I could now put one tire up on a 30” rock with the other tire on the ground, courtesy of the cantilever shackles and shock towers.
I took a second set from Jim in about 2004 and tweaked the specs on them before installing my version of a prototype on my 64FJ45. My version took away the adjustability feature that Jim had originally put into the brackets, but made sure the tower would not interfere with the drag link and also gave a better margin for clearing the F engine air cleaner. I had a production run made in 2005 and then...nothing. I got waylaid by the tragedy of a friend's death, and just kind of mothballed the project, saying 'One day I'm going to do a write-up on these and give them a proper roll out. So here we are, 12 years later! The warehouse fire has been a personal catalyst on many fronts, and this is one of them.
