Great design, I have a question for you about the lower mounting plate you used. Understanding that the "u" bracket that is bolted to the flat bar, is there a concern about it deflecting under load? Would a machined bar like the one for the top mount resist deflection better?
Not knocking the design, great stuff..just something I see and am curious about.
Keep up the good work!!
The summary first then the explanation. There is no concern about deflection under load. The 'T'-bar design is comparable in overall strength.
Okay, lecture is in session students please take your seats. HAHA. just playing around.
The main thing you want to focus on when taking about bending is the unsuported distance and the cross sectional area. Also the moment of inertia plays a heavy roll as well.
To explain the MOI, picture bending a flat piece of steel 1/8" thick and 2" wide. It is easy to bend it so that the bend is across the 2" width. because you are only bending the 1/8" thick part.
The cross sectional are is the area of the part if you took a vertical cut at the highest load.
The T-bar has more unsupproted distance. Since the force is directly in the center of the bar. My design with the U-bracket brings the forces closer to the A-arm attach points. Therefore, less bending moment. Also since my lower plate is wider than the t-bar I have more cross sectional area. The T-bar would have been a 5/8" diameter bar that is flattened at the ends. Mine is a 2" wide steel bar with a 1/4" thickness. there is no concern about deflection or fatigue.
My design also make the shock mounting points adjustable. I was able to fine tune the amount of droop I wanted, and i was able to dial in where the shock bottoms out compared to the stock bump stop bottoming out. Since this is a drag car i was most concerned about the droop of this
suspension and the spring rate chosen. However it will also be a light use street car and needs to have the ride height adjustable.
The other advantage is my design weighs 8lbs less per side. The biggest saving was my spring only weighs 3lbs.