structurally speaking. I just put new floors in my 64 and i have a pair of fox seats that i want to install... with the seat riser the seat sits way to high but without it they are perfect. if i omit the riser should i think of adding some braces?

 

If you eliminate the seat risers you should definitely add some structure to take their place. If you look, the front of the seat riser connects the frame extension and floor. This then carries to the sides an into the rocker boxes.

 

Believe it or not, with the unibody design of the Mustang the seat risers are an integral structural piece. Removing them is NOT a good thing. I have late model seats in my '66 and what you need to do is trim the risers down an inch or so, so that the late model seats fit better, but don't eliminate the risers completely. Without risers in place, you're seats would probably sit too low anyway.

Dave

 

they are as important as torque boxes or the roof on a coupe!!! If you want to remove them I would add sub-frame connectors and also connect the new pieces width ways as well as length. It is something that can be eliminated, BUT ONLY IF MAJOR STRUCTURAL IMPROVEMENTS ARE MADE!!!!!!!

 

The driverside box on my 66 was cracked and in bad shape so i ditched it.
I pulled my driver side out and fit my new race seat. Im 6'4" so it isnt to low for me and its on sliders.
As of now I have the bolts going thru the pan into a billet block. I dont like that much. So im fabbing up a .25 Alu plate should look much cleaner.
Im planning on making a front and rear cross section to connect to the sub frame.
Thought i might as well make it a drive shaft loop catcher also.
There is no way im leaving it like it is and I have the rear cage in my car.

 

thats what i needed to know. i tried it out a couple months ago.. had one side replaced without a riser and the other with the old floor. i really liked the way that it felt not having the seat riser it seemed like the rails raised it up enough for me. i'll just look into adding some cross braces before i continue working on it

 

BTW you will be cutting the hump out of your carpet if you ditch the risers nbd ill just glue it in place under the seat.