Jason, I recently added 1. 5" of high density seat foam to the bottom of my seat. It made it quite a bit softer and more comfortable. Look at the article in the TDR a couple issues back by Denny Day, his instructions are outstanding.
Thanks Denny Day!!!!
I went a step further and took the seat back cover off with the intention of adding some side bolster and cushioning low in the back. I have low back trouble too, so some added support would be great. If you take the seat back cover off, be prepared for a battle to get it back on. Only peel it up high enough to get your side bolsters in. I took it all the way up and it is not necessary. It is a PITA to stretch it back over, and the seat foam likes to get out of place just when you are ready to clip the cover. I put a piece of foam in the relief of the seat foam for the seat back upright bars, it was about 12" long (vertical) and about 2" square at the bottom. When you take the seat cover off you will see what I am talking about, the seat foam is molded to the tubular frame of the seat back. I tapered the piece to about 1/2" square at the top end. This added side bolster just like I wanted, but I am driving it debating whether it is too much. The seat is DEFINATELY more comfortable with it in there. I also added a 1" x the width of the seat x about 4" high piece across the low lumbar part of the seat behind the seat foam. This piece needs to taper from 1" to basically nothing over the 4" height rather than 1" thick over the whole height, I can feel the step with my back. I am going to take the cover back off and thin the side bolsters just a tad, and taper the lumbar piece, then I should be set. My seat is way more comfortable now than it was, but I am looking for a tad more improvement.
Let me know if you need more info.
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