Submitted by Jon Vez
Following is the procedure I used to install a backstay adjuster on my 1999 320. This method requires no drilling and will work fine if you use a bimini.
The 320 has a substantial masthead type mast with no real ability to bend, so the purpose of the adjuster is not to induce mast bend, but to tighten the forestay when sailing upwind. Tightening the forestay allows you to point higher, reduce heel, and lessens the tendency to round up in strong breezes.
This configuration also allows you to back off the tension on your backstay for improved sail trim when off the wind. Many sailors see a backstay adjuster as an upgrade just for racers, but I believe that this upgrade is equally compelling for cruisers as well. Having a well trimmed boat with less healing and better upwind performance simply adds to the pleasure of sailing!
To create the attachment points for the adjuster, you will simply replace the clevis pins at each backstay tang with a D shackle. The pin that comes with the D shackle replaces the original clevis and the ‘D’ portion becomes your attachment points for the adjuster’s blocks and tackle.
I chose to create an adjustment on each side of the backstay. I originally took this approach to increase purchase, but there is the added benefit of creating less clutter in the cockpit. The starboard side is my ‘course’ adjustment and the leeward the ‘fine’ adjustment.
The actual installation time was about 3 hours for two people including tuning the rig.