I just finished installing a new rear "Sway-Away" sway bar on my 1969 IRS pan, a gift from another SOC member (Thanks!).
First the installation impression:
It is a pretty well-thought-out accessory, mounting to the rear torsion tube and attaching to the spring plates on both sides with a 1/4" thick "L" bracket.
The Sway Bar mounting brackets (one on each side) attach to three bolt holes on the spring plates where the plate attaches to the wheel hub casting. These brackets are left and right and can only mount one way, and on the outside of the spring plate.
I found on this kit that the "L" bracket lower section (the horizontal piece that the bar linkage bolt attaches to) was a bit too short, causing two things to happen: (1) Because they're too close to the spring plate, the top washer and upper rubber cushion have to be trimmed (flattened) on one side to allow clearance with the spring plate and, (2) overall, the linkage holes in the brackets are about 3/4" too far apart across the car to allow a straight vertical line of the linkage bolt through the mounting bracket and the sway bar once everything is lined up. If the lower bracket section were about 3/8" - 1/2" longer, spacing both the bar linkage mount holes closer together, everything would line up better.
I found that every bolt supplied in the kit was too short by about 1/2", AND I had to buy new spring plate bolts (3 per side) that were 1/2" longer than stock to accomodate the 1/4" thick mounting bracket (1/4" longer bolts were not available). The supplied bar linkage bolts were 1/4" shorter than the stack-up of rubber cushions, bracket and bar. One inch longer would have been super, but I chose to use bolts 1/2" longer and struggled a bit to get the nuts on.
Once everything was loosely assembled, I tightened the bar linkage bolts as directed, leaving the torsion brackets fairly loose, then got the car off of the jack stands and settled before tightening the torsion tube brackets as directed. With the longer bolts installed everywhere, the whole assembly went together easily and tightened up nicely, as per the instructions.
Driving Impression:
Went out on a pretty brisk morning and hit my favorite local road - warning sign: "1 1/2 miles of windy road ahead" 8>)
I quickly noticed far less steering effort needed for the same turns I've been running all Summer, AND the stability/predictability of the rear end greatly improved. Oversteer was reduced by a lot and the car seemed to track through the turns better, especially when lots of power was applied coming into the turn apex.
Overall, the car, which already handled pretty well with 205X16's on the front and 225X16's on the rear, REALLY started to feel like a big Go-Kart - very nice!!
The down side is an increased harshness in the rear over road irregularities, like cracks and pavement divisions. Not super-bad, but I didn't notice them as much before.
End-to-end (forgetting the trip to the hardware store for new bolts) the bar took about 2 hours to install, including modifying the cushions and top washers to fit. If everything fit the first time, the time would have been a bit shorter.
Just F.Y.I.......Gordon
One of the "Speedstah Guys Rooting for the 'Sox" in Rhode Island
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