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No it did not take 20 minutes!
I primed and painted it Friday, so rust might be reduced.
The old bar removed ok, except for one bolt that got a candy cane twist on the way out. The top zinc plated nuts did a good job of keeping the unplated threads rust free, but the threads above this were quite rusty. No sign of the rust preventer I put on there in 1995.
The mounting faces of the stock bar were not machined or ground. The as forged bar did not have good bolting faces. These allowed for water to get into the pass thru section and the one tight bolt was about 1/3 gone from rust. Water was getting into there and causing rust. There may have been some fretting wear at the bar to axle interface.
As you cannot put the bolts in from the top under the spring seat, I was not happy putting threads up. The one bolt was not suitable to reuse. So I went to the hardware store and picked up stainless 8x1.25x40 bolts and stainless nylock nuts. No they are not as strong as grade 8 bolts, but a bolt that is severely rusted was not as good as a new grade 8 bold either.
I installed as per the istructions, moving the rack as far back as possible. It can move about quite a bit, as the mounting holes are very large compared to the bolts. The holes were punched, not drilled. So to accomodate the lack of precision, the holes are large. After I got things torqued down, I noticed that the SS washers under the bolt heads were been pushed* into the oversize holes as the bolts were not centered in the oversize holes, as per the instructions. This did not look good, and there was also the issue that this created bending moments in the bolts... which is a not a good thing.
* the washer on one side was actually bent down into the hole, so the bolt load was not evenly distributed. This will create a bending moment. As the bolt is in tension, the bolt will probably not be bend much, but there will be a large concentration in the bolt.
So back to the hardware store. I found some plated square nuts, extra heavy. They were for a 3/8 thread, and were about 3/8 thick! One side was flat, the other rounded off to a perfect size for the SS bolt and washer. So it appears to have a perfect contour from the bolt head washer to the other square face. The square face of the nut is about 3/4" x 3/4".
The 40mm bolts were about 1 cm longer than required, the stock bolts were that long too. So using these square thick nuts as washers made the bolted joint much better than the one with the washer falling into the oversize holes, and the bolt length is also very reasonable at this point.
So, recomendations. You need some very heavy washers under the bolt head to properly accomodate the oversized mounting holes in the SAS sway bars. You can use any bolt that will go through the axle mounting holes, so consider larger bolts. There is probably no need to stay with 8mm bolts. The bolts can be shorter than stock, but if you use a very thick washer like I did, perhaps stock length will be better. Larger OD bolts will also work better with the oversized holes. So with larger bolts, you may not need an extra thick washer. As the threads are up, consider stainless, or take some measures to prevent rust and water penetration. There is probably no need to use metric bolts.
Yes stainless is not as hard as a high strength carbon steel bolt. But SS bolts are get lots of cold work and have rolled threads. If you go to a larger OD bolt than the larger SS bolt will be strong enough compared to the 8mm carbon steel bolts.
I will be monitoring the ability of the 8mm stainless bolts to maintain preload (torque), and will report if there are any problems. Certainly the 22mm sway bar will be creating much larger loads in the fasteners compared to the stock bar.
I will report on driving impressions later. It is definately doing much of what I was looking for. Reduced body roll is very evident. The reduced body roll also has reduced body roll coupled steering dynamics. So there is a definate sensation of having to turn the wheel more to get the same amount of turning. So in some respects, the turn in is less responsive and feels like the back end is dragging along in turns instead of being contributory. That back end steering contribution was a problem under some manouvers. I will have to get used to all of this. Definately have to adapt to these changes.
posted by 208.24.17...
, Mon, 20 Aug 2001 17:52:00, Wed, 22 Aug 2001 09:33:07
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