LoweringFrontEnd

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By Tony Natoli

I just finished replacing all my struts and used the method Les E. Zesigler (LEZESIG, the Alien, see copied below) to properly affix the springs so they would remain aligned between the strut pads. Although I never experienced a problem, this time I was installing Plaia Pivots and felt it was necessary so as not to possibly ruin the Timken Bearings. Both the lowering and pivot installation went smoothly, worked great, and gave me a great deal of self satisfaction.

Some differences and NOTES...


1. His measurements differed a few mm from mine... especially in the overall strut shaft length... at about 30mm. Mine was closer to 180mmm overall, versus the 151mm indicated, but this did not factor into anything detrimental.

2. Simply stated... I cut back the "shoulder" on the shaft and threaded it 7/8 of an inch back further... and then cut off the extra length by the same amount.

3. I used the 12 x 1.25mm lock nuts that were provided with the new struts... which is the same size as the original. I did NOT use a larger 9/16 x 18 nut as Les did. I had a 12 x 1.25 dye, and maybe Les didn't at the time... I'm unsure why he upgraded the size... Caution must be used here when grinding the shaft to size as there needs to be sufficient material left to thread. This also means that the "keyhole" in the "cups" did not have to be enlarged.

4. When I cut the springs... I was able to heat the spring (180 degrees opposite the cut) and bend it with just a PROPANE torch. I heated the area for just a few minutes and then pressed it down hard against a 2 x 4 on my work bench.

Here is my final result: (The rubber "dust cover" was tossed as it was old and crumbling...)

004.jpg

Here are the "phenolic washers" that were replaced by the Plaia Pivots:

005.jpg

I would encourage anyone to attempt this procedure as it indeed satisfies every aspect I was looking for. Performance (improved ride, braking and cornering), ease of steering, correct alignment, and looks.


Cutting Springs. How NOT to use zip-ties. Free Pics.

shock1.jpg shock2.jpg shock3.jpg shock4.jpg shock5.jpg

Images courtesy of ItalianCarClub dot com Thanks Chris

Chapter 3. Strut treatment on lezesig's X 1/9

Cutting the spring length upfront to drop the nose of the X 1/9. Non "coil-over" application using a conventional shock. KYB's shown.

One X 1/9 driver, I won't mention names , related a story about a spring end untrapping and gouging a tire at speed. This led me to believe that there must be a better way to secure cut springs in their perches other than using zip-tie, mallable iron wire, tie wire, bailing wire, stranded cable, etc. I've been mulling this over for about year now and decided to put some plans into motion. The following is the results.

Here is a way that works and works good. It is mechanically sound and does not rely on a zip-tie arrangement or similar restraint to keep a loose spring (once trimmed) on a shock. The original perches now retain the cut spring.

It is an easily repeatable process albeit a little challenging. Not difficult but does takes a steady hand when grinding and arm strength when thread cutting.

In concept, the spring is trimmed to the desired length and the shock shaft is modified to allow the mounted perches to trap the spring at the desired preload.

The modification of the shock shaft is accomplished by merely relocating a stepped feature on the shaft, cutting new threads, and parting excess shaft length. The top hardened cup is also modified by enlarging the keyhole to accomodate a new larger flatted shaft end.

Rudimentry tools are all that are required to perform this modification. Nothing elaborate here, with one exception. That exception being a 9/16 by 18 thread die and handle. I suspect not everyone might have this laying around in normal shop tooling. They are readily available as it is a common thread pitch.

An additional purchase is required of (2) 9/16 by 18 NYLOC hex nuts and (4) 9/16 ID flat washers. One Nyloc per shaft end and two flat washers under each nut. The original nuts and their washers can be discarded. The two flat washers provide the new nut to seat in the top cup appropriately. An alternative is to relieve the base of the nut to seat in the cup appropriately. The cup was designed to receive the stock diameter nut. This new nut is much larger and either requires a relieved base or allowed to sit higher in the cup by the use of the two spacer washers. I chose to relieve the nut and use a single washer but the two washer alternative works just fine too.

shock6.jpg

The flat and slightly nose up attitude look always annoyed me about the stock squatting X 1/9. No more. This cured that attitude for sure. The springs are now securely heldfast under full rebound.

If anybody is interested in trying this method I would recommend a couple of things. First, ensure the shock shaft stays cool during ginding. Second, allow the rebent spring to air cool after heating. Do not quench. Third, file the flats in the shaft before thread cutting. This accomplishes two things. It allows the chips to fall freely and not foul the die and it also reduces the total amount of material that requires removal during the threading process. That factor greatly reduces the amount of force required to thread. One precaution....watch for cross threading when jumping the flats with the die. This is where constant consistant and flat applied forearm strength comes in handy. Backoff a quarter revolution if necessary to allow a chip to fall and clear. Use plenty of oil.

Holding the shaft in a soft faced bench vice prevents marring of the shaft. Copper plate, hardwood, and some plastics work great on soft facing vice jaws.

A couple of things I found surprizing - The spring and the shock shaft are really not hardened much, however the top cup IS ! I suspect they overdesigned the heat treatment required on the top cup. Perhaps the vendor that originally made that cup heat treated all of their small parts. Dunno. What I do know is that a hand file just skips off from the surface of that top cup making it mandatory to grind material away when performing the keyhole enlarge.

Like I metioned to another X driver, Tony in this case, it would probably be easier to do a coil over conversion than this process but this process is doable and acomplishes what I wanted to do with spring trapping. And besides... I am almost as spendthift as the infamous Natoli methodology. I chose to modify the existing rather than buying new parts. There is one downside to this conversion modification and that is the need for replacement. When this shock wears out then the same thing will have to be done to the shaft. Hopefully I'll get a few years and a few thousand miles before then.


If anybody is foolhardy enough to follow me and gets stuck on something.....feel free to post or email I'll try my best to make the project sound more difficult than it really is..... lol


out for now, lezesig '79 X 1/9

PS- Numbers are expressed in millimeters, decimels, and fractions. Thrown em all into the mix.

PS2- Dropping the front end changed the Toe setting by 5/16. It went from 2/16 toe in to 3/16 toe out. The front toe was reset after this modification. I chose 2/16 toe-in.

PS3- Disclaimer. All info, including pictures, on this subject are for "educational purposes only". Performing this modification is at your own risk.