Jason Gray's 280zx Strut Writeup
Adding 280zx sruts and brakes to a 510 requires removing the large diameter 280zx spring perch. The smaller stock 510 spring perch is then welded in place on the 280zx strut. Alternativly, expensive aftermarket threaded collars are attached to the strut tube for use with small diameter coil-over springs and adjustable ride height. The steps required for a 280zx strut swap are well documented in Dime Quarterly volume 2 issue 4. Get a copy of the complete article if you plan to do a 280zx brake swap An online sample is found at http://dimequarterly.tierranet.com/articles/tech_280ZX_brakes.html.
I could not justify the cost of small diameter coil-over threaded adjustment conversion for my streetgoing 510. Besides, Ive found that you cannot simply adjust the ride height independantly of the other suspension settings. Camber is effected by ride height and toe-in effected by camber. So, you cannot simply adjust your ride height from day to day without doing a complete front end alignment each time.
I didnt like the idea of simply welding the 510 spring perch onto the 280zx strut tube. Welding makes for a rather non-adjustable instalation. I wanted some ride height adjustment ability. What I have devised is an inexpensive method of providing ride heigh adjustment, altho without the convenience of threaded coil-overs.
I searched a hardware store and found some 2" inside diameter steel pipe, (1/8" wall thickness). 2" ID pipe will slip over the 280zx strut tube with minimal clearance. I cut the pipe into several 2" lengths. I welded one of the rings to the center of the strut tube and welded another ring to the bottom of the spring perch. (in the photo below, my spring perch is not the original 510 perch but the 510 perch would work just as well). Another piece of pipe serves as the adjustment spacer between between the ring welded to the strut and the ring welded to the perch. I made up several sets of adjsutment spacers in slightly different lengths, by changing out the adjustment spacer I am able to raise or lower the height of the spring perch. This allows the spring perch to be setup as low and close to the tire as I care to set it. If a taller front ride height is desired or larger diameter tires are mounted, just dissasemble the strut and install a taller spacer ring to raise ride height and provide additional clearance as needed. Not as convenient as threaded collars but it shure beats grinding off the solidly welded on perch and re-welding to achieve height difference!
Dissasembled strut. One ring is welded to strut (height near top of disk), the loose ring serves as the height adjustment spacer and the top ring is welded directly to the spring perch.
Love the stopping power of those big ventilated 280zx disks!
An alternative method (no welding and easier height adjustment) for setting the spring perch was shared by Jerry Cox:
"This is going to sound a little cheap, but I use two muffler clamp saddles, trash the U-bolts and use 2 bolts, 2 nuts and 2 lockwashers along with the two muffler clamp saddles under the spring perch. I've used this for 8 years on my ITC 510 with out a single problem. I've also use it on my son's 510 which is a daily driver that's got ZX struts. " - Jerry