options for front springs on a 510.

[Datsweet]

so im going to run the 280zx front shock on my 510.  im going to cut off the collar off and use that adjustable collar thing.

 

my question is are there any good stock springs that fits the 510 that provides a stiff feel or should i just get some eibachs?

 

[datzenmike]

This is too easy. One of the properties of a coil spring is that when you trim it, it gets stiffer. I know, sounds backwards but there are formulae for working out the spring rates so you can know what you are getting before you cut. My 710 spring was about 100 lb per inch and I cut around 1.5 coils  off to get 150. The 510 spring is 89 lb/in. If you make a few simple but careful measurements on your stock spring I can work out how much to trim it to get what you want. I went with 150 although many might find this too soft. Many 510s are run between 175 and 225 lb/in. Track 510s can exceed 300 lb/in. Take care as, once cut you find it objectionably too stiff a ride, you can't go back.  All you need is a hand held 6" angle grinder and a metal cutting blade about $3.50 to make this happen. 

 

One other thing while you have the zx strut apart.

 

If the insides have never been replaced with a replaceable shock insert and still have the stock valves, you can substitute the thin watery hydraulic oil with thicker motorcycle fork oil. The thicker oil is harder to push through the valves and increases the resistance and damping. This is what I did. I used 20W Belray shock oil and one liter was $17 and enough for three struts. It's also full of rust inhibiters and anti foaming agents.

[Rob_the_Goonster]

ok so i just want to know for sure in plain simpleness haha,  can you or can you not rebuild the stock 510 shock/strut for the front end?(such as valving and oil change?)

[datzenmike]

Yes you can....... BUT.

If a previous owner has already removed the stock strut internals and replaced them with sealed shock inserts then no.


Stock strut internals will look like this...
 

 

[Rob_the_Goonster]

ok so that insert is not welded to the spindle body right? or did i run across some shady parts?? 

[datzenmike]

It's removable and comes apart as shown above. It sits in an oil bath inside the strut tube.

 

 

This is a self contained insert for a 240Z car and you remove them and throw away when worn out. At $160 each that's robbery. Maybe I'm just too cheap but $17 for thicker fluid that more or less does the same job appeals to my Scottish ancestry. :lol:

 

[Rob_the_Goonster]

haha no that makes total sense to me to use or AT LEAST TRY the thicker oil!! 

thanks King Rat! huge help bud!! :D

totally not sarcasm btw haha^^^ 

[datzenmike]

Only works if you have the original strut dampers.