How much damping oil for 280zx stock strut shock?

[78dattysun]

Doing 280zx coil overs for my 510 an have 20w fork oil. How much oil is recommended for each strut or what do you guys recommend?

 

I seen datsun mike post once that recommend was about 325 cc an he used about 2/3 of a liter for both. Seems fine to me just don't know if a little changes alot. Thanks

[flatcat19]

I would think you want it full.

 

What is a CC?

Flippin' metric system.

[78dattysun]

Ha ya its cubic centimeters. 1000cc is one liter. Nobody?

[datzenmike]

Just fill to 1/4" from top to allow for any heat expansion of the oil. A one liter container will easily do two struts. It's around 330cc so you could do three of them.

 

Be sure to extend fully and compress. Then turn upside down and extend and compress to expel any air from the valves. Check the level once more and seal them up.

 

I'm running 20W on 150 lb/in springs and it's firmer than stock for sure. Now 510 racers go 300 and above, street cars 250-275 lb/in but is this just hubris? I don't race and I don't want a tank's suspension. Would you need thicker stiffer shocks with a stiffer spring? Would think so, but who knows? Simply saying:  'my tokikos strut inserts are great with my X spring rate' doesn't mean much to me. Some day I'll swap my Maxima struts side to side to move the calipers forward out of the way of the steering... when I do I may try trimming the spring to 175 or 200 because I have a spare set. Will have to find out more about the damping vs. spring rate first though. For now 150 and 20W is fine for the driving I do which is to Canby and maybe a tank full around town only in the summer for less than three months.

[banzai510(hainz)]

could buy these

http://classicgarage.com/28in22andtur.html

[78dattysun]

Ya I could but I'm cheap lol. And the stock shocks will work just as good in my opinion. Thanks for the link tho!

 

I don't know my spring weight but found a set of coil over kit on a Honda civic an fits perfect on the datsun struts. I figure it's spring rates are comparable considering the cars weigh about the same. So figure it will work fine with 20w shocks.

 

But thank you! That should be all the info I need.

[datzenmike]

The spring rate can be worked out with three simple measurements. (not you) but I can't believe the number of people that buy coils with no idea what the rate is. Almost for sure it will be too soft or too stiff for them but they don't know better and think this is great. It's very unlikely you will get what suits you and most likely it will take several trys to get that 'sweet ride' you want.

 

I got a set of coil overs near me from a guywho wanted to getrtid of. I worked the rate out to 500 lbs/in!!!!!!! WTF?

[78dattysun]

Ha ya I know what your saying an I'm kinda part of the group just cuz I don't know what the rate is an I just said screw it an gonna try it out but I figured that it may take a few try a to get the ride quality I'm looking for. Plus I only paid $20 for them both. I think I will try an figure out my spring rate tho so I know what all I'm dealing with before I just throw them under there.

But 500lbs is crazy.

What is stock 280zx spring rate? The coil over spring I have feels just a bit stiffer that the stock 280zx ones.

[78dattysun]

Also datzenmike when you day 1/4" full of oil is that from the top of the strut housing with shock inside? Or qtr way full from the shock when inside?

[datzenmike]

That's with the damper installed in the strut tube. Just pour the oil in and leave some space. Don't forget that O ring and then tighten the gland nut down. Bleed as described and take the gland nut off and take a look. The level may have dropped if an air bubble was burped out.

 

I'm running Maxima struts and brakes. The Maxima is built on the zx platform so very similar parts. I worked out the spring rate for it and it's 150 lb/in. I can assume the zx is about the same weight as the Maxima. So I dialed in 150 on my 710 springs and that's 50% more than stock. I now know what 150 feels like.

[78dattysun]

Ha that's funny. You just can man handle a spring an be like (that's a 150) lol awesome.

 

But cool I thank you again very much an once I get it all under the car I'll post some pics hopefully.

 

Having a buddy a machine shop make me some TC rods an mod my front control arms for adjustment on both. Also making a steering box brace an some simple idler arm braces. All be painted to match with a metallic dark Grey an all new red poly bushing an a moog steering kit. Also have a 1" racing sway bar for 510. This all going on a wagon.

The thing has a built motor but steers an stops like shit so now it should be a fun little wagon.

[78dattysun]

Also I can't seem to find how to post pics. It's been so long I can't find the forum an photo bucket had changed an is all diff now an can't figure it out. One ya guys mind showing me the link on how to lol. As much yall hate to an for me to sound like a noob lol

[LenRobertson]

78dattysun - I wanted to thank you for posting this question and following up to get all the details. I need to do the ZX struts I got for my 510 and was kind of hazy on how full is full in the strut tube.

 

As to posting pics, click on "More Reply Options" at the bottom of the page. Then above the box where you type your reply text are 2 rows of icons. About half way across the lower row is one that will say "Image" when you move your cursor across it. Left click on this and a box will pop up where you paste the URL of your pic from Photo Bucket or whatever pic host you use. But I can't tell you exactly how to find the URL on your hosting site. I know for Flickr it is sometimes tricky to find the correct URL that will work on Ratsun. Flickr seems to pay a bunch of programers to constantly "improve" the site. Which means "screw it all up for the user". Maybe Photo Bucket URLs are easy to find.

 

Len

[78dattysun]

No problem Len. Glad my question helps for more than just me. And thank you very much for helping me with the pic thing.

 

 

OK I filled the struts up with roughly 330 cc an it's not exactly 1/4" from the top because it fills part of the damper tube as well as the strut tube. But it feels fine just want to get this right the first time. I'll try and get some pics on here to help see the big picture.

[78dattysun]

[78dattysun]

OK so here it is with the damping tube and the damping rod in it too. The level is fairly high in the damping tube but not as much around it in the strut tube.

 

[78dattysun]

And here it is when the damping rod is out but damping tube is still in the strut tube. And this is roughly 330 cc of damping oil. And it's 15w not 20w. But hoping it will do the trick.

 

[78dattysun]

Also now my gland nut won't thread down all the way. I'm guessing it's suppose to be at this height because they are both stopping here an there are 2 gaps in the top of the gland nut that draws in the air? Maybe lol. Anybody know If this looks correct?

 

[78dattysun]