280ZX rear strut & 300ZX front strut J30 options

General discussion forum for J30 and M30 owners!
jester4666
Posts: 113
Joined: Sat Jul 28, 2012 10:46 pm
Car: 1994 Infiniti J30t

Post

thank you for the clarification. i know i sound like a pain, but i don't have extra money to just throw at parts...so i ask lots of questions before i make any purchases.


J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

I understand there are inserts to take the place of the original piston/oil filled/non-pressurized strut tube configuration, what I have is still stock and in decent condition but for racing they are a bit under dampened, what I am hoping to do is disassemble, measure and replace the thin shock oil for something thicker, not only is this the legal way to modify a shock in this series but it is also the cheapest.

User avatar
Mkiisupra
Posts: 129
Joined: Thu Jan 17, 2008 10:19 pm
Location: Fresno Ca

Post

I just ordered new kyb struts and shocks all around. I was hoping to get some better information regarding the bronze sleeve bushings to keep the shaft centered but it seems neither of the 2 members who used the same struts I ordered post here anymore. I suppose I will just figure it out when Im ready to install them. I post a guide when I start the process just to cover anything that may have been left out by other members. I also ordered the pair of energy suspension front tension rod bushings and will do my best to document that installation as well.

Thanks to the research that went into this we can all have much better handling J's without having to buy ots oem replacements that may not work anyway.

User avatar
yodawill2000
Posts: 3888
Joined: Thu Mar 24, 2005 4:10 pm
Car: 94 Infiniti J30
Location: Grand Prairie TEXAS

Post

A well documented "How Too" for all 4 corners should definitely be a Sticky here ! :dblthumb:
The rears are quite simple bolt on's, but the fronts take some doing.

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

I am looking for stiffer stockish springs for the front (think z31 300z turbo) but am unsure of the factory rate we already have.
Anyone have ideas, ride quality is no concern.

User avatar
jdurrty
Posts: 158
Joined: Thu Nov 19, 2009 7:10 pm
Car: j30

Post

Yoda-
I'm going to be re-doing the front struts with correctly-fitting, metal bushings instead of the improvised plastic ones and also replacing all the rubber bushings with new energy suspension ones. I will take as many pictures and documentation as I can if you can wait until the end of this semester when I finally have some free time.

User avatar
Mkiisupra
Posts: 129
Joined: Thu Jan 17, 2008 10:19 pm
Location: Fresno Ca

Post

J30tChumpCar wrote:I am looking for stiffer stockish springs for the front (think z31 300z turbo) but am unsure of the factory rate we already have.
Anyone have ideas, ride quality is no concern.
Eibach makes custom springs, you just need to provide them with the spring rate and dimensions you want.

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

I like the idea but this race series frowns on new custom springs.
Z21 springs fit our cars but before I shop I was wondering if anyone has measured what spring rate a J30 came with.
A chart
http://www.az-zbum.com/information.springs.shtml

User avatar
Mkiisupra
Posts: 129
Joined: Thu Jan 17, 2008 10:19 pm
Location: Fresno Ca

Post

Nothing for a z31 would be a close enough spring rate to be worth buying and would also lower the car too much. Custom springs are the only way to go.

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

Still looking for something, from another model, not custom, amount of lowering is no problem I already run stock springs cut 2.5 coils

User avatar
nemo44
Posts: 26
Joined: Fri Mar 16, 2012 12:48 am
Car: 1993 infiniti j30
Location: Somerton, Az

Post

What mods did you have to make to the KYB? if any?

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

nemo44 wrote:What mods did you have to make to the KYB? if any?
For the rear? No mods at all.

User avatar
nemo44
Posts: 26
Joined: Fri Mar 16, 2012 12:48 am
Car: 1993 infiniti j30
Location: Somerton, Az

Post

oh ok nice :) ill be trying it out next week then see how it goes :D

User avatar
Mkiisupra
Posts: 129
Joined: Thu Jan 17, 2008 10:19 pm
Location: Fresno Ca

Post

I just did the rears on mine today. The spring seat looks a little small for the J30 spring but it just barely fits.

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

Had a issue with the front struts after the last event, they were loose on compression, normal on rebound, no leakage or binding so we took them apart, a very simple task once they are off the car and springless. First the fluid was drained and measured, then inspection reviled the lower valve was unscrewing itself , thread locker applied, new motorcycle fork oil. Next event is early December, will update success or failure.

User avatar
yodawill2000
Posts: 3888
Joined: Thu Mar 24, 2005 4:10 pm
Car: 94 Infiniti J30
Location: Grand Prairie TEXAS

Post

A how too on that move would be great !!
Mine don't leak either but I'm sure they could use a rehab.

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

I didn't take pics but its sooo simple when time permits I will pull apart a spare strut to do a quickie how to.

purnellusa
Posts: 6
Joined: Sun Apr 13, 2014 5:55 am
Car: 1993 Infiniti J30

Post

J30in the sun – were these the only two modifications you had to do for the front strut installation for the KYB's? The retaining nut on the strut cartridge and the insert between the threads and upper mount bearing? Some other members are talking about the length and OD of the cartridge being an issue.
Thanks,
Doug

kgzzy
Posts: 3
Joined: Tue May 13, 2014 9:56 am
Car: 1994 infiniti j30

Post

Jdrrty... What struts did you end up going with for the front and rear strut replacements. i see the one for the rear did you use monroe or kyb? what about the front??? i dont have any tool for modding so i need something that will just fit right like the rears?

camn
Posts: 17
Joined: Thu Aug 01, 2013 12:39 pm
Car: '01 Path
'09 g37

Post

At minimum you need a dremel tool.
Which is cheap.
And easy to use.
And useful in a 1000 other ways :)

User avatar
J30inthe sun
Posts: 246
Joined: Wed Mar 07, 2007 4:48 am
Car: 1997 J30

Post

kgzzy wrote:Jdrrty... What struts did you end up going with for the front and rear strut replacements. i see the one for the rear did you use monroe or kyb? what about the front??? i dont have any tool for modding so i need something that will just fit right like the rears?
The only exact replacement for the front struts WITHOUT any modding are the replacements from Infiniti.

kgzzy
Posts: 3
Joined: Tue May 13, 2014 9:56 am
Car: 1994 infiniti j30

Post

What difference will it make if i go factor struts for front and 280zx stuts for rear?
Do you think it will be any lol height difference?

User avatar
J30inthe sun
Posts: 246
Joined: Wed Mar 07, 2007 4:48 am
Car: 1997 J30

Post

kgzzy wrote:What difference will it make if i go factor struts for front and 280zx stuts for rear?
Do you think it will be any lol height difference?
There should be no difference in ride height. The cars springs determine ride height.

I would not use factory front struts, they have probably been sitting on a shelf for at least 10 years. When I bought factory struts inserts in 2009 from Infiniti of Scottsdale they lasted less than 40,000 miles. You are better off finding a shop that will mod the top strut tube retaining nut & then using 300ZX strut inserts. The cost if the addition labor for this install should 've the difference you will pay for factory inserts. Then you will have a better quality strut that should last longer. Its a win-wings situation.

Do you want to pay the same price for front struts that may only last for 20-30k miles or do you want a quality struts that will last 50k+ with the ability to have them serviced easily in the future?

^^I opted for the latter.

User avatar
J30inthe sun
Posts: 246
Joined: Wed Mar 07, 2007 4:48 am
Car: 1997 J30

Post

^^Dang auto-correct

camn
Posts: 17
Joined: Thu Aug 01, 2013 12:39 pm
Car: '01 Path
'09 g37

Post

You can do it, kgzzy!
Get a dremel! They are cheap!

The hardest part of the job is compressing the springs!

We believe in you!

J30tChumpCar
Posts: 487
Joined: Sat Jan 23, 2010 1:34 pm
Car: 1995 J30t Totaled @ Charlotte motor speedway
1994 J30 gutted caged road racer Now with VH45DE!
1966 Chevy Corvair V8 mid-ship conversion
Location: WPB Fl.
Contact:

Post

Thread from the dead...

Following up on the previously mentioned front strut oil change and KYB rear struts from Rock Auto

Just now have we lost a rear strut, the RR blew out after 15,000 miles of full out racing, I will look into rock autos warranty, if there is no coverage the same will be bought to replace... Happy KYB customer...

Front struts feel great with 15w motorcycle oil, the failure point is always the top cap seal,completely unavailable new, I scour the junkyards for sub 150,000mile cars with dry struts to harvest the top cap.

User avatar
roasawyer
Posts: 5
Joined: Fri Mar 20, 2020 6:15 am
Car: Infiniti J30t

Post

try this to the front , you will have more fun adapting the 300zx cart to the mount.
Attachments
IMG_20200127_170306.jpg

User avatar
Niti QX4
Posts: 173
Joined: Sun Apr 16, 2017 6:45 am
Car: 2004 Nissan Xterra

Post

Very Nice!!. Did you make those or did you find a place that has them for sale?

Oh, and if you made them - are they steel or aluminum?

User avatar
roasawyer
Posts: 5
Joined: Fri Mar 20, 2020 6:15 am
Car: Infiniti J30t

Post

they are cut from the top of the old cartridge, drilled,with end mill, tapped to match the new chosen shock, all
but five threads were cut off of the new (kyb) cartridge. the old retaining nut was modified to fit around the new cart and the floor of the nut was increased for more thread engagement, if you just widen the nut you will only get 1.5 thread, didnt seem enough to me so floor/ceiling whatever was increased, in other words once the dia is chosen plundge the tool a little for more thread engagement, careful dont plundge to deep or the nut wont retain anything and cart will rattle. Thanks glad you liked it.


Return to “J30 Forum / M30 Forum”