Z31 coilover setup question

[JimmyZ89]

I've done plenty of reading here so I figured I'd ask this here since you guys have a lot more suspension knowledge than most. I have an 89 Z31 2 seater that I want to upgrade my old and worn suspension to coilovers. I'm at a cross road as to which direction I want to take my suspension build. I have an extra set of z31 front and rear suspension parts and I also have the front spindles of a s14. Now before I get flamed with "your crazy you can't use s14 spindles" it has been done with success, here's a link the the post and writeup pdf:

http://www.z31performance.com/forum/viewtopic.php?f=2&t=3233&st=0&sk=t&sd=a

I've been in contact with this person and he has never had any issues with his swap and is very happy with it.

 

After reading the strut sticky I'm really interested in the koni 8611 but there is one problem, getting access to the bottom adj. knob. Unlike the older 240-280z's the z31 front strut tube is positioned directly on top of the ball joint. Now I did think of making a right angle worm gear contraption to act as a spacer under the insert allowing me access through the side of the strut for the bottom adj. knob, this is scenario #1. Scenario #2 is to use the s14 spindle and have some custom housings made for the 8611 insert like these http://nissanroadracing.com/vbulletin/showthread.php?t=128

This would allow access and the use of the 8611 insert in the front.

 

Now for the rear I can also go both ways, either koni da's or s13-14 coilovers. I'd prefer the da's. I did contact Jay at GC and he said that he can hook me up with the entire set up with koni doubles but I'll still have the issue with the front not having access to the bottom. Not having driven in a car with either of the shelf s13-14 coilovers or custom koni/gc setup I have to kind of rely of feed back from people that have. Unfortuntely for me every one has an opinion. My intensions for my Z is to keep it as my daily driver and use it for weekend events. I've always wanted to get into road racing and I have played in drag racing in the past, test and tune times at the track nothing pro.

 

thanks

 

Jimmie

[260DET]

The Koni 8611 insert has a slotted (screwdriver) adjuster in the bottom of it from memory, no knob. So its too fat to fit inside the stock S13 or 14 housing?

 

I'm not sure what your main question is, are you asking whether the Z31 or S13/14 setup is the best? If so I'd go with the S setup in which case there are a huge number of choices as to the various components, without the need for any custom made bits that adapting Konis may require.

 

Koni make good stuff but then so do others.

[OK85ZX]

The 8611 isn't a coilover, it's just a strut cartridge.. like an illumina/bilstein/etc.. Your best bet for useing full coilovers is to go with the weld on collars for the front knuckles as shown on that same board (z31performance.com) since that S14 swap has yet to be put through any punishment by that user, and the people who have punished them have found bad weak spots. 2 weld on collars and you can use a complete coilover kit for an S13.

 

If all you plan on doing is keeping it as a daily driver and just doing misc weekend warrior activities, I would just go with a set of adjustable tokico's and some higher springrate springs (such as Z3R or ST for a little softer.)

[JimmyZ89]

OK85ZX I know that the 8611 isn't a coilover and only a strut insert. If I were to use the 8611 I would use it with ground control coilover sleeves and make my own coilovers. As far as the adjustable tokico and ST springs(still to soft) and Z3R springs (better but still not to my wants/needs) that combo is just not for me. Zmech, the person that did that s14 coilover mod, has tracked the car and was pretty satisfied from our conversations. It's just personal preference and yes I've been in a Z with the tockico illuminas and st springs and I still didn't like them.

 

260DET yeah I guess I didn't really post this in a question format. Ok so here goes. For those of your that may have used both, How does the 8611/10 insert compare to off the shelf s13 coilovers?

[zmech]

Your best bet for useing full coilovers is to go with the weld on collars for the front knuckles as shown on that same board (z31performance.com) since that S14 swap has yet to be put through any punishment by that user, and the people who have punished them have found bad weak spots.

 

HUH?

Just wondering what weakness you are talking about because I have done my fair share of punishing to that suspension. I may not run the tracks as much as some because of funding, home mortgage makes it like that in California.

Back to suspension though. What weakness??? I have taken my car to multiple autocross, three times at Willow Springs big track and once at Laguna. So if you mean drifting as punishment, that is something that I do not do.

 

[johnc]

The 240Z also positions the bottom of the front strut tube over the ball joint. Its very similar to the Z31 front strut setup.

 

Having run the 8611s on a S30 it takes the removal of four bolts and one anti-roll bar end link to get at the compression adjuster on the front 8611s. Its not something that has to be done very often and I am able to do in 15 minutes on the front of an S30.

 

The rebound adjustment is normally used more often then compression when tailoring a car to a specific track. Compression gives the base platform (almost like spring rate) and then rebound is used to control the sprung mass.

 

I did build a geared adjuster for the 8611 once and it wasn't worth the expense and effort IMHO. The customer liked it, used it once or twice, and then left the compression adjuster at 3 for the next two years.

 

Measure the ID of the strut tubes to make sure the 8611 will fit. The OD of the 8611 shock body is 1.71".