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Strut Sectioning FAQ


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#21 JMortensen

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Posted 02 May 2011 - 12:41 PM

Be careful sectioning too much and/or lowering your car too far. You eventually get into a situation where suspension hits frame, tie rods bottom out, etc. I can't tell you where exactly those problems happen, but I can tell you that with stock rear control arms and normally sectioned struts I was able to hit the rear frame with the control arm. You could put a longer bumpstop in there to prevent metal to metal contact if there is any. In the front with rod end sway bar end links I had to try 2 or 3 times to set them up so that they didn't bind up as well. If this stuff binds on a big bump something could bend or break, not a good thing.

Bumpsteer also gets pretty nasty when the car is super low, and bumpsteer spacers don't fix bump steer. Read the bumpsteer FAQ for more on that if you're going to go really low.

Jon Mortensen, owner/operator www.petdoorstore.com


#22 MikeyM

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Posted 02 May 2011 - 12:50 PM

Be careful sectioning too much and/or lowering your car too far. You eventually get into a situation where suspension hits frame, tie rods bottom out, etc. I can't tell you where exactly those problems happen, but I can tell you that with stock rear control arms and normally sectioned struts I was able to hit the rear frame with the control arm. You could put a longer bumpstop in there to prevent metal to metal contact if there is any. In the front with rod end sway bar end links I had to try 2 or 3 times to set them up so that they didn't bind up as well. If this stuff binds on a big bump something could bend or break, not a good thing.

Bumpsteer also gets pretty nasty when the car is super low, and bumpsteer spacers don't fix bump steer. Read the bumpsteer FAQ for more on that if you're going to go really low.



Thanks. I'm not actually planning on going super low, but I'd like to go lower than most. Just trying to understand the limitations of the 1437's in terms of ride height. For example, can you get to the suspension-hit-frame senario with the 1437's or do you need the 1436's to get to that point?

#23 MikeyM

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Posted 02 May 2011 - 01:00 PM

Be careful sectioning too much and/or lowering your car too far. You eventually get into a situation where suspension hits frame, tie rods bottom out, etc. I can't tell you where exactly those problems happen, but I can tell you that with stock rear control arms and normally sectioned struts I was able to hit the rear frame with the control arm. You could put a longer bumpstop in there to prevent metal to metal contact if there is any. In the front with rod end sway bar end links I had to try 2 or 3 times to set them up so that they didn't bind up as well. If this stuff binds on a big bump something could bend or break, not a good thing.

Bumpsteer also gets pretty nasty when the car is super low, and bumpsteer spacers don't fix bump steer. Read the bumpsteer FAQ for more on that if you're going to go really low.



Thanks. I'm not actually planning on going super low, but I'd like to go lower than most. Just trying to understand the limitations of the 1437's in terms of ride height. For example, can you get to the suspension-hit-frame senario with the 1437's or do you need the 1436's to get to that point?

#24 JMortensen

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Posted 02 May 2011 - 02:17 PM

Depends. You really would need to section to the shorter strut and then add in bump stop length until you could have the travel you want without any binding. To check for binding you need to remove the spring and the sway bar from the opposite side, and then move the suspension through its range of motion BY HAND. If you do it with a floor jack there's a good chance of missing the bind completely.

The risk in this is that if you section too short you might not have enough droop when you're done.

Jon Mortensen, owner/operator www.petdoorstore.com


#25 MikeyM

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Posted 02 May 2011 - 02:24 PM

In your opinion, does the 1437 practically limit the amount you can lower your car? Or is it a non-issue?

#26 JMortensen

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Posted 02 May 2011 - 02:49 PM

I don't know the specs on that strut. Coffey would be better able to answer that question.

Jon Mortensen, owner/operator www.petdoorstore.com


#27 johnc

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Posted 05 May 2011 - 07:28 AM

In your opinion, does the 1437 practically limit the amount you can lower your car? Or is it a non-issue?


No. The practical limit is determined by the suspension mounting points and where the roll centers end up. In general, on 14" wheels, you can't go lower then 5" measured at the rocker panel without changing the inner mounting points of the front lower control arms. On 15" wheels you're limited to about 5 1/2", 16" wheels about 6", etc.

This practical limit is for a good handling S30. If you don't care about handling then you can go much lower, but then why would you be looking at installing the Konis if you don't care about handling?
----- John Coffey, Fabricator at Benton Performance, LLC

#28 MikeyM

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Posted 05 May 2011 - 08:28 PM

Cool, Thanks for confirming that JohnC.

You're correct, I do want good handling. And wanted to get the best shocks I could that would suit the track without going totally overboard price wise.

I dont want to go lower than what is beneficial, so it's good to confirm the 8610-1437's will go a low as I'll ever need.

I've put in my order for them and GC coil-overs & camber plates. Woohoo!

#29 CarolinaTZ

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Posted 06 April 2012 - 05:31 PM

Hey guys, I'm in the process of completely replacing/rebuilding the suspension on my 72 240Z and have read most all the threads and sticky's about this on here. Urethane bushings, sectioned struts w/ Illuminas, 5" threaded collars, 10" springs 225F/250R. Oh, by the way I'm doing this w/ a complete suspension from a 77 280Z. I understand this will bolt in but it also leads me to a couple of questions. This will be mainly a street car w/ maybe some track time. Using 16" wheels w/ a planned ride height of 6" but with the ability to go a little lower if I so choose.

So, here is my 1st question: Although they are 280Z struts, on the front should I still use the 240Z recommended inside tube height of 13.375" - 13.500" and a perch height of 5.25"? Same question for the rear. Should I achieve an inside tube height of 14.938" - 15.000" and a perch height of 7.25"? If I understand correctly, although they are 280Z struts (the rear 280Z struts are a couple of inches longer than 240Z rear struts), if I use the dimensions posted byjohnc, I will essentially have what is dimensionally identical to 240Z sectioned struts. Can anyone confirm or correct me if I'm wrong.

My second question is: Should I use the rear 240Z strut tops instead of the taller 280Z rear strut tops, if the 280Z struts are going into a 240Z?

I hope this makes since and someone will confirm or correct. Thanks in advance.

#30 johnc

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Posted 07 April 2012 - 07:18 AM

Since you are putting a 280Z suspension into a 240Z then you should use the 240Z strut tube measurements and the 240Z upper insulators.
----- John Coffey, Fabricator at Benton Performance, LLC

#31 CarolinaTZ

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Posted 08 April 2012 - 06:53 PM

Thanks a lot johnc! That's what I was thinking...basically treat the 280Z struts as if they were 240Z struts.

Will this perch measurement allow me to run approx. 6" ride height and be able to go up or down an inch or so?

#32 Jasonmreiss

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Posted 20 October 2012 - 01:26 PM

Ok I think I am confused. I am doing this on a 280, I have the 12" springs and 4" collars from ground control. Using illuminas. Will the same measurements from the 240 work? As in final length of strut tube, and where to weld the lower ring.

I'm using the bz3099 in front and bz3013 in back, I'd like the car to drop 2-3 ", I'll be using stock insulators. Thanks and sorry if this has been covered. I did read extensively but just couldn't find exact measurements for the 280

#33 johnc

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Posted 22 October 2012 - 08:07 AM

Ok I think I am confused. I am doing this on a 280, I have the 12" springs and 4" collars from ground control. Using illuminas. Will the same measurements from the 240 work? As in final length of strut tube, and where to weld the lower ring.


Since the FAQ uses 10" tall springs and 5" tall collars, you need to do some math to figure out what will work for you.

I'm using the bz3099 in front and bz3013 in back, I'd like the car to drop 2-3 ", I'll be using stock insulators. Thanks and sorry if this has been covered. I did read extensively but just couldn't find exact measurements for the 280


For a 280Z I suggest you shorten the front struts for the BZ3099s to fit without a spacer in the bottom and take note of how much you remove from the strut tube. Remove the exact same amount from the rear strut tube and make a correct length spacer to fit the BZ3013.
----- John Coffey, Fabricator at Benton Performance, LLC

#34 cockerstar

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Posted 22 October 2012 - 09:05 AM

You need to be using the BZ30b[]12[/b] strut in the rear, not the BZ3013.

I remember reading that the 3012 is just a 3013 with a spacer welded to the bottom of that, so you may be able to conceivably remove it and run it. A BZ3013 strut will not fit in a shortened hosing.
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#35 rhettro74

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Posted 17 October 2013 - 01:51 PM

For a 280Z I suggest you shorten the front struts for the BZ3099s to fit without a spacer in the bottom and take note of how much you remove from the strut tube. Remove the exact same amount from the rear strut tube and make a correct length spacer to fit the BZ3013.

 

I am about to start sectioning struts and building coilovers using Bilstein p30-0032 on a 77 280z however if I cut my front tubes to fit the Bilstein inserts as suggested above for the illuminas I would be shortening my tubes by 2.25 inches. The DIY on doing the Bilsteins target is 1.5 inch but then use a 9/16" spacer at the bottom of the tube. I would rather not use a spacer on the fronts if possible but I understand that sectioning more than 2" is a bad Idea. Should I stay with the 1.5" with these inserts? Planning on running Group buy 17" Rota RB-r's 


Edited by rhettro74, 18 October 2013 - 06:50 AM.


#36 Bob-omb

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Posted 21 December 2014 - 07:17 PM

Johnc, I think you may have the wrong part number listed for the 280Z Koni gland nut.

 

http://forums.hybrid...land-nut-loose/


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#37 johnc

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Posted 22 December 2014 - 08:35 AM

Could be.  Koni and Bilstein also changed some of their part numbers back in 2008.


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#38 Bob-omb

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Posted 22 December 2014 - 11:48 AM

The correct part for the 280Z nut is:  73.25.00.025.1 (M52 x 1.5p)

 

I don't think the number changed.  Looks like 73.25.00.007.1 (M51 x 1.5p) was never the right part.


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#39 konradlip

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Posted 01 April 2015 - 04:08 PM

So I cant find anywhere what struts to use for sectioning on a 280z. I have 10 inch GC coilovers and i will probably just go with KYB stockish shocks. can someone please help. right now the Z is sitting higher than my outback and i hate positive camber. thanks



#40 johnc

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Posted 01 April 2015 - 07:13 PM

Really? You've read through this whole thread and can't figure out what shocks to put on your 280z strut tubes?
----- John Coffey, Fabricator at Benton Performance, LLC




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