Question on Installing Original Datsun Competition Springs

[JLPurcell]

I pulled my original Datsun Competition Suspension out of my garage attic this week and plan to install it on my 72Z. It consist of springs, concentric s for the control arms and spacers for the front to correct the steering geometry. I took this off of the 70 race car years ago when we updated the suspension etc... I was looking at the Datsun Competition Parts Catalog for that period and it says that you must use struts #55302-E7213 and 55303-E7213. Dos anyone remember or know why. I currently have a new set of KYB's on the 72. Thanks in advance for the vast knowledge of this group. 

[DatsunZGuy]

This document denotes part numbers for left and right:

http://www.jdmjunkies.ch/wordpress/wp-content/uploads/2017/01/240Z-S30-factory-dampers-and-options-by-www.JDMjunkies.ch_.pdf

Right 55302-E7213 Left  55303-E7213

Edited February 20, 2017 by DatsunZGuy

[JLPurcell]

Front 54302-E7213 (R) 54303-E7213 (L)

Rear  55302-E7213 (R) 55303-E7213 (L)

I guess the real question is; Will I be able to put the springs on my stock struts with KYB inserts? The racing springs are much shorter than stock.

[HS30-H]

7 hours ago, JLPurcell said:

I was looking at the Datsun Competition Parts Catalog for that period and it says that you must use struts #55302-E7213 and 55303-E7213. Dos anyone remember or know why.

The E7211 springs are paired with the E7213 struts because the spring lengths are matched to the (fixed) spring platforms on the struts. If you try to fit the E7211 springs onto stock struts - especially north American market struts - the ride height and geometry will be wrong.

You could either cut and re-weld your spring platforms to suit the springs, or convert to adjustable platforms? The E7213 struts were hydraulic type and non-adjustable, so you can use any cartridge type insert that matches the springs.

[JLPurcell]

2 hours ago, HS30-H said:

The E7211 springs are paired with the E7213 struts because the spring lengths are matched to the (fixed) spring platforms on the struts. If you try to fit the E7211 springs onto stock struts - especially north American market struts - the ride height and geometry will be wrong.

You could either cut and re-weld your spring platforms to suit the springs, or convert to adjustable platforms? The E7213 struts were hydraulic type and non-adjustable, so you can use any cartridge type insert that matches the springs.

Alan, thanks you for the valuable information. As I stated there is a wealth of collective information on this site. I have the original set of race strut tubes for the rear. I will measure the height of the platforms and compare to stock rears on car. Now the issue is that the rears I have are hydraulic type. I am at a crossroad in this project, I will not cut on my original tubes so I would have to have a set of tubes for all 4 corners get the correct dimensions for the placement of the platforms and have them modified. I want it period correct and thus do not want to install adjustable platforms. This is obviously not a project that will be done for Z Attack, maybe s project for next winter. Does anyone have the specifications for the original Datsun Competition Strut tubes platform location? 

[JLPurcell]

Original Datsun Competition Parts List and Price List.

Datsun Competition parts list page 14.pdf

Price List page 22.pdf

[gnosez]

I might have a set (F/R) of the comp struts. If you can post the measurements I will check them when I get back home.

[JLPurcell]

6 hours ago, HS30-H said:

The E7211 springs are paired with the E7213 struts because the spring lengths are matched to the (fixed) spring platforms on the struts. If you try to fit the E7211 springs onto stock struts - especially north American market struts - the ride height and geometry will be wrong.

You could either cut and re-weld your spring platforms to suit the springs, or convert to adjustable platforms? The E7213 struts were hydraulic type and non-adjustable, so you can use any cartridge type insert that matches the springs.

Just measured the rear platform height on the old rear race suspension as compared to the stock rear on my 72 and the platform is at the same height relative to the top of the tube. I have attached a picture of the old rear suspension and the Datsun Competition Springs.  

[JLPurcell]

29 minutes ago, gnosez said:

I might have a set (F/R) of the comp struts. If you can post the measurements I will check them when I get back home.

I assume not something you would part with. Thanks for the offer. I am sure I will be needing some tech info before this project takes shape.

Thanks

[gnosez]

I got a complete set of 240 struts that I want to believe were shorter but had not been cut and welded, from a now retired racer along with a pile of other parts. Two of the shocks are stuck in the tubes and I had put them aside as I had no immediate need for them. Now I'm interested enough to take another look at them.

[CanTechZ]

Not exactly on topic but here is a great download (175mb) of a book printed in 1973 by Bill Fisher & Bob Waar, it's titled how to modify Datsun 510 610 240Z engines & Chassis.

http://datsun510.com/index.php?/files/file/138-how-to-modify-datsun-510-610-240z-engines-chassis/

Lots of great period stuff and some interesting 240z suspension mod info starting on page 212.

[HS30-H]

5 hours ago, JLPurcell said:

Just measured the rear platform height on the old rear race suspension as compared to the stock rear on my 72 and the platform is at the same height relative to the top of the tube. 

You would probably want to confirm that the total length of the strut tube (and therefore the distance from the spring platform to the hub) was the same as that on the E7213s. But if they are the same, then - surely? - you're good to go, no?