NS F355 Project (Page 48/73)
Yarmouth Fiero SEP 19, 08:06 AM
It's a Canadian thing to do Bob
Yarmouth Fiero SEP 25, 09:28 PM
With the arrival of the QA1 rear coilover struts, I've proceeded to add them to my 3D model to confirm the geometry will work as expected.

Here are a few pictures of the strut in location on the spindle. In these drawings the strut is at full extension. With the 325 lb springs, I expect the struts to compress about 2 1/2" atleast. That should make them the perfect length for this installation. I've also added a few pictures showing the new strut location in relation to the stock strut tower. As shown, the strut has been moved outward 4" to match the new rear track width of the 355. However, it is quite close to the inner edge of the upper frame rail so I may either notch the frame rail or use an offset spacer on the spindle to locate the strut inward about 1 1/2" to give lots of clearance.
355Fiero SEP 26, 04:50 PM
Graham;

You have already probably done this but I would set the ride height you want first in the model and then set up the tower to best position the strut for middle of the shaft in loaded rest.

I ended up with pretty short compression strut travel on mine when I was trying to pull the frame/body down to sit properly over the wheels. My mistake was not looking at ride height first and as a result was going to to need to redo some of the wheel arches and/or frame mounting points to get some ride height back and still have the panels far enough down to not look like a 4x4....... I find all replica 355 panels are like that so start with ride height and work your way up from there.

Cheers
Don
Yarmouth Fiero SEP 26, 05:39 PM
Thanks Don. I have my actual car chassis set at the same ride height as Blooze and my model is drawn the same. I can easily compress the spring in my 3D model to the height I need to suit the final ride height. I"ll add those drawings tonight.
Yarmouth Fiero SEP 27, 03:39 PM
I have been working on my new strut tower design to incorporate the QA1 coilover struts I purchased. As I had mentioned, I considered moving the strut outward a portion of the 4" needed per side and using an offset bracket between the lower end of the strut and the spindle to make up the remaining distance. By doing this, I could lower the end of the strut downward with the bracket in an effort to gain a little more travel in the strut. Well, I suspected the lower end of the new strut would be close to the drive shaft so I added the CV boot to my drawing just to see how close. Ouch. They are going to be within 1/8" of each other.



I was currious why so I dug out the stock strut from under the workbench and compared it to the new QA1 strut. Its quite clear to me now. The adjustment section on the lower end of the QA1 strut makes it quite a bit longer. Because of this, my relocation bracket for my strut/ spindle connection may have to incorporate some lift to the strut......... just the opposite to what I wanted. Here are a couple pictures of the two struts side by side.





Back to the drawing board.
Bloozberry SEP 27, 05:41 PM
Well that sucks.
Yarmouth Fiero SEP 27, 10:02 PM

quote
Originally posted by Bloozberry:

Well that sucks.



Thanks for the input Blooz. Is this your professional opinion of my situation?

I've been scouring your thread tonight re-reading all your rear suspension details and there is a nice rear view drawing on page 16 about 2/3 down the page that does show that the shaft angle should move down and away from the strut, atleast in jounce. It may be an issue during rebound though. The more I read, the more I realize that the position and angle of my strut as well as the length and angle of the control arm is going to critical so that this arrangement doesn't bind or exceed the limits of the ball joint and upper strut bearing. I'll have to make sure this design works before I start cutting steel and fabricating.

Looking more closely at the the stock strut, it appears from the lower two mounting bolt holes are on an axis about 5 degrees off the strut body axis where as my QA1 struts have the holes on the same axis as the strut body. I may be able to incorporate this extra 5 degrees in my strut/ spindle adapter bracket as it helps move the bottom of the strut a little further away from the CV boot.





Edit: to add drawings

[This message has been edited by Yarmouth Fiero (edited 09-27-2014).]

fieroguru SEP 27, 10:39 PM
You might look into a different style CV boot.

There are some where the largest part (OD) is where it clamps to the CV housing vs. it being 3/4" or larger than the clamp OD due to the V shaped accordion grooves. Past the CV housing, its just the axle shaft, so the boot can be much smaller, which will give you more clearance.
Yarmouth Fiero SEP 27, 10:41 PM
I compressed the spring in my drawing based on the calculation that my 12" long 325lb spring should compress approximately 2 1/2" which leaves me with a static length of 9 1/2" with 3 1/2" of compression travel remaining. I still have room on the threaded strut tube to fine tune my ride height when I am done.
Yarmouth Fiero SEP 27, 10:45 PM
Thanks for the suggestion Fieroguru. I didn't think of that but it is certainly a simple solution to that part of my problem. Since I will probably have to get custom shafts made anyway, it might be easy to arrange for the suggested boots to be installed.