Page 2 of 3

Re: Narrowing rear control arms

Posted: 12 Apr 2017 23:40
by icehouse
So here is a sneak peak at what we are building. Not only does it narrow the rear track but it also allows us to do some camber/toe progression changes. It's still in it's infancy, we haven't checking loads or figured out how exactly we are going to hook the heim joints to the main beam (Boswell Beam) Or where exactly we are going to place the rods (race rods) don't contact any part of the body under full compression. Also we are going to have to hook one joint on the crossmember in single shear. Either way I can't wait to have one in my car!!!!


Image




Image




Image

Re: Narrowing rear control arms

Posted: 13 Apr 2017 09:46
by duke
Hey Jeff, that is looking very promising. Here are some pictures I have been sitting on for a while. These are of the rear end of an Australian 810 (?) Bluebird race car. I have always thought that this would be a cool way to set up the rear end of a 510 with minimal impact to the body. It looks very similar to what you are going for except the inner links go to a plate on the diff housing. I would think that this would give a little better camber control than what your initial design.

Image3468251386_eaf9e15586 by Eldukerino, on Flickr

Image3468250706_22187edecd by Eldukerino, on Flickr

Image3468250526_6cf101c61c by Eldukerino, on Flickr

Image3468249488_cc2b98f5fd by Eldukerino, on Flickr

Image3467435889_02f6bd79fe by Eldukerino, on Flickr

Re: Narrowing rear control arms

Posted: 13 Apr 2017 12:15
by icehouse
That is a cool design! Sam and I talked about a similar style as well. For a 1 off it would be totally doable. As for making a production run affordable to the average Datsun dude may be tough. We need to figure out our goal suspension travel. IE trying to get the toe change to zero but what kinda camber gain should we shoot for?

Duke have you ever tested the amount of suspension travel you use in the rear? Maybe Keith knows?

Re: Narrowing rear control arms

Posted: 13 Apr 2017 13:58
by Byron510
Duke - those are some very cool photos... gets the noodle going for sure.

Byron

Re: Narrowing rear control arms

Posted: 14 Apr 2017 11:22
by bertvorgon
I can do a measurement next week for you. What it will be is the distance from the control arm to a body part seam. From this you can figure out the wheel travel. I touched this ONCE in all my years, never on the race tracks of any type.

It happened on one of our very fast drives (Duffy Lake) at about 115-120 MPH on a SEVERE bump, loading that side of the car..I heard and felt a "thump".

I would suggest that on rear bump we need about 2.5" minimum (1200# springs). I know I have 2.5 - 2.75 up front ( 300# springs).

That all being said, obviously my car is set up with lots of roll control for all the reasons (racey car). This helps with the camber and toe change, so as the travel goes up...so does the change of toe and camber..so that reverts to... WHAT are you doing with your car IMHO.

As I have talked about before, all this is moot of you run a crap tire, all the G-Whiz setup is NOT going to do any good if you run Sears Roadhandlers, what is the point.

So, given you are aiming for a true handling enthusiast, keeping camber negative and no rear toe out would be the aim.

Jeff, as you and I discussed, if the SHOCK becomes a factor of letting the car pull the wheel up if droop is too stiff, that just screws things up as you well now experienced.

Re: Narrowing rear control arms

Posted: 12 Jun 2017 22:17
by icehouse
More updates!! I'm sure some of you guys got to see this at Canby, but for those who didn't! We also test fitted the arm today. It worked out better than we expected, it will require cutting out the nub off for center the stock spring. Which we didn't care to much about. as of now it almost goes as low as the stock arm. Maybe an 1" off. With a slight design change we should be able to get where we want to be. Now for the pics. O and this is a 14x8 -6 Star shark wheel (my favorite JDM wheels so we had to borrow one from Dillon for test fitting.

Image


Image



Image



Image



Image



Image



Image

Re: Narrowing rear control arms

Posted: 13 Jun 2017 23:19
by McShagger510
O_RLY-Quite.jpg
O_RLY-Quite.jpg (38.62 KiB) Viewed 403 times

Re: Narrowing rear control arms

Posted: 12 Oct 2017 12:35
by icehouse
Been a while since we updated. As per normal we've changed the design a few times, Sam is a picky bastard.... My response is usually "But I just want to drive my car!!!" Well here is what we have now... The version above didn't allow us to change the suspension characteristics like we wanted. Then we drew the design Duke posted. We felt it's weak design feature was around tire fitment. The arm ended up looking like a "Z" for tire clearance. So why we decided to use only the inner pivot which makes it more of an "A" arm. Plus we ditched the odd loaded heim joint for a weld in spherical bearing. Next we are going to run it through FEA and weld up a prototype. Who knows when we will be able to sell any.




Image


Image

Re: Narrowing rear control arms

Posted: 12 Oct 2017 14:26
by 510rob
Doesn't Solidworks have a rusty Datsun sheetmetal surface option? That chromey one is too good!

Nice work Jeff & Sam (and don't forget the patience of both of your families!)

Re: Narrowing rear control arms

Posted: 12 Oct 2017 14:27
by 510rob
icehouse wrote:"But I just want to drive my car!!!"

Oh easter eggs!

Re: Narrowing rear control arms

Posted: 12 Oct 2017 19:45
by gooned
Skillz

Re: Narrowing rear control arms

Posted: 13 Oct 2017 12:59
by bertvorgon
What I need to know...is how much is COKE kicking in for the advertising...?

Re: Narrowing rear control arms

Posted: 17 Oct 2017 00:17
by datsuntech
Feel free to bitch slap me if you like, but if you're going to go to all the trouble of making a completely new control arm, why not make it so that you can use a bolt on hub like on many newer cars? This would effectively shorten the bearing area giving you more room for a longer shaft. My thought is if you are going to change this much wouldn't you want to go to CVs at the same time? The issue with CVs is always that the shafts are too long and need to be modified. This would give you more room for a longer shaft without widening the track width.
This of course is completely selfish because It's something I have wanted to do for some time but don't have the time to dedicate to this sort of project.

Brock

Re: Narrowing rear control arms

Posted: 17 Oct 2017 07:41
by 510wizard
datsuntech wrote:Feel free to bitch slap me if you like, but if you're going to go to all the trouble of making a completely new control arm, why not make it so that you can use a bolt on hub like on many newer cars? This would effectively shorten the bearing area giving you more room for a longer shaft. My thought is if you are going to change this much wouldn't you want to go to CVs at the same time? The issue with CVs is always that the shafts are too long and need to be modified. This would give you more room for a longer shaft without widening the track width.
This of course is completely selfish because It's something I have wanted to do for some time but don't have the time to dedicate to this sort of project.

Brock

And also no more bearing preload stuff using the "A,B,C " spacers(as I mentioned previously) and a new nut every time you need to disassemble. It would be a lot easier to build, just a plate to bolt the hub too, no machining a housing for the bearings and no adapters for the CV's.

Re: Narrowing rear control arms

Posted: 17 Oct 2017 12:45
by JordanTr
I like s13/14/15 parts for the cartridge rear bearings. 4 and 5 lug availability. :D