Thread: Triangulated four bar-Ford 9"

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Like the title says I got a triangulated four bar kit from Suicide doors:

http://suicidedoors.com/HeavyDutyUni...4-LinkKit.php#

And a Ford 9" rear axle. I was trying to figure out how to mount the upper control arms with an offset pumpkin, this proved to be a little harder than I had thought. The angles are gonna be pretty complicated to mount the tabs on top of the axle and I dont want to cut the arms to length until I figure them out. I thought of welding a 1/4" plate to the top to give me a flat even surface to work from. Wondering if you guys have any other ideas.

My lower control arms should be about 21.5" and the uppers will end up about 14" eye to eye. I think I figured out that the bottom control arms should be horizontal and the tops angled up about 4 degrees from what I can remember, does this sound right. It's a streetcar not a racer.

Sean

Sean, never personally done one, but maybe this stuff might help.

Don

http://www.streetrodparts.tv/Install...link-28-34.htm

If you scroll down, there are two sections on triangulated ones.

Billy Shope was one of the original Ramchargers, a group of Chrysler engineers who revolutionized drag racing in the 60's. I enjoy reading his explanations of suspension geometry. Herewith is some of it....
http://www.hotrodders.com/forum/how-...ht=Billy+Shope
http://www.hotrodders.com/forum/jour...81&action=view
http://www.hotrodders.com/gallery/sh...p?ppuser=17081
http://home.earthlink.net/~whshope/

Those are some good links (funny seems like the guy wants help but doesn't want to listen ). I'll have to take some measurements but just playing with the calculators it seems my top bar should angle down for 100% anti-squat . I'll check again later and post some pictures.

Another thought I noticed on Dons pictures they both have anti-sway bars (I think), should I put the one off the axle back on?? The more I read the more I get confused.

Sean

I don't know if this will show up but I got these measurements:
Wheelbase-120"
C of G (cam height)-20"
Rear lower arm-22", 9.5" front, 9.75 rear (depending on tire size, planning 30")
Rear upper arm- ?, 22" front, rear ?

It gives me a length of 11.2" and 19.44" up for the front pivot. Did I do this right??

http://home.earthlink.net/~whshope/id30.html

I just came across a post over at Hotrodders that says the pumpkin on the 9" is cast steel, it's not is it???

Sean

The third member housing (ring and pinion hsg) is cast. You should be welding your upper tabs to the stamped steel area of the axle housing unless you have a large pinion offset. Then one set may be on an axle tube. You didn't mention what you were installing this on. I would keep in mind that if both sets of links are parallel with the ground, there will be zero anti squat. No lifting or no squatting due to the links. Weight transfer will still make the back of the car drop some though. That is why most setups have the upper links angling down to the front in relation to the lower links. This is just enough to counter the weight transfer. Billy Shope explains this in his writings. The link Itoldyouso gave you has a lot of dimensions listed there. Install lower links first. I would install the upper link that is easiest to do first. I used poster board for templates drawn off the brackets you have in the kit. Trim these to fit and then transfer over to supplied brackets for trimming. The difficult side can then be done by mounting the frame bracket first. Set the link length to match the other side. Make sure the angle from side to side is the same as the other side and tack a temporary piece between link and axle hsg after you have set the angle in the vertical plane the same as the other side. A Smarttool level is very helpful here. Then use your poster board templates to trim to fit this side of the housing. Then transfer over to your supplied brackets. Tack everything in and move hsg through suspension travel before ever welding anything in solid. You may have to fabricate brackets due to offset housing. Study link Itoldyouso gave you. Hope this helps.