making 7 hole adjustable trailing arm brackets

[tranz am]

Hey everyone, been a while, but I'm back on my project.
I decided to start this thread because I have been unable to find brackets for my trailing arms that suit my adjustment needs. I am also running NASCAR trailing arms which incorporate a mono ball bushing and a slightly wider bracket it s necessary to run them. I figure some of you might find this interesting or helpful.

heres where I started.
I have decided that it will be stronger with 8 holes instead of 6. I have upgraded the hole size to 7/16 and will be using fine pitch grade 8 hardware.

[tranz am]

Here I make a jig to keep the hole in the same spot.

[tranz am]

Here is the odd sized box tube im using. 3 1/2 - 1/4 thick.



Here I have carefully laid out and marked the holes. This takes a while I might add.

[bbcmudtruck]

Looking good so far! Please keep the updates coming.

[tranz am]

Thanks! Will do.

Originally Posted by bbcmudtruck

Looking good so far! Please keep the updates coming.

[tranz am]

I'm curious what some of you think about a radius bolt pattern on these brackets vs. the streight pattern ive designed.
I'm still kind of leaning towards the straight pattern. It would seem the axle location would determine the optimum placement of the radius curve dependent on spring height and how high or low the axle is in the frame to begin with. It seams trying to design it with a radius is kind of a shot in the dark without knowing this variable.
just curious about opinions here. I'll be uploading more pictures soon.

[tranz am]

Here are some more pictures.

I started over with a new tube because the original tube had a manufacturer defect that bowed the center sections inward.