Hey! What’s everyone doing to strengthen the spring perches? I was at the track yesterday and after a couple hard launches I ended up splitting the yoke in half and making the perches look like a banana. There’s 2 shims under the perches for pinion angle , the u bolts are bent because the whole housing shifted forward 1/2 inch. All 8 wheel studs are bent and 1 axle has twisted splines. It’s a strange 60 as well. It’s a 69 charger 478 hemi stick car it launches hard and still in the breaking the clutch in steps. Im also dialing everything in as it’s a new combo. Any help would be great. Thanks.

This was a common problem back in the 70's on Drag cars.
The fix was to weld a brace onto the back of the spring perches.
Use at least 1/4 inch piece of flat plate to the back of the spring perch to the axle housing.
Make sure the perch is flat before you weld it up.
Good Luck

Sorry, I forgot to add, for the u bolts, you can go to NAPA and they should have an assortment of truck u bolts that are thicker.
(Be sure to measure the inside dimensions, so the new u bolts fit tight to the housing).
You will have to open up the u bolt holes in the shock plate, but you will not have any more issues with the u bolts stretching.

Try the Calvert racing heavy duty axle perches. about $50 a pair.

x2; I had Strange use them for peace of mind when they built my Challenger's S-60

Not sure if either of these pics show enough to make sense, but the Calvert perches are nicely boxed in, not simply "heavy duty" versions of a standard style

Using stock perches,than reinforcement is a good idea.

This...... Far superior, and the hole is the correct size too.

Ok thanks. That’s a great idea. Has anyone ever tried the ones from smith racecraft? There a square perch that welds to the same location as the stock perches but they eliminate using U bolts. I was wondering how they would work. Thanks.

Yep, this is what I did for the same problem.

I Imagine they work well, but you had better trust whoever welds them up to do a good job since the u bolts are not there to hold it all together should something come loose.

Had no issues with the Calvert ones but JFI we have bent up some cheap, hollow, lowering blocks

Like mentioned above - I also use heavy duty perches and box them in. I use Dr. Diff perches ($15/set) then blend in plates to the ends for a clean look. I’m not a fan of the Assassin bolt from underneath perches. There’s too much leverage pulling in too many directions for my liking.

Here’s a couple pictures of one I’m building now for an A-Body: