Thread: New Project

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started looking at engine install today, Have to find out what fits where, clearances and routing of everything .

Subframe looks great, going to be a nice drivetrain!

Very nice work on the Caddy!

Ok guys I'm looking for input on my Panhard Bar setup. I'm mostly concerned with the mount I'm making for the rear attachment. I used 2 x 3 tube with .120 wall thickness. 1 " tube all the way through with a 5/8" bolt in that. I most likely will box in the 2 x 3 with studs sticking out to bolt to the axel. Having never built a car with parallel bars I'm not sure how strong the Panhard bar needs to be ? Thoughts ?
Is this location good in relation to the rear axel/ most I've seen are above the center line of the axel.


This pic is of the mount on the car, not sure what it used for in 1937 but it seems to be right for the bar attachment to the frame.

thanks for your inputs !!

Like you I'd be concerned with the box tubing, that's quite a distance from axle mount to the bar mounting. I like the idea of changing the bolts too, come through the box with bolts and weld the head of the bolt in the box. If needed, you could perhaps add a mount from the box to the axle tube and it would triangulate and spread the loading. Otherwise, I'd add some bends to the long tubing and shorten the axle mount.

My panhard bar on on both cars are from Pete & Jakes, mounted from drivers frame to two bolts holding the third member to the differential housing and two bolts holding the pinion shaft to the third member. I think the brackets to hold the heim are 1/4" - they are stout! The longer the bar the less lateral movement you get as the differential travels up & down, but the longer bar has more flex. In an easy swale where you're going straight there's not much force on the panhared bar, but consider a twisty hill country road where you're pushing the suspension to max G forces in a downhill S turn. You're putting the panhard bar in compression, then tension while going through a mid-turn dip that's trying to break the rear loose. Also, consider that as the differential travels up & down it moves fore & aft a bit in the arc of the parallel arms.Your panhard mounts are going to see those forces and have to be strong enough to put that movement into the bar flex, not the mount or the mounting bolt. Both ends of your bar rely only on the mounting bolt through the heim, in flex.

Your mount needs to be close coubled to the axle flange, and I would extend it above the axle tube an inch or so but I'd be very concerned with a single side mount that puts all of the force on the bolt through the heim. It needs to be supported on both sides so the bolt is only in shear. Same on the frame end, you need two plates welded to the frame solid to carry the heim. That existing frame mount won't last 50 miles,IMO. How about using a flat plate on the existingg axle mount, extending up with a second shorter flat plate welded to the tube spaced to fit the heim insert? Att the frame, makje a pair of triangle plates, rounded at the top, welded to the frame rail spaced for the heim insert. That would put your Grade 8 bolts in shear, and would be plenty stout!!

Here's a picture of one of Pete&Jakes panhard bar kits for reference - https://www.peteandjakes.com/parts/p...d-stock-width/

Originally Posted by rspears

My panhard bar on on both cars are from Pete & Jakes, mounted from drivers frame to two bolts holding the third member to the differential housing and two bolts holding the pinion shaft to the third member. I think the brackets to hold the heim are 1/4" - they are stout! The longer the bar the less lateral movement you get as the differential travels up & down, but the longer bar has more flex. In an easy swale where you're going straight there's not much force on the panhared bar, but consider a twisty hill country road where you're pushing the suspension to max G forces in a downhill S turn. You're putting the panhard bar in compression, then tension while going through a mid-turn dip that's trying to break the rear loose. Also, consider that as the differential travels up & down it moves fore & aft a bit in the arc of the parallel arms.Your panhard mounts are going to see those forces and have to be strong enough to put that movement into the bar flex, not the mount or the mounting bolt. Both ends of your bar rely only on the mounting bolt through the heim, in flex.

Your mount needs to be close coubled to the axle flange, and I would extend it above the axle tube an inch or so but I'd be very concerned with a single side mount that puts all of the force on the bolt through the heim. It needs to be supported on both sides so the bolt is only in shear. Same on the frame end, you need two plates welded to the frame solid to carry the heim. That existing frame mount won't last 50 miles,IMO. How about using a flat plate on the existingg axle mount, extending up with a second shorter flat plate welded to the tube spaced to fit the heim insert? Att the frame, makje a pair of triangle plates, rounded at the top, welded to the frame rail spaced for the heim insert. That would put your Grade 8 bolts in shear, and would be plenty stout!!

Here's a picture of one of Pete&Jakes panhard bar kits for reference - https://www.peteandjakes.com/parts/p...d-stock-width/

I see what your saying about the support of the Heim joint needing to be on both sides , thanks !

OK here's another look at the bar mounting

bar to be located in this area with tabs on each side to support the heim joint


Here is a pic of the rear where a shock was mount off to the frame (rear had leaf srings originally) Planning on fabricating off this point.
Thoughts ?

I'd mount the heim between the shoulders of that mount, or fabricate a new piece to fit using those mounts with Grade 8 bolts, but with the bar running to the passenger frame rail so it doesn't have to cross the third member snout. The problem on the frame end is that your heim needs to swing up and down for suspension travel, not front to back. Fabricate a pair of mounts to weld up towards the top of the frame, inside the C section, or even tabs that weld to the inside at the corner, top and outside surfaces.

rspears Thanks for the input ! I looked at that and when I measured the amount of rear side travel it was 7/16"and with the long bar its 1/8". This is going air ride on all corners with movement of 4" total, that's what I did the measurements from for side movement. Trying to keep bar parallel with the rear at ride height its all a pita.

Originally Posted by Navy7797

rspears Thanks for the input ! I looked at that and when I measured the amount of rear side travel it was 7/16"and with the long bar its 1/8". This is going air ride on all corners with movement of 4" total, that's what I did the measurements from for side movement. Trying to keep bar parallel with the rear at ride height its all a pita.

Navy, how about fabricating a new "shock mount" with a ~3/8 flat plate and a 3 sided extension, maybe a chunk of 2"x1/4 wall square tube to put your third member mount higher to clear the snout, and get your panhard bar closer to level at ride height. Mount the frame end at the bottom of the C channel, welding to both bottom and side. You could even add a couple of gussets to the square tube for stiffening, or use heavy wall C channel or rectangular tube. The 2" might have to be 2.5" or 3" to clear the heim insert. Just some quick ideas....

Originally Posted by rspears

Navy, how about fabricating a new "shock mount" with a ~3/8 flat plate and a 3 sided extension, maybe a chunk of 2"x1/4 wall square tube to put your third member mount higher to clear the snout, and get your panhard bar closer to level at ride height. Mount the frame end at the bottom of the C channel, welding to both bottom and side. You could even add a couple of gussets to the square tube for stiffening, or use heavy wall C channel or rectangular tube. The 2" might have to be 2.5" or 3" to clear the heim insert. Just some quick ideas....

Yup that's what I started this afternoon, pic's tomorrow. Thanks for your input.

hers's what have started for the rear mount, 3x3-3/8" angle and 2x2 -1/4 tube. Mounting bolts will be 7/16"-20 grade 8

another day of fun lol, welded an 3/16 " flat piece of steel to the 2x2 tube to give me the 1.75 ID I needed for the Heim joint. Cut height to just clear the body Sheetmetal. you see where I milled out for clearance. The pic makes it look thin on that side but its 3/16- 1/4 thick.

here's the latest, I had to cut up the cross section of the frame to get the parallel bars in place and these pic's show my fix .
3 x 6 tube used to rebuild the frame section.

after lots of cutting and still finish grinding to come. Pic shows full upward position of travel of rear