Need help with Mustang II parts


May 12, 2021
I have a 1938 Plymouth Street rod that has a stock Mustang II front cross member installed. I just got the bushings replace in the upper and lower a-arms, they are painted and ready to bolt on the upper and lower ball joints. I believe the bolts to hold the ball joint to the a-arm are 3/8-24 thread with a lock washer and nut. I can't seem to find any spec as to how tight the bolts need to be torqued. I don't find anything is the common repair manuals, just that the whole a-arm is replaced. Any help would be appreciated.
2nd, anyone know where you can purchase a good power brake booster for a 74 Mustang II, that's what i'm using in my 38?
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I believe the bolts to hold the ball joint to the a-arm are 3/8-24 thread with a lock washer and nut.
Haynes manual doesn't seem to have a spec. Probably was riveted.

3/8 Fine thread grade 8 bolt should go about 37 ft/lbs.

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Yes, the ball joints were riveted from the factory, that's why there's no torque specs and everywhere suggests replacing the entire control arm. But the aftermarket supplies ball joints, most of the kits have bolts to use in place of the rivets. I don't remember seeing any specs when I replaced my ball joints, but it's been about 20 years now. And since I don't remember seeing any specs and if you're not able to find any, torqueing them to goodntight sounds about right. ;)

Seriously though, it seems like I just went through a thread somewhere that had torque numbers for different sizes and types of bolts, let me look for a few minutes and see if I can find it - and cross your fingers that that's what I saw..... :shrug: Otherwise goodntight should work. If you're concerned about them loosening up, a little red loctite should ease your mind. :)
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Well shoot!! You're the one that posted it!! :rlaugh:

I have seen the Rock Auto offer to rebuild my booster, but am afraid to send it in for fear of not getting it back/loosing it, then what. I found some info on my bolt torque question too. check out: Reference Guide.pdf This is a chart worth bookmarking/printing off and keeping. 177 inch/lbs = 14.75 ft/lbs too. The "K" in the chart is referenced at the lower right hand side of the chart. Thanks for all your help/suggesstions
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My 38 Plymouth when I bought it was a Fopar. It had a 302/C4 installed, but I wanted a Mopar, sooooo, I yanked and sold the 302/C4 and after recessing the firewall 6", I got a Mopar 360/727 bolted in place. I never felt comfortable with the drive train, so after some horse trading, I ended up with a 225 Slant 6/904 to be different. Currently the car has a stock Mustang II front crossmember, Mustang II master cylinder/power brake booster/brake pedal assembly, 11" Granada front disc brakes, Ford 9" rear end and even used Ford courtesy light switches in the doors for courtesy lights. I had to totally rebuild the floors, trunk floor, rear wheel wells, and made a new transmission cover. Have Nissan Maxima front power bucket seats, Grand Am rear bucket seats, have customized the dash, will have A/C, power windows, used a modified VW buss wiper system, have front door power windows and am hoping to have suicide rear door power windows (if I can figure out how to get the glass out of the door) AM/FM CD (Yeah old school now, but I have been working on this for 16 years). There will be a frenched rear license plate in the trunk lid and I have lots of other ideas that may get put in the car. Currently I'm trying to get the front end back together so it can be moved around the garage better. The engine is in process of being rebuilt, transmission has been gone thru. I was a machinist by trade, so have made many of the mounts/brackets needed. Hope this is helpful. I know it's not a Mustang, but has lots of Ford parts. Do have pictures and how - to for changing headlight switch in a 14 Mustang so you have always on headlights if someone is interested. I have seen at least a couple of how to do this on u tube, everybody else BREAKS stuff, my way doesn't and it works, minimum tools too.


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My 38 Plymouth when I bought it was a Fopar.
Thats really neat, loving the humpback body style. Looks like you have come along way.
It must really get some looks.:D:p;)
What a great red! She might be a little Fopar for life, but some wild stallion just improves the breed.
Thanks for posting pics.
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