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Not sure if anyone can help, looking to replace the studs on a front subframe with bolts, Swift, I think, used to do a decent replacement, but no longer listed.

Also, had anyone actually nailed down a pattern for where front subframes with studs originated from?

I have had 63 dry, 65 wet, both were Austin, assuming that the subframes have not been changed is that the pattern?

Think may of answered my own question, Somerford seem to do a bolt that replaces the stud.

https://www.somerfordmini.co.uk/bolt-hy ... rame-tower

But then maybe not…….

So …….just checked and DRY front subframe thread size for both studs and bolts is 3/8 UNF

I only have a WET front subframe with studs ( not bolts) and thread size for the studs on that is 5/16 UNF .

Question is……..is the thread for a WET subframe with bolts also 5/16 UNF ?

Assuming it follows the same pattern as DRY subframes….

The 0505 part number of the nut indicates a 5/16UNF to me..... indicating that the bolt or stud will be the same unless I'm missing sumfink...

Thanks Peter,I was assuming it followed..

It is just in the back of my mind, I had been told, read or mis-remembered (probably the latter ) that the threads going into the subframes differed between studs and bolts and so they were not swappable…

This seems not to be the case, so far…and so you can pull out a stud and use a bolt instead…unless aI am missing some thing ?

I know the thread has moved on from the 3/8-5/16" studs that were common on the dry cars, since they became NLA, I make my own from head studs.

I suspect in the factory they used bolts on wet subframes to reduce the risk of damage to the hydro hoses when the frames were assembled but not fitted.

I am not sure if there was a pattern ( or what the pattern is) in terms of what subframe had studs and what had bolts.

Have heard various theories relating to studs and bolts, Austin used studs and Morris used bolts, etc etc….

I have both wet and dry subframes with studs and bolts and also both Morris and Austin…..its possible sub frames were changed of course

Also early 60s Dry with studs…

Not a fan of studs myself hence I am changing them, and went down this rabbit hole at the same time

The GOOD thing about studs is that you can leave the studs in place when you lift the body slightly to remove the steering rack. Lower the body after a rack refurb knowing that it will all align up.

NOT so with bolts - that might not align with the threads in the sub-frame. I'd suggest anyone changing from studs to bolts that they keep a couple of stude to ensure alignment should the need arise...... I wish I had done so.

Exminiman wrote: ↑Sun Jul 16, 2023 8:11 pm Not a fan of studs myself hence I am changing them, and went down this rabbit hole at the same time

Fair enough if your preference is bolts here, it's probably 6 and one half dozen,,,,,

I like studs because like Pete,,,,, you can assemble it by brail

To be honest, i suspect the motivation for using studs in the first place was something to do with getting over an assembly issue on the production line.

I just find it easier to line up with bolts, its when the holes dont line up straight away and body and subframe wont mate….noth8ng much in it really though.

Not sure if this old thread helps add anything....

Subframe Tower Bolt Sizes:-
http://mk1-forum.net/viewtopic.php?f=3&t=2452