• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Whitworth Source

MikeAH100M

Jedi Hopeful
Silver
Country flag
Offline
IN the process of helping a friend restore a basket case BN2 to an all alloy body racer (attached picture with my 100M at Pittsburgh Vintage Grand Prix). We are not going to reinstall the heater for now so need to blank off the heater hose connections to the block which are Whitworth. Any body have a favorite source of Whitworth hardware they'd recommend? 100 PVGP 2107 2.JPG
 
Doesnt make a difference to the thread only the head size is different . Its still a standard UNF thread .
 
Doesnt make a difference to the thread only the head size is different . Its still a standard UNF thread .

Not sure I understand/agree with this; are you referring only to this application? All the reading I've done on fasteners/fastening--mostly the Carroll Smith book--indicate Whitworth is subtly but significantly different than SAE, mainly in the slope angle and shape of the threads (don't have the book handy to confirm). Some seem to feel Whitworth fasteners are actually superior to SAE in some aspects.

Anyway, check this site out: https://britishfasteners.com/
 
Not doubting your reading and engineering data Bob but from a practicle perspective take two bolts of the same size one UNF and one Whitworth , lay the threads on top of each other and hold them up to the light and tell me they are different .Were not building the space shuttle here .
 
Here we go

The Unified thread angle is 60° and has flattened crests (Whitworth crests are rounded). From ​1⁄4 in up to ​1 1⁄2 in, thread pitch is the same in both systems except that the thread pitch for the ​1⁄2 in bolt is 12 threads per inch (tpi) in BSW versus 13 tpi in the UNC.

:cheers:

Bob
 
I believe what Mike is looking for is neither UNF or Whitworth.
Pretty sure the threads in cylinder head for the heater valve are BSPP, British Standard Parallel Pipe.

Mike , dont forget the valve on the water pump.
I generally get BSPP and Whitworth from BritishFasteners.com.
I can measure the threads when I get home if you need them.
 
Last edited:
UNF is nothing like Whitworth. UNC is close, but not identical. If you're mangling a bolt into soft alloy, you'll get away with the wrong one.
 
The new head is an expensive polished, ported alloy version so mangling is not in the picture! Thanks all.
 
IN the process of helping a friend restore a basket case BN2 to an all alloy body racer (attached picture with my 100M at Pittsburgh Vintage Grand Prix). We are not going to reinstall the heater for now so need to blank off the heater hose connections to the block which are Whitworth. Any body have a favorite source of Whitworth hardware they'd recommend?View attachment 52907


Amazon got em too
 
Back
Top