Jump to content

MrFred 1965 Hillman Super Minx


Recommended Posts

Hi All,


I though I would start posting abut my latest upgrade to my 1965 Hillman Super Minx. A few months ago I bought 2 Weber IDF 40 down drought carburetors to fit. I know it will never be a speed daemon but I just like building things. Carb's are new to me as I mostly work on injected engines so this was bit of a learning curve (still is). 

I will add some more posts of the build when I get more time.


Here is a photo of the carbs when they arrived


  • Like 5
Link to comment
Share on other sites

As this engine has the intake and exhaust manifolds in one flange I have to build the Intake and exhaust at the same time. Using Solidworks I sketched up the flanges and got them laser cut out of 10mm mild steel. Shopping around I found that Stainless Design was pretty good on price and and had good service (also have a work account with them).


I started looking around for Extractor calculations to get the right size pipe diameters and primary lengths. I found it hard to find a reliable formula as some of the sizes seemed too small or too long.  In the end after talking to a few people I just went with best guess. My first design was 4-1 style extractors but after reading a few forms and doing some research I settled on a 4-2-1 design. Lucky there is quite a bit of room in my engine bay. 


In the end the Intake is 38mm, Exhaust is 32mm Diameter for the first 315mm then 40mm after the join with a total length of 1100mm finishing with a 50mm section


  • Like 9
Link to comment
Share on other sites

Built up the rest of the manifold. It was a little rough (ie not grinding down all the welds) as I planed to heat wrap (not sure any more though)20161229_150121_1484437023711_resized.jpg

Once Installed I had to build the synchronization link between the 2 carbs and run new fuel lines plus accelerator linkage. 

I decided to work late to get it all done. Finally finished it at about midnight and thought I would lake it out for the first run. Everything was going well until I pulled out on the the main road and the accelerator pedal fell to the floor. Luckily the idle was high and I managed to ride the clutch until I got off the road. Turns out I didn't put a split pin in the accelerator linkage and it was lying on the ground. After some tweaking I was good to go again. Definitely more power and acceleration.20161223_153609_1484437027860_resized.jpg

Hopefully I'll post a video of it running soon.



  • Like 6
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...