All Alloy Cup progress

[AllAlloyCup]

They say that the lightest, fastest Supermaribe Spitfires
Were those that had no paint, just bare polished aluminium
And flush rivets.

To gain an extra 1mph top speed I have followed this design
feature to its logical conclusion on my AllAlloyCup.

I found these neat little stainless 4mm Domed coach bolts
on EBay and they will surely help with the streamlining?

Handy for those fixings inside the bonnet compartment.

Regards

Bill G
       

[AllAlloyCup]

           
Just stripped and rebuilt the OM SU and will fit the AN needle as advised plus have sorted out
A neat petrol filter. Waiting on some pipe bits to
To finish off.

I’ve an original tank , but unsure whether to coat the inside,
Or rumble some ball bearings in it, or let sleeping dogs lie?
I changed the filler cap to a screw on one.

Any suggestions about the inside of the tank.

Plus sent the rad shell off to the platers, so better start
Saving up!

Regards

Bill G

[Hedd_Jones]

Are you aluminium plating the cowl Bill?. That would look good.

One fabricated in Ali would be even sexier.

[AllAlloyCup]

Hi Hedd

By the cowl, do you mean the fabric cover that original GE Cups used?

I am planning to do machine turning on the bulkhead which is an
extra bit of bling I’ve been contemplating as well as replacing the fabric cowl
With an easily shaped alloy part to replace it?

I have a shrinker stretcher  and quite a lot of alloy sheet left over so I can probably
manage most of it myself. Would need to see how easy it would be to remove
In case I needed to do work under it though.

Will make a cardboard one, like the dozens of patterns I’ve made since the start!!!

Regards

Bill G

---

Perhaps by cowl you meant the rad shell? 
No it will be nickelled as it’s a steel chummy one.

At some stage I may paint the car... but not this year

Regards

Bill G

[AllAlloyCup]

                   
Here’s some photos of the throttle linkage and SU  carb pipe work and filter I’ve temporarily fitted.

Note the 3 x small loose collars on the throttle cross shaft to locate everything, two between the mounting points and one to locate the slow running lever against the stepped boss of the accelerator pedal. I’ll either pin these or drill and tap them for grub screws.

The carb is in approx the correct position, I used 2 ft of piping and put a coil in it to absorb some vibration that might set up between the engine and the bulkhead.

I soldered the banjo and Union using my Creme Brûlée torch... Now trying to figure out the optimum length/ angle of the control rod linkage from SU butterfly shaft to the operating end of the throttle cross shaft and pick two control rod ends which work smoothly.

I’ve got all the bits for the choke control too ( a pivot bracket, Ruby dash choke  and some SS 2mm rod. But can’t fit those till the engine and bulkhead are finally fitted. One or two minor steering wheel things to attend to before refitting the column .

All fiddly jobs but quite satisfying.

Regards

Bill G
aka AllAlloyCup













Sent from my iPhone

[Ruairidh Dunford]

Bill,

Have you considered fitting a pump?

[AllAlloyCup]

Hi Ruaridh

The level at the jet head is well below the bottom of the tank
And numerous posts have said that this SU set up can work reliably
As long as the tank has a fair level of fuel in it.

This OM has a throat slightly less than 1” so I’m happy to try out this
Arrangement with the AN needle.

I had a daft thought that the other way to ensure a full fuel feed
was to fit an Ulster type air pump? If need be an SU pump can be retrofitted.

Has anyone tried this out on a Chummy with a non cooking engine.
Eg standard valves and camshaft , but alloy HC head, lightweight pistons
and steel crank, I’m not planning to do racing!

If I can keep up with Jim H or Malcolm P I’ll be happy enough!

Regards

Bill G

[jansens]

I have been looking at how to do my throttle linkage too and I think I can do a simple linkage similar to yours (am using the same throttle linkage across the firewall but an DD SU) as long as I get the lengths right. You can buy the ball linkages of various lengths from Burlen new still. They weren't hugely expensive either. I was going to use one of the little clamp on brass arms on the throttle spindle on the carb maybe.

Simon

[AllAlloyCup]

Hi Simon

I have a brass cast lever on the butterfly spindle
and I’ve bent the end of throttle cross shaft so that
it’s roughly under the end of the brass lever.

There’s not a huge amount of travel on the throttle pedal
and I just need to make sure that flooring the pedal approximates
to maximum opening of the butterfly, so probably will need to
Sit the engine in the chassis, fit the floor boards and bulkhead and then
Cut a suitable short throttle control rods with nice movement at each end with
No stiffness and effective return spring( already bought)

Will post pics when I’ve figured it out!!

Pls post photos if yours is set up.

Regards
Bill G

[Ruairidh Dunford]

This was an effective temporary (and cheap) solution from a very similar set up that may help you as well.

https://www.amazon.co.uk/dp/B07CYT7MDQ/r...2112152270