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I didn't want to redirect on the HS2's vs H4's thread, in which you guys are informative as usual. That's not sarcasm, I learn a lot reading Mark's forum. My question is, anyone have pics of H4's on LHD cars?
I'm assembling mine with two left hand floats to avoid fouling the brake master. But this means the space between the carbs is tight, so how were choke linkages done on Aussie police cars, for example?
I've tried to add an image of my assembly progress so far, feel free to point out glaring shortcomings.

Oops, I meant to upload this pic too...

Hi Velopackrat

Aussie Police cars had twin HS4's, not H4's.... Oh and we're right hand drive! Upside down maybe!

I look forward to find out the result as I still have to build up my LHD H4's... Has anybody got a correct float bowl to spare?

surely the easy thing to do is to convert them to single choke on which ever carb is most suited to it and blank the other one using the 'choke delete' option that burlen sell.


my set of h4 have only ran one choke for years (as do my hs2 in my sprint, but that's because the lh let hits the bulkhead if its connected to the choke mech!)

velopackrat wrote:I didn't want to redirect on the HS2's vs H4's thread, in which you guys are informative as usual. That's not sarcasm, I learn a lot reading Mark's forum. My question is, anyone have pics of H4's on LHD cars?
I'm assembling mine with two left hand floats to avoid fouling the brake master. But this means the space between the carbs is tight, so how were choke linkages done on Aussie police cars, for example?
I've tried to add an image of my assembly progress so far, feel free to point out glaring shortcomings.

IMG_0307.JPG

I had 2 HS4's on my 1275, and only ran 1 choke; the other carb I left disconnected from the choke cable.I only needed 1 choked carb to start the engine. It was easier for me to run the choke cable from the bottom of the carb. I passed the inner cable through a clevis pin that was attached to the choke actuating arm ( the clevis was splitpinned into the carb lever and had a hole through the centre of it big enough for the inner cable to pass through, but small enough not to let the choke outer cable pass through).The outer cable abutted the clevis pin when cable fully in, and choke fully off. Then I made a top bracket that was a 90 degree angle that bolted between the two carb air filter inner bolts. This bracket had a hole through it big enough for the inner cable to pass through. Then I clamped the inner cable with the original carb cable fitting on the other side of this bracket after the inner cable passed through.Now when I pulled the choke cable. the outer cable did the pulling on the carb, as it was trying to straighten by pulling the inner.I found this very satisfactory, and avoided too many bends in the choke cable.

Thanks Gents,

Your feedback is appreciated.
Stupid me, why did I think AU cars were LHD? It's because I've never been there...
I also didn't know choking one carb was an option, hadn't thought of that. Yesterday I worked on a possible solution involving pulling the cable offset toward the left carb. I'll dry assemble it today and post up a pic to see if you guys think it will be effective. And in the meantime study up on what a 'choke delete' kit is, thanks Rich!

The following has no historical accuracy and may never have been used before. However, if you really want to run both carb chokes, you could perhaps adapt the dual cable choke cable from a Triumph TR6 so you operate each carb's choke individually instead of using a linkage.
http://www.bpnorthwest.com/choke-cable-dual-tr6.html
Early ones were stranded aircraft cable, later ones solid core wire. It is my understanding that some TR7 also used such a cable.

However, if you don't make a custom knob for the Triumph choke cable it would never look correct in an early Mini.

Doug,

Thanks for the lead on the Triumph cable but I might try Rich and Leon's suggestion of a single choke.
I tried my angled fix, one cable pulling two choke levers, but it takes quite a hard pull on the choke lever. Too hard. I suppose lighter return springs might help, or better geometry. But space is the issue... see pics

I have also used single choke on many of my H4 sets. It works fine & doesn't get in the way when using 2 left hand bowls.

PS. That looks like a very nice set of H4's.

I agree on choking one carb. All of the original LHD SU specifications call for no chokes to be fitted (used for racing).

You will need one of these http://sucarb.co.uk/thermo-jet-bearing-kit.html

and assuming you have .90 needles/jets, one of these http://sucarb.co.uk/h-type-thermo-jet-090in.html

assembled like this,

Gentlemen,

Great information, thank you again. Not knowing about Thermo-Jets, I modified an .090" jet nozzle and will hopefully accomplish the same thing. Unless you guys say otherwise.
I removed the H fitting at the base of the nozzle, cut an additional ring groove for a circlip and now the nozzle is captured on both sides of the adjusting nut. Kind of blurry in my pic but you can see the outer retaining clip.
The action of the choke cable is now reasonable and it should work fine.

Regards,

Chris