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Inlet Manifold to Fit SU Carburettor to a Ruby
#1
I wish to fit a 1 1/4" SU to my Ruby and am looking for a suitable inlet manifold. I am looking for a separate manifold as I wish to fit a bunch of bananas exhaust manifold as well.

If anyone has one they would be interested in selling, please let me know.

Thank you.

Jamie.
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#2
TRY HERE
https://www.austin7ulster.com/new%20parts.htm
for either side draught, 30 degrees semi downdraught or downdraught inlet manifold. I presume you'll want the 30 degree semi downdraught to go with that 1 1/4" SU (ex-Mini)

I'd recommend ordering the blue spring and the No 6 needle while you're at it although with my Rosengart a No 5 needle seems to do a better job (rebuilt engine just back from workshop now need to run in my engine... similar set up as you're planning exhaust manifold not Bunch of bananas but tubular 4 into 2 into 1)

I've bought several parts from Paul Armstrong and in my experience he's ok
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#3
(21-05-2022, 04:06 PM)Michael D Wrote: TRY HERE
https://www.austin7ulster.com/new%20parts.htm
for either side draught, 30 degrees semi downdraught or downdraught inlet manifold. I presume you'll want the 30 degree semi downdraught to go with that 1 1/4" SU (ex-Mini)

I'd recommend ordering the blue spring and the No 6 needle while you're at it although with my Rosengart a No 5 needle seems to do a better job (rebuilt engine just back from workshop now need to run in my engine... similar set up as you're planning exhaust manifold not Bunch of bananas but tubular 4 into 2 into 1)

I've bought several parts from Paul Armstrong and in my experience he's ok

Thank you, Michael.

As you presume, I shall need a 30 degree side draught as I have a carburettor from an early Morris Minor 1000. It has a new, blue spring and, I think, an AH needle, but this is from a dodgy memory.

The ports on the linked manifold look a rather odd shape, but I assume that this is distortion from the picture. I shall give them a call and have a chat with them.

Does anyone know whether or not John Barlow is still trading? I tried to contact him a while ago, but to no avail. I was wondering what he charges for his manifolds, if he still does them.

Regards,

Jamie.
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#4
If your SU is from a Morris Minor I think you will find that it has an AN needle.   This was the standard needle and is a good choice for the Austin 7 engine.
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#5
It may be an AN needle: I cannot remember. I refurbished the device, fitting a new jet, spring, needle and butterfly spindle following suggestions from someone who has tested various combinations on a dynometer.

The plan is to fine tune the engine on the Dyno once I have sorted out the manifolds. I have made a number of modifications to the engine and I am curious about the final power output.

Jamie.
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#6
Has Tony Betts got no stock? That's where mine have come from and all the various options are in his list including the 30 degree.

Steve
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#7
Good point. Monday phone call coming...
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#8
(21-05-2022, 04:06 PM)Michael D Wrote: TRY HERE
https://www.austin7ulster.com/new%20parts.htm
for either side draught, 30 degrees semi downdraught or downdraught inlet manifold. I presume you'll want the 30 degree semi downdraught  to go with that 1 1/4" SU (ex-Mini)

I'd recommend ordering the blue spring and the No 6 needle while you're at it although with my Rosengart a No 5 needle  seems to do a better job (rebuilt engine just back from  workshop now need to run in my engine... similar set up as you're planning  exhaust manifold  not Bunch of bananas but  tubular 4 into 2 into 1)

I've bought several parts from Paul Armstrong and in my experience he's ok

Thank you for all for the suggestions. I have just ordered a manifold from these people. Paulwas very helpful when I called this afternoon and has been very prompt replying to e-mails.

Exhaust manifold next. ..

Regards,

Jamie.
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#9
would this exhaust manifold suit your needs??? http://www.southernsevens.co.uk/austin-7...gearboxes/
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#10
I would advise against using a 1 1/4" Su, unless you have a reasonably well tuned engine it will be too big so metering will be even more of a compromise. You would be far better off with a 1" or 1 1/8" instrument. To clarify the reasons; for an SU to work manifold depression causes the piston to rise and fall depending upon throttle opening and engine speed. If you use an oversize Carburettor the piston will only move a small distance rather than fully open when required, therefore you are trying to meter the fuel on a very narrow band of the needle. The consequence of this is lower performance than optimum in which case you may do better with a refurbished Zenith, they work well in good condition. Although most that have been through my hands need new throttle spindles at the very least.
Black Art Enthusiast
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