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Which carbs to keep?

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Whitephrog

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I have two spare sets of carbs, one of which will likely end up on a 948cc BE engine. Both are in about the same decent condition. First is AUC990 HS2 1 1/14" originally on a 61-62 Sprite MkII with a 948cc engine. Second is AUD549 HS2 1 1/4" originally on a 73 MG Midget with a 1275cc engine. So the question is, which set do I keep and which do I sell? I have intake manifolds for each.
 
I was faced with much the same question recently. I elected to go with the 549 because of the more sophisticated design. I have some of the ports plugged off but figured that when or if I ever needed them again in the future, they would be there for me. I have ample options for vacuum advance, PCV etc. Also, I figured the floating/spring loaded needle and the intake side bias of the needle where improvments to the design of which I would like to take advantage.

I would also like to add that, for the second time I can say that the well rebuilt SUs run the PANTS off of the DGV which it just replaced.

JACK
 
I would also opt for the 549s, if only because they are chronologically newer!
 
Hello Ray,

for me the one set to keep is the better condition set.

Personally I don't see why the biased needle was designed but it just seems wrong to have the needle rub the jet. If the latter set also has the waxstat jet, that was not a design improvement, similarly the poppet valve in the throttle disc.

Alec
 
If I keep the newer AUD 549 set can I still use the manifold from the AUC990 set? Is there anything about the AUC990 set that makes it operationally more appropriate for a 948cc engine?
 
I have two complete Bugeyes and a spare engine and transmission (actually most of the parts for a spare third car except for the body shell). It's highly unlikely that I would ever need the fourth carb set. So, I thought some one else might benefit from it rather than it setting on my shelve.
 
Joy is two complete Bugeyes and lots of spares, good on ya.
 
I'm with Donn on this one...hang on to them.

I had a box with about 8 sets of used SU's and several intake manifolds that I had picked up here and there and off Ebay (cheap). When I worked the deal for Hap to build my 1275 I also wanted a pair of his SUs on it. I took the box of cores for him to look through and he found a pair that "will do nicely". He also picked out an intake but made a comment "sure wish it had the round holes into the log, flows better". I had a mission...went home and checked out half a dozen intakes on Ebay over the next few weeks until Old Grey Norm posted one. Got it, delivered it to Hap, he's happy, I'm happy...HAPPY is good.

So, hang onto both sets if you can...you'll someday be HAPPY that you did.

Ray
 
Joy is extra parts. You will never need them til you get rid of them, and then it will happen. However, this page and the internet is a wonderful thing.
 
Hi,
I'm dealing with the same situation. If I use the intake manifold that the P.C.V. valve sits on then where do I plug the vacuum advance in.

Thanks,
Walter
 
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