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rossco

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I have a spare 948 engine. The tabs on the carb float chambers are AUC983R and AUD 73F. Are they a mis-match and what would be the application for them by these numbers?
 
You might look through the back pages of "SU Carburetters (sic) Tuning Tips and Techniques" by Wade (Brooklands 1981). I looked briefly but couldn't find these numbers, as the list is indexed by make and model, not by carb number. Still, it probably doesn't matter--as long as they are H1 carbs, even if not original, you need only put in the right jets and needles and set them up according to Bugeye specs. I don't think there are any other differences between H1s

But, now that I've said that, someone will probably point out one or two differences...
 
AUC 983: Triumph Spitfire Mk1 1962 - 1966 950cc
AUD 73: Austin Healey Sprite Mk II 1962 - 1963 1098cc

Both are HS2 according to Burlen.
 
Scott,

What does the book say about AUC990?

Thanks
 
My hunch is they are from a later model car. The first tip off is the studs that hold the carbs in place are beefier than the ones currently on the car. The adjustment lash-up is also different, including the intake manifold. I appreciate any additional info you'all can add and thanks for the early responses.
 
Thanks Scott. I thought mine were original and that confirms they are.
 
rossco said:
My hunch is they are from a later model car. The first tip off is the studs that hold the carbs in place are beefier than the ones currently on the car. The adjustment lash-up is also different, including the intake manifold. I appreciate any additional info you'all can add and thanks for the early responses.
Click to expand...

Part number on the intake?

Fairly certain that the stated carb application is correct.
 
I suspect these are from a later Sprite. Is there an upside/downside to running the bigger carbs on the bugeye? The piston lift on one carb is firmly rusted in place. Is it necessary that that lift functions for the car to operate?
 
LoL, of course.
 
FWIW, The side brass tubes on the side of the carb body for the PCV system didn't show up to much later, like 1968 or so. The first HS2 have port advance on the front carb for the dizzy advance, and solid butterlfies.

Also worth noting for the 1275s, the earlier HS2 intake manifolds have small round holes leading into the balance tube on the intake, which flows alot better that the later HS2 intake which have large square hole leading into the balance tube. I bought up a bunch of the earlier HS2 intakes for SCCA limited prep race engine and that formula has slowed down a bit, so I have some of the ealrier 1275 intakes manifold I would sell, if anyone is interested.
 
Just a follow up on this, I'm prepping a set of HS2s today for rebuild, I never pay much attention, or remember the carb body tag numbers, even though I rebuild alot of these, just know the different features for the different years mostly, turns out the set I rebuilding is AUC 990, they are originally solid disc, vacuum port, no smog tubes, solid needle AN, which is early 1275. Hope that helps.
 
Thanks Hap. I removed the float chambers from both carbs. The carbs are numbered sequentially on the carb bodies as if they are a true pair. The little removable tabs on the float bodies, in this case, were totally different and they must not mean anything. I'm still not clear on whether the car will run if the piston is free but the lift pin is rusted in place. I assume you can center the jet from the piston orifice before the carb is bolted back in place.
 
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