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Which Carb?

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TexasSprite

TexasSprite

Jedi Hopeful
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My 59BE has a 948 40thou oversize block and a head off of a Cooper S (larger valves). Cam is unknown. The SU carbs on it look like HS1s with the long choke levers parallel to the manifold, but the carb bodies don't have the right profile where they hookup to the manifold. They look like HS2s at that point. The pots also have springs in them.

I have an extra HS1 and HS2 carb sets that I was thinking of having refurbished. Will the later carb work OK on my 948 or should I go with the original HS1.
 
HS2 will work fine but you need the manifold for them as well.
 
Could I piggy back off this thread? I was looking through my stash of stuff from the PO, nice set of original carbs off the '63, complete, good shape, dashpots are wet, air cleaners and everything, like it was unbolted and set in the box (which it was I'm sure).
Currently the 1098 has a Weber 32/36. I never tuned it up (never even tried really), but since the originals are pretty decent, I'm tempted to bolt them up and try.
Overall it seems the twin carbs are slightly preferred if they are set up decent, would you agree?
Basically it's a Weber vs. original question.
I like the purity of going original, if performance is decent and maintenance not much worse I'm leaning toward the twins. Which carbs would they be BTW?
I know they probably need a rebuild but I could bolt up the intake, attach the throttle cable and fuel and I'd know how they worked in a matter of minutes, right? It is that simple I think. Is all that holds the carb assembly to the engine the bolts on the intake? If so, wow, they stay put like that?
 
Very simple switch, go for it. Keep in mind the seals and such will need to be wet awile for them to swell back up tight. You may also find that the float valves need to be unstuck maybe.
 
The conventional wisdom is that Webers are good for HIGH rpm power and SU's are good for low rpm torque. Once set up both are supposedly relatively maintanance free. You should have AUD 73 tags on them .. blue springs, GY needles.
 
Good thing to play with in the winter, no?
Begs the question though, why did someone pull them off in favor of the Weber in the first place?
I hope it was because they thought spending $300+ would yield instant performance enhancement when I seem to find out form you all that the twins are every bit as good, better on the low end, perhaps giving up a bit to the Weber on the top end?
Currently the 32/36 bogs out under acceleration, gets 32mpg, needs to be good and warm to operate decent, has manual choke (which I prefer). Car tops out at about 80mph. I'd prefer a little snappier response. So I guess I have to either tune the Weber or play with the originals. (which would be what again, HS1s?)

PS
Bill responded while I was typing, seems I'm on track then.
 
While the SU's shouldn't bog (it a problem i've heard of in getting the webers tuned properly) they should only be tuned when the they are good and warmed up. I won't even think about adjusting mine unless the engine has been running at least half an hour.
 
Would be HS2's. 1 1/4 inch across the opening.
 
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