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Swapping to later carbs

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drooartz

drooartz

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I need to rebuild my original 1-1/8" SUs on the Tunebug, as we've got some issues, and I think I'm in need of an overhaul. I was wondering about the wisdom so swapping over to the later 1-1/4" models. What else would have to change other than the carbs themselves? Do I need to worry about exhaust changes?

Just thinking out loud here.
 
Naa, bolt right up, and work fine.
 
Any real reason to make the switch? I know that the later 948 cars had them (and headers if I remember right). A bit more power, maybe? Any other reason?
 
I'd fix what I had and save the bucks for a 1275.
 
Seems to me that the dame old intake works just fine.
 
Drew, they bolt right up, and the intakes are the same. I think the HS2's are a bit less finicky than the H1's, and you'll see a tiny bit more power. HS2 parts are easier to get, and are generally cheaper than the H1 stuff. A worthwhile, period correct, upgrade, in my estimation.
Jeff
 
Drew,
One thing to consider is that if you plan on buying a 1275 in the future most don't come with the carbs, just the engine proper. If you get a set of HS2's now you can consider it the first step in the 1275 upgrade.
 
Drew,

Check eBay. You can usually find a pair of H2s in rebuild-able condition for around $50-60. I bought a complete setup not long ago (carbs, heat shield, intake, filters) for less than $60. They're fairly easy to rebuild. I haven't done the H2s yet, but rebuilt the H6s on my TR4 a couple of winters ago. The only work I outsourced was the throttle shaft ream/re-bush. I probably spent between $200-$250 for the H6 carbs/rebuild.
 
Thanks all for the clarifications. I've decided for now to rebuild the H1 carbs, but to keep an eye out for the H2s (and 1275/ribcase) for the future. The Tunebug budget is a little low right now, so I need to work with what I have for the time being. A few more things for the watch-out-for-them list.
 
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