Correct carb for 1275cc

[Chris Edgar]

The convertible has the carb which came when we bought it..it is an SU HS6 i.e. 1 3/4" diameter.
The Marina manual gives HS4 as the standard.

I wonder if I'd be better from an economy point of view replacing the HS 6 with an HS4.

What I'm trying to ask is;
does the HS 6 use more fuel for no return in terms of performance, would I get similar performance with more economy from a HS 4?

I'm more interested in economy than performance these days!

thanks
Chris

[bmcecosse]

The larger carb doesn't automatically use more fuel - but it does give YOU the opportunity to use more fuel by using the extra performance! So - if you want to limit the peformance and have best chance of economy go down to the 1.5" carb - or even the original 1.25" carb. If you really want economy - swap the 1275 for a 948 or an 848 if you can find one.......

[Chris Edgar]

Thanks for the answer....I don't think that I will be going smaller engined in my quest for economy though.
If I come across a smaller carb at the right price I would be interested to see the difference.
Meanwhile...just easy on the right foot!


Chris

[bmcecosse]

The auto trans is always going to use a bit more fuel......