twin su carb

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puchmaxikid
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twin su carb

Post by puchmaxikid »

hi, i was wondering if a set of twin mini 1 1/4' su would fit my morris 948? Also if they would, what would i need to do to achive this?
loz
bmcecosse
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Post by bmcecosse »

Yes they will fit - but they won't make much difference to the power output on an otherwise standard 948 engine !
You will need to use the standard exhaust manifold - and cut away the original inlet manifold to allow the twin SUs to fit. Or of course - buy a better tubular exhaust manifold.
Most now use a larger single SU carb - ex Mini, on a good alloy inlet manifold. Most of the power increase of either of these mods comes from removal of the exhaust heat from the ingoing air/fuel mix - but this may increase fuel consumption slightly. The hot 'vapourised' fuel in the original set-up may not give best power - but it does tend to give best economy.
Best mod for your 948 engine - is to swap it for a later 1098 engine !
If you want to keep the 948 - consider fitting the camshaft and head (skim 60 thou) from a 1098 and this will give the power of a 1098 engine at 10% more revs of course. Again - the larger carb from a Mini will give a bit more power - but not necessarily best economy.
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Kevin
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Post by Kevin »

Hi Loz have to agree with Roy, the twin carbs can look nice but can be a real pain to keep in tune, if you are doing it for looks thats OK but performance wise a better single carb is the way to go, if you want to read up more on the subject get a copy of David Vizards book.
http://www.amazon.co.uk/Tuning-Engine-D ... 1859606202
Cheers

Kevin
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