H4 or HS4 SU carb, which one?
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They work very well indeed. ( #5 needle )
"Everybody should own a MINI at some point, or you are incomplete as a human being" - James May
"WET COOPER", Partsguy1 (Terry Snell of Penticton BC ) - Could you send the money for the unpaid parts and court fees.
Ordered so by a Judge
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One reason for the H4s status is its links to the Works cars. In the day, many event regulations required the use of the homologated manifold ..while allowing free choice of carbs.. H4s with their vertical mounting holes could be used with the "standard" Cooper manifolds... Paddy Hopkirk even developed a special carb that was basically a DCOE with a bit cast on to allow fitting to the standard SU manifold..... which met the letter of the law..
For those not restricted by homologation rules Special Tuning sold twin HS4 kits as bolt on items for the Mini.
Did Keith point out any actual performance issues when making a choice???
Cheers, Ian
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Question: I have many SU HS4 carbs lying around so why couldn't I just use two of those from an 1962 Austin Healey 3000? They do have offset mounting flanges. I noticed that the H4 has two parallel mounting holes on the flange. They also have a convoluted brass choke arm. I was on another Mini forum and they turned up their nosed at the HS4 carbs. Is this legitimate? Is their a significant difference. They appear much the same to me.
Dogscarf
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I shall have to be less cryptic in future.
Cheers, Ian
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If in doubt, flat out. Colin Mc Rae MBE 1968-2007.
Give a car more power and it goes faster on the straights,
make a car lighter and it's faster everywhere. Colin Chapman.
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Cheers, Ian
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I think the carb swapped over in '75/6 when the rubber subframes came in and the bulkhead crossmember gained a bigger dip to better clear the bottom of the jet.
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Dogscarf, did you check out the ST publication - AKD-5096 ?
It might have the info you need -
The peasants are revolting...
"Gone with the Wind" - a brief yet moving vignette concerning lactose intolerance
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If in doubt, flat out. Colin Mc Rae MBE 1968-2007.
Give a car more power and it goes faster on the straights,
make a car lighter and it's faster everywhere. Colin Chapman.
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Cheers, Ian
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cheers, ian
If in doubt, flat out. Colin Mc Rae MBE 1968-2007.
Give a car more power and it goes faster on the straights,
make a car lighter and it's faster everywhere. Colin Chapman.
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cheers, ian
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Yes, it is a variable venturi, but that is more advantageous for mixture control.
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Except that SU are variable venturi carbs so at less than full throttle the velocity will be the same irrespective of the carb size.....
"...Seems like there have been a lot of tuners who've tried a pair of HS4s, only to either go back to a pair of HS2s (or a single HS6/HIF44)..."
Not a lot of logic here.... (unless they're maybe looking for max economy)..if larger carb doesn't work (which is somewhat illogical in itself..) why would you go to an even larger one (i.e. the HS6)????
But of course there's always lots of "It depends..."
Cheers, Ian
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Dogscarf
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Seems like there have been a lot of tuners who've tried a pair of HS4s, only to either go back to a pair of HS2s (or a single HS6/HIF44).
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Question: I have many SU HS4 carbs lying around so why couldn't I just use two of those from an 1962 Austin Healey 3000? They do have offset mounting flanges. I noticed that the H4 has two parallel mounting holes on the flange. They also have a convoluted brass choke arm. I was on another Mini forum and they turned up their nosed at the HS4 carbs. Is this legitimate? Is their a significant difference. They appear much the same to me.
Dogscarf
If in doubt, flat out. Colin Mc Rae MBE 1968-2007.
Give a car more power and it goes faster on the straights,
make a car lighter and it's faster everywhere. Colin Chapman.
Found 23 Messages