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AH 100 carbs sizes
- Thread starter musme
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stevebn2bj7
Jedi Warrior
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Original size is 1.5", yes you can upgrade to 1.75" but will also need the correct size manifold. Do not know the size for 100s
B
BUNDYRUM
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Guest
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Hello glemon,
Just to let you know the regular 100/S didn't have a crossflow cylinder head. It had the 4 inlet and 4 exhaust ports on the opposite side of the head to the regular 100.
Best regards,
bundyrum.
Just to let you know the regular 100/S didn't have a crossflow cylinder head. It had the 4 inlet and 4 exhaust ports on the opposite side of the head to the regular 100.
Best regards,
bundyrum.
B
BUNDYRUM
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Hello again zblu, your right it's not a straight swap.
The head stud position is different.
The distributor is in the way and has to be moved to the regular 100 tach drive position.
I haven't gone into it completely at present but when I get to do my BN1 with the 100/S head I'm sure to find out.
The conversion has been done in OZ a couple of times that I know of.
Best regards,
bundyrum.
The head stud position is different.
The distributor is in the way and has to be moved to the regular 100 tach drive position.
I haven't gone into it completely at present but when I get to do my BN1 with the 100/S head I'm sure to find out.
The conversion has been done in OZ a couple of times that I know of.
Best regards,
bundyrum.
busybrit
Jedi Hopeful
Offline
Hi, my 100-4 came with std carbs, 1.5" I upgraded to 1.75"'s as I bought a very bad rotted out M spec converted car. It was a late 1953 bn-1 car.
https://www.youtube.com/results?search_query=austin+Healey+100&search_type=&aq=f
You can see the set-up on You Tube.
If you want to convert, the easiest way is to get a set from a TR3 OR 4 using parts from your 1.5" carbs, the bowls, copper cross tube and other fittings you can almost get them to look like the original M spec set-up available in the 50's. The manifolds are available at DW. I tried M spec needles and ended up using the TR3 std needles and M spec dashpot springs.
Johnb
https://www.youtube.com/results?search_query=austin+Healey+100&search_type=&aq=f
You can see the set-up on You Tube.
If you want to convert, the easiest way is to get a set from a TR3 OR 4 using parts from your 1.5" carbs, the bowls, copper cross tube and other fittings you can almost get them to look like the original M spec set-up available in the 50's. The manifolds are available at DW. I tried M spec needles and ended up using the TR3 std needles and M spec dashpot springs.
Johnb