Carb numbers

steve williams

steve williams

New Member
Hi folks, can anyone explain/advise the different numbers used on HIF carbs. Those for my 3500 1973 read AUD 521. Is it poss to fit pairs of carbs with different numbers to the vehicle?
 
Hi Steve.
As long as they are a pair the only difference between early and late HIFs are the needles depending on compression ratio/ and having over run/ popet valves in throttle butterflies.
I normally solder the valves shut as they do give problems.
Clive .
 
Be aware that the tags could have been swapped at some point in the past, the only sure way to know is to look inside especially if they're missing.
It proved impossible to get a smooth even idle and good off-idle running on my carbs so I just lived with it, it wasn't until I had them both apart when changing the needles and compared one to the other that I realised the pistons were different (even though the casting numbers were the same).
I got another pair from a forum member (which seems to have cured the problem) but the carb with the distributor vac take off is different compared to my original carb, no tags on the "new" ones but the casting numbers on the bodies are the same.
 
ratwing said:
Be aware that the tags could have been swapped at some point in the past, the only sure way to know is to look inside especially if they're missing.
It proved impossible to get a smooth even idle and good off-idle running on my carbs so I just lived with it, it wasn't until I had them both apart when changing the needles and compared one to the other that I realised the pistons were different (even though the casting numbers were the same).
I got another pair from a forum member (which seems to have cured the problem) but the carb with the distributor vac take off is different compared to my original carb, no tags on the "new" ones but the casting numbers on the bodies are the same.
Click to expand...
our cars are old and have had a long life during which misdemeanours will have occurred....
 
You must log in or register to reply here.
Back
Top