The sequence below is from when I cleaned a piar of SU (Skinner's Union) HS8 carburettors to fit to my Rover SD1 3500.
The HS8 are have a 2" (50.8mm) bore and can flow over 200cfm each. Since the 3.5l V8 needs only 450cfm, this should give it everything it needs. Now if it wasn't so clapped out, I should now be able to reach 6,500rmp.
I like SU carbs. Pick a needle (the hard part), choose an oil for the damper pots, set your fuel mix and idle and your done. These carbs come with AAA needles, which should be fine, though the reading I've done recommends finding some AAM (richer) or AAB (richer again). As they have been designed to maintain a constant air velocity over the fuel jet, they are very good at maintaining your fuel mixture. The down side is that they don't produce that squirt of rich fuel mix when you put your foot down that gives that kick in the pants you get with American carbs. When you're taking off, this means that you're not the first off the mark but because your fuel mix doesn't lean off after that initial impulse you mantain constant acceleration and very soon begin to pull ahead. It also means I can have a very big carburettor and not loose low end torque and power.
If you need to know more about SU carbs there are many sites explaining how they work such as this. The carburettors themselves are still being manufactured by Burlen Fuel Systems.
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