MG MGB and MGB GT Tech Talk
One of these big springs in my HIFs is much bigger than the other. It is nearly twice as long as the other, and will hold the dash pot up all by itself, the other is not nearly that strong. I'm guessing these springs should match, but it's only a guess. Is this a concern?
thanks
walter
Walter,
It is essential that the piston springs are matched, for the carbs to function equally.
I would order a pair of new red springs. They are about $5 each.
Yes that would be a problem. Springs should have the same length when compressed by the same amount of force regardless of their size. It could possibly keep the pistons from rising and falling at the same rate which would make one carburetor richer under acceleration then too lean on overrun than the other.
Have a look at this page http://www.jcna.com/library/tech/tech0006.html under the section: XIV. PISTON SPRINGS -SU CARBS
It discusses how to identify the various SU springs and what their length should be given a specific amount of force on the spring.