Chris Delling wrote:
> I have a RBB, and no experience with S.U.'s. I know that different types
> were fitted to B's. Which type is preferable, and why?
Chris:
It's a matter of personal prefrence. The SU's fitted to MGB's were the
HS series and the HIF series. I run with the HS's, any comments
regarding the HIF's comes directly from the Haynes Carburetor Manual.
With the HS's, the entire device is much simpler. In fact, I have
totally dismantled my carb, in emergency situations, with the body still
attached to the intake manifold. There are seperate 'areas' for each
component, ie - the float bowl is independantly bolted to the body, the
suction chamber is easily accesible, etc.
The HIF has two unique features that make it more complex and, in some
instances, more desirable. HIF stands for 'Horizontal Integral Float
Chamber'. The float chamber is at the bottom of the carb body, sealed
by a large O-ring. While this arrangement elimantes the sometimes
troubling jet tubing found on the HS series, it also eliminates the
possibility of two minute float adjustments and fuel bowl cleaning.
The major advantage, in my opinion, of the HIF is it's temperature
compensation device. Down here in Mississippi, my HS's run fine in the
hot, humid summers. During winter, we go from 60 degrees to 30 degrees
in no time. The HS's, or at least mine, don;t take this well.
The HIF uses a bi-metallic strip of metal to control the height of the
jet (and consequently how much fuel gets mixed with the incoming air).
The HS series offers no such provision.
Of course, it's a personal choice. I had a chance to upgrade to HIF's,
but the HS's are still there. One thing is certain, though. Either SU
is better than the Z-S.
Thomas James Pokrefke, III
pokrefke@c-gate.net
1970 MGB
1995 Nissan Pathfinder
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