Lowering rubber bumper ride height to that of the chrome bumper cars – MGB and Midget

Midget:

The Midget is relatively simpler than the B.  At the front end, the chassis outrigger brackets which form the inner mounting for the wishbones need to be changed.  Alternatively, the lower spring mount can be spaced down from the wishbone, allowing the spring to protrude through the wishbone a little.  The spacer thickness should be half the amount that it is desired to lower the car, due to the position where the spring acts on the wishbone being halfway along it.

At the rear, fit lowering blocks or alternatively fit chrome bumper springs AHA8093.  (Note:  I have not done this particular change personally and have relied on parts book information as to which components changed between chrome and rubber bumper versions. Feedback welcome!)

MGB:

There are two methods:

The first and best method is a complete conversion to chrome bumper specs.  However, this involves quite a lot of work – changing to chrome bumper spec both the front subframe and the chassis mounting points for the rear spring.  The subframe itself is a simple bolt-on change but there are changes needed to the steering rack mounts as the rubber bumper cars shared the further forward rack position of the V8, and there is a small amount of work needed to create clearance for the new steering column position where it passes through the engine mount bracket.   At the rear, spring mounts are welded in place so this presents quite a major operation involving changing the last 12 inches of the chassis to a chrome bumper one for the rear shackle mounts, as well as swapping the front mounting bracket.

The second method, most commonly used due to the complexities above, is to use lowered front springs and lowering blocks between the axle and rear springs.  The disadvantage of this method is that it reduces the suspension travel by an inch and a half, so contact with the bump stops is earlier.  However, I have yet to hear anyone comment on this in practice.  It is probably only an issue for those who use secondary rural roads frequently.

There is a third option, which is be a hybrid of the other two – change the subframe at the front and use lowering blocks at the rear.  As the rear has more suspension travel, this can be a good compromise for those who might use their cars on more uneven roads.

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