Lewis wrote:
>
> I have a '77 rubber bumper B. I've rebuilt the entire front
> suspension including new rack & pinion unit, polyurethene A-arm
> bushings, new lower A-arms, along with new swivel hubs, kingpins,
> bearings etc. In other words, the whole lot.
>
> The car drove and handled much better then when bought from
> the PO. (It was so bad that the steering wheel would not come
> back to center during a turn: seized distance tube/kingpins).
> With the rebuilt front end as a baseline I decided to lower the
> front by a spring change (#480 rate) and install a Spax shock
> kit at the same time.
>
> Now that all the changes are done, I'm not that happy with the
> overall performance. My main problem is that there is a 'thump'
> that I can hear (slightly) and feel through the steering wheel. It
> seems to occur mostly on the down-stroke of the suspension.
> The lowered coil springs introduces a lot of negative camber
> onto the spindles/wheels/tires. How bad is this on the kingpin
> bushs and other stressed components? I'm not worried about
> tire wear.
>
> Has anyone else been this route and had the same problem?
> My goal is to prep the car for DSP class auto_x. Right now I'm
> running HS class, but would like to lower the car to c/b height
> which makes it 'not stock anymore'.
Lewis,
The "thump" you're hearing and feeling is probably the suspension
bottoming out on the bump stop. The May/June 97 issue of the Octagon
discusses ride heights and how shortened bump stops must be used for the
suspension to work. I can fax you a copy of the article if you don't
have it.
Question to the listers. Shouldn't you use a shorter spring to lower
the car rather than a different rate? Is a #480 stiffer or softer than a
standard spring? I'm guessing it is softer if it lowers the car but
doesn't that defeat the purpose of the lowering? Maybe a shorter,
stiffer spring?
Craig Brallier
75 MGB
76 MGB
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