We consider induced representations
$\operatorname {\mathrm {Ind}}_{\mathrm {P}(F)}^{\operatorname {\mathrm {G}}(F)} \pi $, where
$\mathrm {P}$ is a maximal parabolic subgroup of a reductive group
$\operatorname {\mathrm {G}}$ over a p-adic field F, and
$(\pi , V)$ is a unitary supercuspidal representation of
$\operatorname {\mathrm {M}}(F)$,
$\operatorname {\mathrm {M}}$ being some Levi subgroup of
$\mathrm {P}$. Imposing a certain ‘Heisenberg parabolic subgroup’ assumption on
$\mathrm {P}$, we apply the method of Goldberg, Shahidi and Spallone to obtain an expression for a certain constant
$R(\tilde {\pi })$, which captures the residue of a family
$s \mapsto A(s, \pi , w_0)$ of intertwining operators associated to this situation, in terms of harmonic analysis on the twisted Levi subgroup
$\tilde {\operatorname {\mathrm {M}}}(F) := \operatorname {\mathrm {M}}(F) w_0$. For
$\operatorname {\mathrm {G}}$ absolutely almost simple and simply connected of type
$G_2$ or
$D_4$ (resp.,
$B_3$), and
$\mathrm {P}$ satisfying the ‘Heisenberg’ condition, if the central character of
$\pi $ is nontrivial (resp., trivial) on
$\operatorname {\mathrm {A}}_{\operatorname {\mathrm {M}}}(F)$, where
$\operatorname {\mathrm {A}}_{\operatorname {\mathrm {M}}}$ is the connected centre of
$\operatorname {\mathrm {M}}$, our formula for
$R(\tilde {\pi })$ can be rewritten in terms of the Langlands parameter of
$\pi $, in the spirit of a prediction of Arthur. For the same collection of
$\operatorname {\mathrm {G}}$ and
$\mathrm {P}$, when these central character conditions are not satisfied, Arthur’s prediction combined with our formula for
$R(\tilde {\pi })$ suggests a harmonic analytic formula for a product of one or two
$\gamma $-factors associated to the situation.