Glen,
All infernal combustion engines benefit from a tuned exhaust, but as you know our model diesels are more tolerant to exhaust missmatch.
Will you get the same jump when it comes on pipe as a diesel as compaired to glow ???? that all depends on the individual motor, its bore stroke ratio and its porting. From my reading a diesel in general responds to a shorter tuned pipe as apposed to the same motor on glow but again there all individuals.
Stewart