Hi,
Like Sokol said, check the fuse delay. I bomb on ATAG mainly low level so I primarily use 4x250 GP, Ever-Ready on a 11 second fuse.
The bomb bay doors are spring loaded if your running the latest patch, so just hit your "drop ordinance" key.
As Muesli said, the clouds are loaded with ice, and even with carburettor heat on, (which should be switched on passing 8000ft), the Blennies engines are very sensitive to it, so they are best left alone until the devs see fit to fix them.
There is a thread with some videos by ATAG_Dutch on the Blenheim and a comprehensive post on the way I fly the Blenheim here.
http://theairtacticalassaultgroup.co...struments-only
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Hope this helps.
ATAG_Slipstream