I recently purchased a Quest Terrier-Orion from my lhs and am thinking about converting it to 2 stages. I read that Bill Stine had some success with spacing engines up to 12 inches apart and having successful staging by utilizing vent holes to relieve pressure to prevent the stages from separating before the sustainer ignites. Has any one tried this method of staging and/or has anyone successfully transformed this rocket into a 2 stage? I have made up a rocksim file and run simulations and know that it will be stable as a 2 stage rocket, but am unsure about reliable ignition of the sustainer.