Found this in another forum:
Dan:
Almost without exception you will find multi engined models have one tank per engine. To get even fuel feed at the relatively large distances involved a single tank has to be run with a full pressure system (Cline or Iron Bay), or a separate pump on each engine.
Bill.
[link=http://www.rcuniverse.com/forum/m_2962605/mpage_8/key_/tm.htm]see it here[/link]