Avstar Aircraft of Washington, Inc.

10415 172nd St. E., Hangar A1
Puyallup, WA  98374
office (253)770-9964
or (253)770-0120
email:  avstarair@att.net

10-13-2001 Ask Mike! Archive
Can I upgrade Bonanza A-G models to an IO-470?

I'm out shopping for an older Bonanza.  I've found several of the A-G models that have higher time engines on them, and was wondering if anyone made a conversion to an O-470 for them?  If so, could I still run autogas in it?  Thanks!

First off, An E-series engine (stock in the A-G models) really isn't any more expensive to overhaul or maintain than an IO-470. Sure, you're dealing with older props, the fuel pump inspection, etc., but the newer engines have their problems also.
Yes, these aircraft can be upgraded to the 470's; I would use an IO-470-N, if it were mine to upgrade.  This engine is still well supported by TCM, is 260 HP, and is a pretty good unit.  The only O-470's (not injected) used in Bonanzas were in the H model; they had their share of problems, not the least of which was uneven fuel distribution, so a shortened service life. 
However, the structure is quite different to hold in a 470 than the E. Kinda spendy to upgrade; I recommend this only to owners that have had their bird long enough to get them otherwise how they desire (instruments, radios, paint, interior, general shape, etc.) Then, they are not starting over.
As far as my feelings about the use of auto fuel, please see my Ask Mike! Archive of 05-01-99.
Gear Green,