"Scott Skylane" wrote in message
...

So... I can firewall the throttle levers without overboosting the
engines
on a Seneca 2?

Doing so would exceed max rated M.P. by about 1". The Pop-offs are
designed to be last chance protection against overboost, and are not to
be relied upon in normal operation. See:

http://www.kellyaerospace.com/articl...bocharging.pdf

Look at the section titled "How do you spell relief" on page 8.

I think our overboost lights come on at just over 40 inches. I am pretty
sure you can go up to 42 for short periods, but I haven't tried. The
throttles on a stock Seneca II are quite sensitive - at sea level ours will
reach 40 in mp at about 75% of throw and you can get +/- 2 in by just
breathing on the throttles. Most of the time with the load and the runway
available I do not need to use more than 35 in so I don't even approach max
boost.