wrote in message ...
On Wed, 29 Oct 2003 19:27:04 GMT, Roger Halstead
wrote:

:On 29 Oct 2003 07:33:14 -0800, (Dick Kurtz)
:wrote:
:
:looking at potential powerplants for my project I have come across a
:TSIO- 520 that is mid time,
:I am looking for an IO-520,
:What exactly does it take to convert an engine to non-turbo? Do
:higher compression pistons need to be installed? What of the
:injection system? Anyone out there a powerplant mechanic who knows
:his way around this issue???
:
:First, I'm not a mechanic, but having a IO540 that was turboed at one
:time...it will take a new set of high compression pistons along with
:rings and a hone job.
:
:The injectors are different, but "as_I_recall" you could use the
:injectors from the turbo. They are pressurized when used with the
:turbo.
:
:There's bound to be some one on here who knows the details.

The answer is simple - yes and no.

I don't know all the versions of the TSIO-520, so it depends on
whether it's turbo-supercharged or turbo-normalized. If, for example,
you're looking at the TSIO-520D off the V35TC Bonanza, it's
turbo-supercharged, and runs over 29" MP for full hp. It's
compression ratio is 7.5:1, and it makes 285 hp. The non-turbo
IO-520A makes the same 285 HP with 8.5:1 pistons.

There may be turbo normalized 520's - I don't know of any, but there
may be - that only run 29" MP maximum, and use the turbo to maintain
their hp to critical altitude. If that's what you're looking at,
unbolt the turbo and go fly. OTOH, 7.5:1 is a perfectly reasonable
compression ratio. If you were to unbolt the turbo from the 520D,
you'd give up some hp, but not that much. The O-320 A2B runs 7:1 at
150 hp, the B2C runs 8.5:1 at 160 hp.

If you do decide to increase the compression, Roger is right, it will
take new pistons, new rings and a hone.

You can certainly use turbo fuel injector nozzels unpressurized.

BTW, I probably won't be around much over the next few months, it
looks like I have a house to rebuild. If anyone knows of a good Cozy
project, I'm in the market, I haven't seen what's left of mine but
probably not much.

Did I miss something? Did the fires get you?
--
Jim in NC