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Lycoming C4D5D or something else?

AviatorJ

Well Known Member
The engine I bought from Barretts Precision Engines is a rebuilt IO-540 using the core of a C4D5D. I'm down to the nitty gritty looking at operating parameters to set up my EFIS and what not.

When looking at Lycoming manuals the tables are broken out by series. Since my engine is an experimental do I just use these as an estimate? Maybe pick the engine with the comparable HP?

The C4D5D per the manual shows 250 HP, however I know mine dyno'd at 267, so they estimate at break in it should be around 285. Can I just use the tables for the 260 HP version?

Thanks!
 
The 250HP 540?s are usually 8.5:1 compression (same as D4A5 that Van?s sells) and redline rpm of 2575 (instead of 2700 of the D4A5). Verify with Barrett that it is safe to run it at 2700 then use the same parameters as the 260Hp and run at 2700. If not, use the same parameters and set to no more than 2575 at takeoff. The C4B5 is rated at 250Hp, but has the connecting rods and counterweights that allow 2700 rpm and this, 260HP.
 
Hey Jesse, the rebuild went to 9:1 compression. The test cell read out had RPMs as high as I think 2719 or something around there.

Edit: I don't know what I didn't think about going to Rhonda and asking her. She got back to me in about 5 mins and said that it would be 260 with stock pistons at 2700 rpm and I can use the operating info for a 260 Lycoming.
 
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Justin, can you post a link to the tables? I am starting the 180 page G3X set-up this weekend and would love to see what they recommend for settings.

I found a couple of POH's online and figured I would start there for EGT/CHT and other similar settings.

Thanks
Ethan
 
I'll email them to you. It's going to be cold tomorrow so plan on getting some more paperwork stuff together. I used someone's numbers on my G3X yesterday just to mess with the feature. It's really cool how customizable these fancy panels are!
 
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