P-MAG question

[Gash]

It has been my experience that you can lean the engine to truly ridiculous levels.

I totally agree. On a recent cross country with my dual P-Mags, I cruised at 170 KTAS at 8,500 MSL, burning 7.8 GPH. If I hadn't recently calibrated (and confirmed) my fuel flow, I would not have believed it.

[Omega232Devils]

Larry,
You are getting some good data here. You can sum up my input by saying "+1"

I went from a Slick Mag and Jeff Rose EI to dual P-Mags, so I don't have the dual Slicks to single EI perspective, but I do have the single EI to dual EI. Going to dual P-Mags, I dropped about 1.2gph. Now before all the nah sayers cast doubt, let me caveat that with "at a price" as the drop in fuel flow was due to the ability to run really LOP. Lower fuel flows means slower airspeed. The further lean you go, the slower you go, so everything is with a price.

As for the increase in CHTs, I was able to get lower CHTs by switching to the B curve as I was able to lean further due to the increase in advance from 34-39 degrees. It is all in how you run your engine which curve works best for you.

One advantage not mentioned yet, is the starting ability of dual PMags. You will notice an easier time starting and will ignite mixtures the magneto with smaller gaped aviation plugs could not.

YMMV,

Dan

[N941WR]

Originally Posted by Juvat

I totally agree. On a recent cross country with my dual P-Mags, I cruised at 170 KTAS at 8,500 MSL, burning 7.8 GPH. If I hadn't recently calibrated (and confirmed) my fuel flow, I would not have believed it.

Same here and I have an O-360, not an IO-360. I typically cruise at 150 kts LOP while burning 7 GPH. Just stunning performance!

[Larco]

Thanks for all the reponses. I have experimented only a little so far and see about a 1 gallon an hour less fuel burn and some other improvements mentioned by some of you . I am convinced that adding the second P mag is the way to go. Should have done it sooner. 1000 hours times 6.00 dallors a gallon WOW. I can now run a little lean of peak and maintain the same IAS using less fuel. Balancing the injectors come next. Larry

[tkatc]

I have had issues with my dual PMAGS, but as mentioned here, they are still worth it and I will install them on my future RV-8. Not to mention the great service provided. As you've seen in this thread they will pay for themselves before long especially as gas prices rise. One economic point NOT mentioned in this thread is the low priced auto plugs that do a fine job IMO. They are able to use a larger gap, making a larger spark. And at about $2 per plug they are cheap and easy to replace at annual.

[ratc]

For those who have recently installed dual P-Mags. Did you use the Non impulse gear supplied by P-Mag or original lycoming parts? I have just removed a set of slick mags on an 0-320 D3G but will need a "new" pair of gears for the dual P-Mags I intend to fit. Where is the best place to buy them? Has the initial problems with those supplied by P-Mag been resolved?
Thanks as always.

[schristo@mac.com]

Originally Posted by ratc

For those who have recently installed dual P-Mags. Did you use the Non impulse gear supplied by P-Mag or original lycoming parts? I have just removed a set of slick mags on an 0-320 D3G but will need a "new" pair of gears for the dual P-Mags I intend to fit. Where is the best place to buy them? Has the initial problems with those supplied by P-Mag been resolved?
Thanks as always.

I talked to a couple of aviation salvage places at one of the shows and they both said that they had them available no problem... Later, I sent an emal to Wentworth and they gave a price of 95 or so just after I bought a reconditioned one from Emagair for 170.

[PaulR]

Why wouldn't you take them off the mags you removed and use them? I'm about to put a second pmag on in place of the LH impulse and just figured I'd use that gear.

[Brantel]

Originally Posted by PaulR

Why wouldn't you take them off the mags you removed and use them? I'm about to put a second pmag on in place of the LH impulse and just figured I'd use that gear.

The impulse mag gear is different than the non impulse gear.

You will need a non impulse gear and most likely shorter studs to make the swap.

Non Impulse:



Impuse:

[PaulR]

Brian,
Then can the spare gear from the mag I took out of the right side be used on the left side when I remove the impulse mag and change the studs? Same gear configuration?

Thanks