Ignition Implications During Engine Build

Noah · #1 07-07-2008, 07:20 PM

Getting ready to reassemble my IO-360 A1B6 after overhaul. I have not yet decided whether to go with the Lightspeed or the EMAG/PMAG in hole #2. (#1 will be a Slick, Impulse). I know that the Lightspeed requires some interface with the ring gear support if using the hall effect sensor (right?)

My question is, do I need to make this decision prior to building up the engine? It will sit for a while when complete, so I was hoping to buy some time to make the ignition decision. But IF I have to disassemble a bunch of stuff later to accomodate EI, it will force the decision now.

Any thoughts?

Thanks,

scard · #2 07-07-2008, 08:16 PM

You absolutely don't need to make this decision at engine build time. You'll be fine if you ultimately decide to go the lightspeed direction

.

Pmag owner (90hr.) -> lightspeed conversion proponent...

N941WR · #3 07-07-2008, 08:22 PM

The build has nothing to with your ignition so build away.

You can replace that pesky mag with duel P-mags at any time.

165+ hours of P-mag reliability.

Sorry Scott, I just had to add that.

Seriously, after helping a friend install a lightspeed over the weekend and knowing how reliable P-mags have become, I just kept shaking my head. So many parts w/ so many connections just makes me think those Lightspeeds can't be that reliable in the long term.

Noah · #4 07-07-2008, 08:24 PM

Thanks Gents-

I thought that modifications to the ring gear support were required if using the lightspeed? If so, perhaps I would hold off on installing the ring gear support and the starter / alternator?

AltonD · #5 07-07-2008, 08:30 PM

Well. . . . . .

I have the light speed plasma 3. It has not cranked yet.

I went with the HAL effect sensor in place of the right mag.

And here is why I didn't go with the direct crank sensor: The two bolt holes to mount the direct crank sensor plate are a hold over from a now no longer used crankshaft seal. If you have the holes, great! Bolt on the direct crank sensor. I, on the other hand, bought a factory new lycoming. Guess what, the boss is there, but it is undrilled an untapped. So instead of messing with the drilling on a brand new cranlcase, I went with the HAL effect sensor in place of the right mag.
Something to consider when making decisions and overhauling your crankcase (if it is an older crankcase, they are probably drilled and tapped).

mannanj · #6 07-07-2008, 08:30 PM

Personally, I'd go with the Lightspeed with the Ring Gear Pickup Option for the secondary ignition source.

It's my belief that the ring gear pickup gives you much more resolution for ignition timing because of the greater angular seperation on the ring gear vs. the smaller angle radius/circumfrence on the hall effect pickup in the other mag hole. (If this makes sense to anyone other than me!)

No proof, just gut feeling. Would love some feedback fron the Lightspeed folks.

N941WR · #7 07-07-2008, 08:32 PM

Noah,

The flywheel needs to be modified for the Lightspeed by having it milled to hold a small magnent which passes over a pickup bolted behind the hub to tell the thing when to fire. This pickup has wires that go to a brain box which then tells both coil packs to fire. All that stuff has to be mounted someplace.

The P-mags plug in like a typical magneto, two nuts and a few wires and you are set. Granted, P-mags had some teething problems but since they released a software upgrade this time last year the problems have gone away.

BTW, when building your engine, make sure to put the mag drive in, even if you don't plan on using it. Without that little part, the oil meant to lubricate that part will (may) go right out the breather tube. This happened to a friend and it cost him an engine.

AltonD · #8 07-07-2008, 08:35 PM

Quote:

Originally Posted by mannanj

Personally, I'd go with the Lightspeed with the Ring Gear Pickup Option for the secondary ignition source.

It's my belief that the ring gear pickup gives you much more resolution for ignition timing because of the greater angular seperation on the ring gear vs. the smaller angle radius/circumfrence on the hall effect pickup in the other mag hole. (If this makes sense to anyone other than me!)

No proof, just gut feeling. Would love some feedback fron the Lightspeed folks.

I talked to Superior and Mattituck at Sun N Fun this year, they both reccomended the ring gear.

flion · #9 07-07-2008, 11:32 PM

Until you put the prop on, it's not a problem to pull the starter ring off to modify it and mount the sensor board behind it. You'll almost certainly have made your ignition decision before then.

mahlon_r · #10 07-08-2008, 06:06 AM

The nose area of the crankcase needs to have holes drilled and tapped to support the Light speed crankshaft speed sensor plate. Although these holes can be machined with the engine assembled it is far easier to do with the crankshaft not installed. Check the bosses around where the nose seal installs to see if they are machined to accept the sensor plate before assembly. They may already be machined but they might not be. As one posted suggested, you could use the mag hole mounted Hall effect senor instead of the crank one, but I like the crank sensor better due to lack of routine maintenance and no moving parts.
Good Luck,
Mahlon