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Area 51% wrote:Not to worry about grinding on the magnesium. I've abandoned that fine, flaw-free piece of artwork in favor of an aluminum unit.

Just out of curiousity, what aluminum block did you go with? Do you need to perform any modifications to the new block to make it match with the AeroVee block? I’ve heard of people doing this but I’ve never actually heard from anyone who has tried it!

vwglenn wrote:Grinding on a magnesium case is a good way to start an unstoppable fire. Be very careful. Go really slow. I'd mod the cooler or the adapter if at all possible.

Magnesium isn't that flammable. In a solid form like an engine block you have to heat it up close to its melting point to get it to burn. In the unlikely event one of the chips ignites, just make sure it doesn't land on something really flammable, just like when grinding steel. The Aerovee instructions already mention a need to grind inside the case as necessary for clearance and nobody's admitted to igniting a case yet :-)

Mike,

The case I selected was a CB Performance unit. What I really liked about the case it is available with a taller deck surface, so no shims between the case and cylinders will be necessary. You can adjust the compression ratio from 8ish to 7ish with the head gasket alone. There are many other advantages that are part of the case as delivered. I'm not sure I've found them all yet.

There are several machining operations that are necessary to make it a viable option. Some can be accomplished with a hole-saw and grinder. Others need a machine shop. Due to recent events here, I'm not comfortable making my findings public. PM me, and I'll tell you everything I know.

Yes, it is heavier. But with my lightweight fuel tank, and future 5lb battery, I'll be looking for some ballast anyway.

A vixen file worked very well to make the necessary clearance between the cooler and bolt boss on the aluminum case. I would have used it on the magnesium as well, rather than take any chances with an uncontrolled fire.

I was hoping the magnesium case would be easier to light than what gammaxy states. I was going to cut it up and give it to Bryan for his boy scouts to use to start campfires.

Area 51% wrote:I was hoping the magnesium case would be easier to light than what gammaxy states. I was going to cut it up and give it to Bryan for his boy scouts to use to start campfires.

Here's a quick story (with a photo) about burning a Corvair cooling fan made of magnesium:

https://flycorvair.net/2014/05/31/thought-for-the-day-the-need-to-know/

FWIW,

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
169.4 hours / Status - Flying
Member # 109 - Florida Sonex Association
Latest video: https://www.youtube.com/watch?v=1VP7UYEqQ-g

Magnesium dust or fine chips will ignite with just a spark. The machine shop I worked in was fly cutting a mag. part when the cutter hit a grain of sand in the surface of the casting and threw a spark into the pile of chips. The fire cannot be put out with a standard extinguisher. water makes it explode. We had to cover it with sand and let it burn out.

Here's what can happen when you grind a mag transmission in a VW. Same material.

https://www.youtube.com/watch?v=3Yg5V65CLyM

Area 51% wrote:A vixen file worked very well to make the necessary clearance between the cooler and bolt boss on the aluminum case. I would have used it on the magnesium as well, rather than take any chances with an uncontrolled fire.

I was hoping the magnesium case would be easier to light than what gammaxy states. I was going to cut it up and give it to Bryan for his boy scouts to use to start campfires.

No need to cut it up...throw it on the fire, stand back, wait 5 minutes, get sunglasses out.