042/048 top end on 044 bottom.

[Deets066]

Ok sounds good I’ll need to order one. Think I’ll build it and see if it’s a waste or not, how about skirt length? 272 shorter than and 064? Of course if piston is enough taller to keep me from having to drop jug as much I won’t need the long skirt to keep from freeporting.

272 skirt is shorter than a 64 or 46

 

[lehman live edge slab]

Next think I’m going to do is get my degree wheel.

 

[Canadian farm boy]

272 piston is on the right. 046 piston on the left

 

[lehman live edge slab]

Thanks, have to make my degree wheel and go to get some numbers. So should I get a oem 272 piston or meteor? If that turns out to be the way to go which it probably will since I looks like all port roofs are about .100 higher than an 046 jug. Just using the depth gauge on my caliper.

 

[Canadian farm boy]

Thanks, have to make my degree wheel and go to get some numbers. So should I get a oem 272 piston or meteor? If that turns out to be the way to go which it probably will since I looks like all port roofs are about .100 higher than an 046 jug. Just using the depth gauge on my caliper.

Since this is an experiment I'd be tempted to get the meteor piston just because they're a bit cheaper and if this doesn't work out, well you know.

 

[lehman live edge slab]

Yeah probably will but the cheaper one to try. Actually think I’m going to look for another 044 bottom to put this on since I have an 046 on the other one. But we’ll see can always put the 046 top back on if it doesn’t work out.

 

[lehman live edge slab]

Should I turn a pop up on the 272 piston since the 048 is domed?

 

[lehman live edge slab]

Why is the single ring better? I could see it being quicker revving but longevity wise not as good is it? I know husky likes the single ring. Have a few stihls that are but most are double.

 

[Deets066]

The single ring is a thicker ring, it lasts just fine.

Ring end placement

 

[lehman live edge slab]

Ok

 

[lehman live edge slab]

If I turn a pop up on the piston how much material needs to stay above the ring?

 

[MattG]

Why is the single ring better? I could see it being quicker revving but longevity wise not as good is it? I know husky likes the single ring. Have a few stihls that are but most are double.

Tuners like them because they offer less friction/drag. My tuning book reckons that if you ditch your second ring then is no compression losses above 8k revs, only (very marginal) gains due to less friction.

I guess on the plus side of keeping 2 rings, is improved stability of the piston in the bore, i.e. less likelihood of it tilting. But that's just a guess on my part.

BTW Lehman all the best with the project. Keep tinkering with stuff!

 

[cgraham1]

Well??

 

[lehman live edge slab]

Haven’t gotten past measurements. Look like they’ll fit but haven’t gone as far as putting together because I’ve been busy and it probably won’t run with an 044/046 hybrid so not sure it’s worth the effort but still may do at a later date just to see. I’m going to go get my lathe soon so I’ll have more tools to make it work.