Post up your ported cylinder Artwork

[huskihl]

Just curious, and if you don't have it don't bother, but what does the case side look like at the lowers?

I don’t have a picture, but it’s in Shaun’s thread. The case is slightly smaller at the left and right entrance, and I believe it’s like that intentionally

 

[srcarr52]

I don’t have a picture, but it’s in Shaun’s thread. The case is slightly smaller at the left and right entrance, and I believe it’s like that intentionally

You think they are trying to create some tumbling?

 

[huskihl]

You think they are trying to create some tumbling?

I think they are trying to stop reversion, just like the 562 has at the edge of the triangle

 

[mettee]

I don’t have a picture, but it’s in Shaun’s thread. The case is slightly smaller at the left and right entrance, and I believe it’s like that intentionally

I borrowed scarrdude52's pic

So the crank is throwing the charge forward it looks like.

I'm just crunching the theory in my head. Just for fun.

 

[huskihl]

I borrowed scarrdude52's pic

So the crank is throwing the charge forward it looks like.

I'm just crunching the theory in my head. Just for fun.

I don’t really look at it like the crank is doing anything (but hell idk). In my mind, the piston is coming down and pushing the charge up through the transfers

 

[MustangMike]

IMO, you are both right!

 

[huskyboy]

I guess the one way to find out would be to ask the chief engineer questions on the motor design?

 

[srcarr52]

I think they are trying to stop reversion, just like the 562 has at the edge of the triangle

Usually reversion lips are not very deep. They are aimed at keeping precipitated fuel from traveling back up the port wall. You sometimes see shelf’s like this to catch oil with a hole or drip channel to feed it to the main bearings but that isn’t the case here.

 

[huskihl]

Usually reversion lips are not very deep. They are aimed at keeping precipitated fuel from traveling back up the port wall. You sometimes see shelf’s like this to catch oil with a hole or drip channel to feed it to the main bearings but that isn’t the case here.

Yep not certain. I figured there was a reason it was like that with pretty much the entire 5 series and only having 10 to 15° BD. Even though the lower transfer port layout is slightly different across the line, there is a step in each model where they could have easily matched it up

 

[srcarr52]

Yep not certain. I figured there was a reason it was like that with pretty much the entire 5 series and only having 10 to 15° BD. Even though the lower transfer port layout is slightly different across the line, there is a step in each model where they could have easily matched it up

All strato engines will have less blowdown than traditional ones. You need to front load the flushing of the chamber with the clean air before the fuel mix is reaching the bore.

 

[huskihl]

All strato engines will have less blowdown than traditional ones. You need to front load the flushing of the chamber with the clean air before the fuel mix is reaching the bore.

That seems to be the case with huskies. Stihls appear to be different. Mostly normal blow down numbers in the low to mid-20s for most models

 

[srcarr52]

That seems to be the case with huskies. Stihls appear to be different. Mostly normal blow down numbers in the low to mid-20s for most models

I think the design is a little different. I thought some of the stihls instead of backfilling the transfers where flushing the exhaust port/muffler with clean air.

 

[huskihl]

I think the design is a little different. I thought some of the stihls instead of backfilling the transfers where flushing the exhaust port/muffler with clean air.

Could very well be.
I was only curious, not trying to be argumentative. I always learn when I listen to you

 

[srcarr52]

Could very well be.
I was only curious, not trying to be argumentative. I always learn when I listen to you

Well I’m not 100% sure on that so I was hoping for confirmation. I have not had much experience with the newer stihl saws.

 

[mettee]

I don’t really look at it like the crank is doing anything (but hell idk). In my mind, the piston is coming down and pushing the charge up through the transfers

Yeah that too also. And I'm certain that is causing the majority of movement.

Thinking the crank lobes are up and the piston is down. Only one place the charge can go.

Is turbulence in the transfers good or bad?

 

[huskihl]

Yeah that too also. And I'm certain that is causing the majority of movement.

Thinking the crank lobes are up and the piston is down. Only one place the charge can go.

Is turbulence in the transfers good or bad?

No idear. Shaun might have some input on the turbulence.

 

[mettee]

I guess why I ask is...

It was explained to me that intake is better atomized by speed. And straight-er-ish runners flow better so....

 

[Ketchup]

 

[Ketchup]

 

[huskihl]

Know poasts in weaks


Good direction