Little China Girl

[Stump Shot]

Not liking the relationship of the ports I decided to try a 288 style piston, went with a Hyway and a Cross bearing.

 

[Stump Shot]

Had to cut the skirt to clear the crank lobes. Took off .110" until it would clear.

 

[Stump Shot]

Once I was able to install the piston and have it go all the way around, I thought I would see how the numbers were.
No gasket
Squish - .049"
Exhaust - 103
Transfer- 124
Intake - 90

 

[Stump Shot]

The exhaust has a little bit of free port to it at TDC so now I'm kinda stuck as far as lowering it any more. Will explore other options including a welded pop up.
Seems like the exhaust and transfers are too low and the intake is too high. Also the big transfers are negated as half of it is coverd by the piston at BDC. The 288 piston did let it open up a little bit more.

 

[Stump Shot]

Maybe there's a better answer...

 

[Stump Shot]

Decided maybe I should take and rid myself of the actual problem. HSS bit and a subsequent carbide bit were no match for the hardness of this crankshaft. Made it shiny was all. Seems a little crazy on the heat treatment if you ask me. Lol

 

[Stump Shot]

Might be this whole rig needs a trip to Soddy Daisy for a "porting" job. Lol

 

[Stump Shot]

Well I decided not to put it back together as was my first inclination, hoping something else will come to mind to try, so I guess I'll sleep on it for a little bit. My thinking was I have another 288 piston so I would turn down the crank lobes and use the new piston, have my cake and eat it too. The only thing I'm eating now is crow.

 

[huskihl]

Well I decided not to put it back together as was my first inclination, hoping something else will come to mind to try, so I guess I'll sleep on it for a little bit. My thinking was I have another 288 piston so I would turn down the crank lobes and use the new piston, have my cake and eat it too. The only thing I'm eating now is crow.

A couple of my pretty good runners had about .050" freeport. Not recommending it, just saying. Ymmv

 

[Stump Shot]

A couple of my pretty good runners had about .050" freeport. Not recommending it, just saying. Ymmv

So making even more free port isn't as big a deal as getting the squish measurement to my target number?

 

[huskihl]

So making even more free port isn't as big a deal as getting the squish measurement to my target number?

In my limited experience, tighter squish is better

 

[Stump Shot]

In my limited experience, tighter squish is better

...and the fire coming out of the exhaust would be cool and stuff. I like it.

 

[huskihl]

...and the fire coming out of the exhaust would be cool and stuff. I like it.

It's been theorized that the outflowing exhaust pulls an extra bit of fuel into the case also.

I'm not much of a theorist muhself

 

[T.Roller]

Might be this whole rig needs a trip to Soddy Daisy for a "porting" job. Lol

Hey brother I'll port it with a whole mag of 5.56 if need be

 

[Stump Shot]

Hey brother I'll port it with a whole mag of 5.56 if need be

You're on standby dot dot dot

 

[T.Roller]

You're on standby dot dot dot

Got my sticker today, thank you!

 

[Stump Shot]

It's been theorized that the outflowing exhaust pulls an extra bit of fuel into the case also.

I'm not much of a theorist muhself

Well, if you open one window in your house not much happens, open one on the other side of the house and air flows through. So I can kinda get behind that theory I guess.

 

[Stump Shot]

Got my sticker today, thank you!

Welcome!

 

[T.Roller]

Welcome!

I'll have to make up some that say "Jug Slayer Work Saws"

 

[Stump Shot]

I'll have to make up some that say "Jug Slayer Work Saws"

Your motto can be "No Bad Jugs Here!"