cylinder boring

[Loanstar]

I have a poulan 3800 which has an unplated cylinder. Is there any reason i can't bore it out to its limit? As long as there is a piston to go along with the bore.

 

[Dub11]

I have a poulan 3800 which has an unplated cylinder. Is there any reason i can't bore it out to its limit? As long as there is a piston to go along with the bore.

The bigger the bore the less space your transfer tunnels will to flow. I've read of a few aftermarket BB kits that didn't pan out very well since space was robbed from the transfers.

Do you have a line on a larger, good plated piston?

 

[Loanstar]

I havent checked on a piston yet since I didnt know the pros/cons of overboring. I would like to go from 48mm to 50mm. This jug has large open transfers, maybe that will make it possible to still run well.

 

[Dub11]

I havent checked on a piston yet since I didnt know the pros/cons of overboring. I would like to go from 48mm to 50mm. This jug has large open transfers, maybe that will make it possible to still run well.

Got a piston in mind?

 

[Loanstar]

I haven't looked yet. I wonder if motocross or marine applications would be a good place to look?

 

[Sty57]

Bore and have it plated then your piston options open up.

 

[Al Smith]

Although I've seen the specs saying the bores on some saws were unplated I'm not so certain there isn't more to it .It would make sense to me that even if the cylinder was high content silicone content that eventually the cylinder would fail because the rings would effectively mill them right out .Also in those specs it notes the pistons were plated which again raises a question .
On that there is or was a process called "TIN" plating .It was really an anodizing chemical process that left a surface on the piston making oil cling to it .In more modern automotive engines it has been replaced with a teflon type coating .

 

[Loanstar]

All these points make me thinks trying other cylinders on my case would be better in the long run. Price as well. Maybe a 272 husky p/c? I need to find some trashcan cylinders to start measuring.

 

[Dub11]

All these points make me thinks trying other cylinders on my case would be better in the long run. Price as well. Maybe a 272 husky p/c? I need to find some trashcan cylinders to start measuring.

I've had that same idea go through my head to on using a 272 head on this chassis.

 

[Loanstar]

I've had that same idea go through my head to on using a 272 head on this chassis.

Have you done any measuring? If its close to start, a deal o the day cyl kit may be in my future.

 

[Dub11]

Have you done any measuring? If its close to start, a deal o the day cyl kit may be in my future.

Nope it's only in the idea phase lol.

 

[dieselfitter]

Something to consider. The wrist pin presses into the rod, bearings pressed into the piston. I might be a challenge to find a piston to accept pressed in bearings.

 

[Loanstar]

I wonder if there is enuf meat on the bone to machine it larger.