A MS440 ported from the factory???

[066 stihl]

Here's, a trick on 372 or 2171 saws. Everybody has a junk china 52mm big bore kit. Send it to US Chrome and bore it to 54mm and replate with the good stuff. Buy a new 2083 Jonsered 54mm one ring piston. Cut the top of the piston .050,come in .450 from the edge of the piston. Set the squish at .020 you will have around 220-230 psi. Alittle over a 5cu. saw in a 4.3 cu. The carb, needs to be drilled on the low side for more fuel. Now, you guy's may be using a bigger piston.

066stihl

 

[parrisw]

Cool, how much does a bore and re-plate cost?

 

[066 stihl]

It's been a few yrs not sure now. Call them.

066 Stihl

 

[parrisw]

It's been a few yrs not sure now. Call them.

066 Stihl

Thanks.

 

[tlandrum]

Here's, a trick on 372 or 2171 saws. Everybody has a junk china 52mm big bore kit. Send it to US Chrome and bore it to 54mm and replate with the good stuff. Buy a new 2083 Jonsered 54mm one ring piston. Cut the top of the piston .050,come in .450 from the edge of the piston. Set the squish at .020 you will have around 220-230 psi. Alittle over a 5cu. saw in a 4.3 cu. The carb, needs to be drilled on the low side for more fuel. Now, you guy's may be using a bigger piston.

066stihl

what class are you suggesting it run in? correct class or cheater saw?

 

[066 stihl]

That's one of my timber saws, I cut timber with. I don't race saws anymore.

066 stihl

 

[blsnelling]

No rod bearing issues with that much displacement and compression? Sounds like a fun build.

 

[stihl038x2]

Here's, a trick on 372 or 2171 saws. Everybody has a junk china 52mm big bore kit. Send it to US Chrome and bore it to 54mm and replate with the good stuff. Buy a new 2083 Jonsered 54mm one ring piston. Cut the top of the piston .050,come in .450 from the edge of the piston. Set the squish at .020 you will have around 220-230 psi. Alittle over a 5cu. saw in a 4.3 cu. The carb, needs to be drilled on the low side for more fuel. Now, you guy's may be using a bigger piston.

066stihl

So you're doing a pop-up piston .050" high ?

Steve

 

[bcorradi]

To my knowledge he has been cutting timber with that configuration for the last 3-4+ years on a 2171. His elbow acts up from time to time so he dropped the compression a tad (around 200 if I'm not mistaken) on the one he uses. I'm also certain he hasn't had any rod bearing issues.

 

[WadePatton]

That's one of my timber saws, I cut timber with. I don't race saws anymore.

066 stihl

tha's the man folks, say hello to Mr. Hennessee.

 

[Jed1124]

From start to finish one of the best threads on A.S ever. Welcome back Mr. Hennessee. Your libel to have a lot of folks wanting to send you there saw if you start hanging around here again.

 

[Arrowhead]

Here's, a trick on 372 or 2171 saws. Everybody has a junk china 52mm big bore kit. Send it to US Chrome and bore it to 54mm and replate with the good stuff. Buy a new 2083 Jonsered 54mm one ring piston. Cut the top of the piston .050,come in .450 from the edge of the piston. Set the squish at .020 you will have around 220-230 psi. Alittle over a 5cu. saw in a 4.3 cu. The carb, needs to be drilled on the low side for more fuel. Now, you guy's may be using a bigger piston.

066stihl

So... how many people googled US Chrome? LOL

Cool sounding build!! Thanks for the tip. :msp_thumbup:

 

[066 stihl]

Brad sent me the cheap cylinder kit. I ported and cut the piston .050 on it. I cut timber about two weeks with it and the piston came apart on it. So, I send it to US Chrome. No bearing trouble with it. It likes alot of fuel, never had a timber saw like that much fuel. I have a 2186 timber saw with a 395 piston in it.

066 stihl

 

[Stumpys Customs]

Nice, thanks for the tip. I've got the US chrome website bookmarked.
Hope you hang out more & share other handy tips.

 

[MCW]

Great thread and here I was thinking Brad had gotten drunk and forgotten what he'd ported

 

[066 stihl]

Saw Builders

Have you ever looked, at the bottom of the transfers, on the 385 & 372 jugs? With both jugs upside down and side by side look at, the inside cylinder wall and transfer. See anything that needs to be cut out?


066 stihl

 

[mdavlee]

Saw Builders

Have you ever looked, at the bottom of the transfers, on the 385 & 372 jugs? With both jugs upside down and side by side look at, the inside cylinder wall and transfer. See anything that needs to be cut out?


066 stihl

You talking about the lip that's at the top of the transfer tunnel where it turns into the cylinder. It's like it will almost make it compress before it can go through there.

 

[066 stihl]

No, Look at what's cut out from the factory on the 385. The 372 has it on the jug and go's down in the crankcase when the jug is on the crankcase. Think about more air and fuel getting to the bottom transfer.

066 stihl

 

[tlandrum]

i know what your talking about and most of us that port cut that wall out and window the piston.

 

[066 stihl]

Do you raise the wall up alot are just alittle?


066 stihl