Porting a ms460

[jmssaws]

Is this an early 460 with mahle top end ?

Nope it's a stihl cylinder, just a good one

 

[jmssaws]

Looks moist

 

[junkman]

Its a water cooled 2 stroke ,been out for years jeesh .

 

[RI Chevy]

If it is an Alaska saw, then it was probably used to cut holes in ice and wet trees found floating in the water. Saw gets a little bit abused in order to stay alive.
Send it to Jason for a bionic rebuild. Lol

 

[jmssaws]

Look how sweet the factory bevels is . lol
I've not seen one like it

 

[RI Chevy]

Cool.

 

[huskihl]

This thing runnin' a dual port muff cover and hd2?

 

[drf256]

@MustangMike has a 460 jug like that. Huge perfect ports.

 

[RI Chevy]

Factory or from an engine builder?

 

[drf256]

Factory or from an engine builder?

Factory.

When we did his 460, he wanted to port his D jug. He had this crazy non-D 460 jug with ports on the edges of the piston skirts. Don't think I coulda improved it at all.

 

[MustangMike]

Still got it, was just checking it over today. However, based on how that 046-D saw runs, no regrets! But I guess I gotta find the carb spit back baffle ... but hard to imagine it will actually run stronger!

Sooner or later, I will use that jug on a 440 or 460, but we never did check the timing of the ports.

 

[MustangMike]

He had this crazy non-D 460 jug with ports on the edges of the piston

Did you ever pull the jug on the one you have to see how it compares?

 

[drf256]

Not yet.

 

[X 66 stang347 X]

I'm going to have to follow this build. I just got through with my 460 porting. And When you say early 460 Mahle cyl. When did that end? My 05' had stihl on one side of the cyl base and Mahle on other side.

 

[jmssaws]

I'm going to have to follow this build. I just got through with my 460 porting. And When you say early 460 Mahle cyl. When did that end? My 05' had stihl on one side of the cyl base and Mahle on other side.

I have no idea when they stopped, maybe 01 or whenever the mahle stopped in the 066

 

[jmssaws]

Cut 030 from the base and 020 from the chamber,
Got a few hours of grinding to do then I'll see if it can handle my old 460.

 

[X 66 stang347 X]

Cut 030 from the base and 020 from the chamber,
Got a few hours of grinding to do then I'll see if it can handle my old 460.

Ok.My squish was at .025 when started and that would lower it to 15 with factory gasket. What I did do was cleaned up and blended the transfers toward the base. Shaved .007 off the base wth Dykem, a piece of glass and sandpaper and that gave me .018 squish.

Cleaned up and smoothed the intake with a sanding roll.
Opened up the exhaust 1.3mm on both sides

And bumped the timing up 7°.

I have yet to have a chance to tune it much in wood yet. But it was running rich at 14,200. How much more would I gain if I take some off the chamber and base? Thanks for the tip


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[jmssaws]

What's compression now?
180?

 

[X 66 stang347 X]

170-175


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[RI Chevy]

Nice! Very shiney shiney.