440 to 460 Conversion

[chevyman]

I put the bb kit on my 044 and my 046 and never had a problem with either of them as far as fit. And they FLAT OUT CUT!!!!!

 

[Jacob J.]

something definately not right, a 460 has more hp than a 440 period so why would you have not gained anything by putting the 460 on a 440 case. if you ported it too high you would have lost some torque. ive never heard a complaint on the hybrid more hp and lighter than the 460. jmho

The 044/440 case doesn't have the volume that the 046/460 case does, and that has an effect on torque levels (base volume.)

I've built 20 or so of these, starting in '03 (I posted a thread here on it at that time) and I've never been able to make the same torque using the 440 case compared to the 460 case, even using different carburetors, ignition timing, etc. One thing I was able to do to give the 440 case an edge was to use a modified 064 piston.

 

[bcorradi]

Jacob - Have you've done many 064/066 conversions? Did you get similar results?

 

[Jacob J.]

Jacob - Have you've done many 064/066 conversions? Did you get similar results?

Yep and yep. The difference isn't as noticeable with the 064/066 but it's still there. Plus a person would want to make an effort to get the "improved" 066 crank with the 13 rollers in the big end rod bearing (although the failure rate on the 064 crank is low.)

The same effect is also present when converting an 056AV/Super case to a Magnum/Magnum II.

 

[wigglesworth]

One thing I was able to do to give the 440 case an edge was to use a modified 064 piston.

great......now i gotta buy an 064 piston.

 

[bcorradi]

Ok thanks JJ - I suppose the same goes for the 038 AV/Super to Mag.

 

[Carlyle]

Boy I almost can't wait for an update on this one.

 

[mtngun]

Stock exhaust (I shed some light on TW's pic).

Widened exhaust. So far it looks like just another aggressive woods port, not that there is anything wrong with that.

 

[Trigger-Time]

What is the idea or reason for the undercut at corners of cylinder base?
Only thing I can think of is a place to pry up on when removing cylinder.
But not all have them, This undercut is a way to tell if a 056 is a Mag II or not.
New OEM Stihl 064 PC kit I just put on has the cut and now I see this 460 cylinder
has the same undercut.

TT

 

[ironman_gq]

the 044 case is a little narrower at the cylinder base than the 046 cylinder so you need to clearance the outside edge of the base of the cylinder to fit the 044 case.


What kind of work needs to be done to get an 064 piston to work in the 046 jug?

 

[blsnelling]

My 440/460 runs right with my 372BB. The fastest cut times with each were equal. However, the 372 made more faster cuts than the 440, so seems to have a slight edge. Bottom line, the 440/460 hybrid is no slouch. It is my favorite saw, period.

 

[Brian13]

Will be following this thread with a lot of intersest! I have a 044 with a BB that I have been wanting to put a 046 top end on. Is there any difference between a BB kit and a OEM 046 jug?

 

[splitpost]

Will be following this thread with a lot of intersest! I have a 044 with a BB that I have been wanting to put a 046 top end on. Is there any difference between a BB kit and a OEM 046 jug?

Apart from the obvious ease of fitment the port size and cylinder quality are not the same as the OEM cyl,well not on the 044bb kit anyway.......

 

[Brian13]

LOL, I meant performance wise. The quality difference is one of the reasons I want to use an oem jug.

 

[epicklein22]

Yep and yep. The difference isn't as noticeable with the 064/066 but it's still there. Plus a person would want to make an effort to get the "improved" 066 crank with the 13 rollers in the big end rod bearing (although the failure rate on the 064 crank is low.)

The same effect is also present when converting an 056AV/Super case to a Magnum/Magnum II.

I find my 064 with 066BB lacks some low end torque. You just can't lean on it like other 66's. It still cuts pretty sweet though.:hmm3grin2orange:

 

[timberwolf]

It may well make sence that the BB on a smaller saw base is fighting its self a bit, the way the BB is ported it wants to run lower, but tight bases will favor higher RPM.

Took the exhaust port up another .5mm so exhaust durration should be just a hair over 160 once the bevel is on the edge of the port. Also took 0.022 off the base and slotted the jug bolt holes.

 

[timberwolf]

Took another .003 off the base to bring squish to .020 in.

 

[blsnelling]

Is your ceramic coating green, or is the lighting just weird.

 

[timberwolf]

Goes on green and comes out light yellow/gold once it is baked on.

 

[Carlyle]

I have seen one like that before!