Does the MS440 big bore kit make more power

[z4lunch]

Steve here... I have been eyeballing the big bore kits Bailey's has in there magazine for quite some time. Is it a quality kit...:jawdrop: does it make any more power than a stocker. I would be interested to know if any of you guys have run one side by side. With no other mods.
Thanks,
Steve

 

[Lakeside53]

What? NOBODY???? I thought you all bought them...

 

[Kneejerk Bombas]

Yeah, but you can't test it against the old one because it's dead, that's why you bought the new one!

 

[Freakingstang]

I can't speak for the 044/440, but the 046/460 BBKit wasn't anything spectacular out of the box. I was a little disappointed in the performance as I thought there would be more bang than the stocker.... It really shined when opened up, though. Just a mild woods port made all the difference.

The quality seemed really good. I have had two of them on differant saws and they seem to run and last pretty decently. IMO, a good deal compared to the cost of STIHL parts.


-Steve

 

[computeruser]

Calling Reddog...I know he has a BB440, I'm surprised I haven't seen him chime in yet.

 

[z4lunch]

ms440

Andy,
Steve here... Thanks for the bump...
I would really like some more feedback on the big bore kit.
Thanks
Steve

 

[klickitatsacket]

I can't remember if I ever ran them stock or not. I do know though that the 046 BB had a flaw in the design early on with the roof of the cylinder and it did not work as good as when they went back and changed it.

The 044 BB never had this flaw. With the 044 BB you are turning your saw into an 046 basically. You will notice some gains. If you are handy at all you might want to just buy the 046 BB and fit it on your 044.

 

[Reddog]

I have been happy with mine. Has more torque than the 440. Not quite as much as the 046. The castings are OK. Not as nice as the factory PC. But seems to be working fine after 5 gallons of fuel thru it. Mine is stock, no port work done to it

 

[Jacob J.]

The Bailey's BB 044 kits require quite a bit of work before installing but when properly done, they rock. I'm glad to hear the BB 046 was redesigned, those early combustion chambers sucked a tomcat's tits.

 

[Reddog]

The Bailey's BB 044 kits require quite a bit of work before installing but when properly done, they rock. I'm glad to hear the BB 046 was redesigned, those early combustion chambers sucked a tomcat's tits.

What work? Just bolted mine on and checked clearances.

 

[IchWarriorMkII]

So how big where the 460 BB kits increasing the displacement to?

I've looked at a BB kit as a rebuild option (since they cost the same as OEM via Bailey's)

 

[XJWoody]

So how big where the 460 BB kits increasing the displacement to?

I've looked at a BB kit as a rebuild option (since they cost the same as OEM via Bailey's)

The BB kits add 2mm to the bore, so it makes the 50mm 440 into 52mm 460 size, the 52mm 460 into a 54mm 660 size, and the 54mm 660 into a 56mm 880(?) size

(This is ASSuming that the con-rod stroke is the same between all those models, the overall displacement with the BB p/c would be that of the larger saw)

 

[Jacob J.]

Any of Bailey's BB kits are less than half the cost of a new OEM kit. They cost about as much as just a new OEM piston and rings.

What work? Just bolted mine on and checked clearances.

All of the 044 BB kits I ever installed had a lot of casting flash around the spark plug threads inside the cylinder. I used a wire brush attachment on my die grinder to clean all that flashing off. If you don't little pieces can break away and cause problems. The ports on the BB kits usually require some clean up work too, unless you don't mind crooked castings.

 

[Timberhauler]

Does anyone know who makes these kits??

 

[Sparky_NY]

I can't remember if I ever ran them stock or not. I do know though that the 046 BB had a flaw in the design early on with the roof of the cylinder and it did not work as good as when they went back and changed it.

The 044 BB never had this flaw. With the 044 BB you are turning your saw into an 046 basically. You will notice some gains. If you are handy at all you might want to just buy the 046 BB and fit it on your 044.

Didn't realize a 46bb could be put on a 44..... what sort of mods does it take? This sounds like a great way to go.

 

[klickitatsacket]

the 2 things that have to be changed are: you will need to slot the bolt holes at a 45* angle inwards. Then you will also have to put some spacers behind the lower bolt flange on muffler.

Depending on what your carburetor has in it for a jet and your elevation you may have to replace it with a bigger jet. You will be able to determine that after you set the carb.