Received Asian MS440 Big Bore Triplets Today

[MG porting]

Well, the tree guy I sold BB #3 to today stopped by and paid me, and he is very happy with the saw. I previously did a muff mod and timing advance on one of his 460s, which he said really woke it up, but his says the 440 big bore easily out runs it, and it a good deal lighter. (I lightly ported the BB cylinder, and did not do any port work to the 460).

Hey, I'm glad he is happy, and I hope it continues to run well for him.

Hek any time someone comes to give you money and not want to take it that's always makes for a good day. Lol

 

[MG porting]

In other news, BB #1 was the most "lethargic" of the 3 BBs that I did, likely because I left the intake too high. However, I also did not like the increased vibrations (of all 3 BBs).

So today I pulled the P+C off #1 and replaced them with an OEM 044 piston + cylinder. It is a straight fin cylinder, apparently made by Stihl (not Mahle). I tried to measure squish (while it was still on the original case), but my .050 solder did not give a reading. Found out there was a .040 gasket under that cylinder … no wonder!

W/O a base gasket, on an Asian 440 case, squish is .018 and the numbers were unimpressive … 103, 118.5 and 68. I planned to raise the ex a hair, and lower the intake, but I guess I did not remove enough for the Ex # to change (I was being a little cautious with an OEM cylinder).

I ended up with 103, 118.5 and 79. She fired up and ran nice (right before dark), hopefully I will get to put her in some wood tomorrow, and hopefully that annoying vibration will be gone or reduced.

FYI, the OEM 044 piston is 2.5 oz, the BB New West Pistons are 3.0 oz. That is a 20% increase. If you use the AM piston pin (I didn't), you add another 0.2 oz.

Will be interesting to see how this thing cuts compared to BB #2, which felt about the same as #3.

I'm more ceros about the vibrant hop it smooths out a little bit for you.

 

[MustangMike]

I'll run them and keep you posted about the vibs. It should reduce them a good deal, but the AV buffers and crank may not be as good as OEM.

FYI … piston weights … Stihl 044 (12 mm) 2.5 oz, Stihl 460 2.8 oz (12% increase), Meteor 460 and New West 440 BB (460 diam) both 3.0 oz. That is 20% heavier than the stock OEM 044 piston. I'm thinking a 12% increase does not change vibs a lot, but a 20% increase does.

It did not feel bad when I started it w/o b+c tonight, but I will run them all side by side in the wood and have better perspective on it.

 

[MG porting]

I'll run them and keep you posted about the vibs. It should reduce them a good deal, but the AV buffers and crank may not be as good as OEM.

FYI … piston weights … Stihl 044 (12 mm) 2.5 oz, Stihl 460 2.8 oz (12% increase), Meteor 460 and New West 440 BB (460 diam) both 3.0 oz. That is 20% heavier than the stock OEM 044 piston. I'm thinking a 12% increase does not change vibs a lot, but a 20% increase does.

It did not feel bad when I started it w/o b+c tonight, but I will run them all side by side in the wood and have better perspective on it.

Funny that the stihl 044 and the ms460 are really close in weight but I'm not all that surprised with the meteor piston they are pretty heavy not really sure why unless it's like the meteor ms660 piston there a little bit taller than the stihl and some of the other AM pistons.

 

[MustangMike]

In 046/460, I get the same squish with OEM, Meteor and New West BB. Meteor does have wider skirts than OEM.

My wheels are turning, I want to try a BB with an OEM piston. If it significantly reduces vibes, I'm thinking of replacing the OEM pistons in my 046/460s with Meteor and using the OEMs in the BBs!!!

 

[T.Roller]

In 046/460, I get the same squish with OEM, Meteor and New West BB. Meteor does have wider skirts than OEM.

My wheels are turning, I want to try a BB with an OEM piston. If it significantly reduces vibes, I'm thinking of replacing the OEM pistons in my 046/460s with Meteor and using the OEMs in the BBs!!!

I'd use the one with the widest skirts and widen your ports

 

[MustangMike]

If the Asian 440 runs smoothly with the stock 044 piston, my next build will be a BB with a OEM 460 piston. I'm pleased with the performance of the BBs, but don't like the vibes.

The only trouble with porting to the piston is that you can't swap to a different piston afterwards.

The biggest gains (lowest hanging fruit) seems to be getting the intake port at the correct height (for both 460, BB and 044). The intakes are often in the 60s, which just kills performance.

 

[MustangMike]

FYI, I ordered 2 more 440 kits.

 

[Lightning Performance]

I'd use the one with the widest skirts and widen your ports

and put it on a diet with one ring.

 

[MustangMike]

Now I'm going to have to put a ring on the scale!!!

 

[Lightning Performance]

Now I'm going to have to put a ring on the scale!!!

Lol

 

[Lightning Performance]

@MustangMike

Did I miss anything between page one and eight?
You can skip the usual problems. Anything new in there??

 

[MustangMike]

My postal scale is good, but not perfect. Sometimes a Meteor 460 piston is 3.0, sometimes 2.9. Adding one ring does not change anything, but adding a second results in 0.2 oz change. I'm going to conclude that each ring is almost 0.1 oz (just a little less).

 

[T.Roller]

If the Asian 440 runs smoothly with the stock 044 piston, my next build will be a BB with a OEM 460 piston. I'm pleased with the performance of the BBs, but don't like the vibes.

The only trouble with porting to the piston is that you can't swap to a different piston afterwards.

The biggest gains (lowest hanging fruit) seems to be getting the intake port at the correct height (for both 460, BB and 044). The intakes are often in the 60s, which just kills performance.

I'm aware of that.

 

[MustangMike]

@MustangMike

Did I miss anything between page one and eight?
You can skip the usual problems. Anything new in there??

The consistent problems with these kits are:

1) Chain adjusters suck. HL Supply's $8.- fix is the easiest way to resolve this issue.

2) Choke butterfly sticks closed, and the lever does not work well on OEM carbs. Reducing the diameter on the AM carb fixes this problem. If you want to use an OEM carb, cut a short length of 660 fuel line and put it on the end of the control lever (use needle nose pliers), and the OEM choke will function flawlessly.

3) Re the BB kits:

A) The intake ports need to be lowered to provide good performance. They are generally in the 60s. 78-80 seems to work real well. For those like me with more "carpentry" experience, 80 is about 9/16" from the base, w/o a base gasket. If you make the intake between 9/16 and 5/8", you should be good.

B) When using the provided pistons, there is a noticeable increase in vibes. I'm hoping to resolve this issue with lighter OEM pistons.

 

[MustangMike]

I'm aware of that.

Dave, I know your knowledge is up there, I try to post for those who are closer to my level. This is a big learning curve for me, but I'm enjoying it.

I don't have any delusions about producing the top saws out there, just trying to find the easiest way to make great performing work saws. (Mostly looking to harvest the low hanging fruit).

I appreciate everyone's input.

 

[MustangMike]

Some of the problems I thought were carb related were instead coil related. Always shorten the plug cord, and even then sometime these coils don't like to stick to the plug. I guess it is just part of dealing with AM stuff.

 

[Lightning Performance]

So the usual internals, the chain adjuster and oem lines/rubber where needed. Fix the carbs.
Do the standard bore next time with your best AM parts mix. They will be close and maybe smoother. Grind on them things Mike. Don't be scared....send you some liquid steel

 

[T.Roller]

Dave, I know your knowledge is up there, I try to post for those who are closer to my level. This is a big learning curve for me, but I'm enjoying it.

I don't have any delusions about producing the top saws out there, just trying to find the easiest way to make great performing work saws. (Mostly looking to harvest the low hanging fruit).

I appreciate everyone's input.

My knowledge is nowhere near alot of these fellas on here lol

 

[MustangMike]

Between having to go to Motor Vehicles and T Storms, I did not get to run any saws today.