Porting the 361 Big Bore

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Looks good.

Is the chain sharp? It looks like either the depth gauges are too high or the wood is dead, dry locust.

The second saw sounds pretty lean.

The chain is sharp. It just really hard, dead, frozen wood. I already richened up the 2nd one from the first runs I made. It got stronger. If it's still lean, then there's more in it.
 
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The 2nd and fastest saw is the 361BB. It is very strong in the cut. The runs I've timed here where after I had already richened it up a little. It got faster after doing so. There may be a little more there yet with some timed cuts and fine tuning. The OEM P&C are strong, but no match for the BB. The little secret I was joking about...a MS460 carb. Bolts right on with minimal mods from an initial 1st glance.
 
2nd saw clearly runs faster out of the wood.
Seems like the times are close enough that if you ported another pair of cylinders, the winner might reverse. OTOH, if the Mahle is fully broken in and the fast one is the BB kit, then that would make the difference more than it seems on the video.

Do they both have the 460 carb?
 
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Seems like the times are close enough that if you ported another pair of cylinders, the winner might reverse. OTOH, if the Mahle is fully broken in and the fast one is the BB kit, then that would make the difference more than it seems on the video.

The BB is 11% faster. That's significant. The OEM is well broken in where as the BB has only had less than a tank through it. Both have stock carbs at this point. I wanted to compare just the P&C for starters. I'll now continue building the 361BB.
 
I didn't check tonight. The OEM usually around 15,100. I don't have much time with the BB but will be in the ballpark of 15,500-15,800.

WOT doesn't really count..... What are they turning in the cut?

the reason i ask is because they really do sound like they are 'screaming'. very high pitched saw sounds!:)

lakes question is a good one though. do you record in-cut rpm?
 
WOT doesn't really count..... What are they turning in the cut?

WOT is only an indicator. Doesn't mean much if you raised the exhaust roof and killed compression to get them. I don't really think RPMs in the wood counts either. The BB is faster because I can push on it harder than the OEM. The OEM would stall if I pushed as much as I am on the BB. It just like the 7900 Slingr built. If I don't really load it down, I saw >13K in the cut with a square ground chain in a different log last night.

the reason i ask is because they really do sound like they are 'screaming'. very high pitched saw sounds!:)

lakes question is a good one though. do you record in-cut rpm?

They are screamin'!:) But nothing out of line with other modded saws.
 
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