Woods ported 372

[Yotaismygame]

Did you raise all the other ports back up? At .050 off the piston that leaves what .090" above the ring? Gettin thin. With the 268 piston I never found the longer intake duration to be a problem. One of the better cutting saws I built with a 268 was at 102ex and 84 intake. Which is what that piston will give you. Not sure on the transfers. They were un-touched. Although I like the 268 piston I've found the stock piston can be made to run just as hot with more compression. Report back. Curious to see how it runs with the intake higher with that piston.

 

[Ronie]

No, I am sorry for stepping on your post. I will shut up and listen.

You can step on my thread/post anytime you want @Duce, I enjoy hearing about anybody's saw. @yotaismyname does make some nice ones .

 

[Ronie]

Did you raise all the other ports back up? At .050 off the piston that leaves what .090" above the ring? Gettin thin. With the 268 piston I never found the longer intake duration to be a problem. One of the better cutting saws I built with a 268 was at 102ex and 84 intake. Which is what that piston will give you. Not sure on the transfers. They were un-touched. Although I like the 268 piston I've found the stock piston can be made to run just as hot with more compression. Report back. Curious to see how it runs with the intake higher with that piston.

I haven't timed it yet but the exhaust and transfers should be almost the same, squish is going from .022 to .019 and the intake will be around 80. I think I had .093 or 4 above the ring.

 

[Yotaismygame]

I haven't time it yet but the exhaust and transfers should be almost the same, squish is going from .022 to .019. I think I had .093 or 4 above the ring.

I had to go back and read. Was thinking you said .030 pop up to start but actually you said .040. So if you took another .010 off the piston did you take the same off the base? That's why I asked about the other ports.

 

[Ronie]

I had to go back and read. Was thinking you said .030 pop up to start but actually you said .040. So if you took another .010 off the piston did you take the same off the base? That's why I asked about the other ports.

No, I had to take .010 off to get the squish to .019

 

[Ronie]

No, I had to take .010 off to get the squish to .019

I have to use a double gasket to get there.

 

[Yotaismygame]

Oh okay! So you probably lowered the compression then right? If you took material out and increased squish.

Edit: or its the same..

 

[Ronie]

Oh okay! So you probably lowered the compression then right? If you took material out and increased squish.

Edit: or its the same..

No, I might not be explaining it right. I went from around a .028 popup and .022 squish, with the 372 piston, to a .050 popup and it now has .019 squish, with the 268 piston.

 

[Yotaismygame]

No, I might not be explaining it right. I went from around a .028 popup and .022 squish to a .050 popup and it now has .019 squish.

Okay so you did lower the jug. Ditched a base gasket and increased the pop up. If I have that right your ports all should have dropped about 2 degrees. 102ex might be just fine.

 

[Ronie]

Okay so you did lower the jug. Ditched a base gasket and increased the pop up. If I have that right your ports all should have dropped about 2 degrees. 102ex might be just fine.

The difference in squish is what would change the ex an tr timing, .003 in this case, or am I thinking about this wrong? When I start putting it back together I'll be timing it and let you know what I got.

 

[Yotaismygame]

No, I might not be explaining it right. I went from around a .028 popup and .022 squish, with the 372 piston, to a .050 popup and it now has .019 squish, with the 268 piston.

If you increased the pop up .022 that would put the new squish at .044. You're saying the new squish is now at .019. Only way to achieve that would be to lower the jug .025. Which would change the port timing roughly 2-3 degrees.

 

[Ronie]

If you increased the pop up .022 that would put the new squish at .044. You're saying the new squish is now at .019. Only way to achieve that would be to lower the jug .025. Which would change the port timing roughly 2-3 degrees.

2 different pistons, the first piston was a 372 popup and the second was a 268 popup

 

[Yotaismygame]

Man i'm all confused now. I thought you were running a 268 piston this whole time.

 

[Ronie]

I said it wrong in the post you quoted, It should have said .028 with the 372 piston
and .050 with the 268 piston

 

[Yotaismygame]

I said it wrong in the post you quoted, It should have said .028 with the 372 piston
and .050 with the 268 piston

ahhh okay. So yes I doubt port timing changed like you were saying. Except the intake since the skirts are different lengths. Did you check for free porting? Those 268 skirts are narrow too. Can barely widen the intake when using one.

 

[Ronie]

ahhh okay. So yes I doubt port timing changed like you were saying. Except the intake since the skirts are different lengths. Did you check for free porting? Those 268 skirts are narrow too. Can barely widen the intake when using one.

I see where I caused the confusion, I said I just cut a .040 popup on a 268 piston but I didn't post anywhere that the saw had a 372 piston to start with and that makes it sound like I just cut more off the piston. No I didn't even think about free porting, hopefully it will be ok.

 

[Ronie]

I'll find out tomorrow about free porting and see what kind of numbers I have.

 

[Ronie]

I just checked for free porting and it's good.

 

[Ronie]

Got it all together and tried it out, I feel like it has a little more torque. I don't think it's any faster in the smaller wood that I have, might be a bit quicker in something larger.

 

[Ronie]

I got it cutting a little faster, wot in the video is right at 14,680 but I turned it back down after the video, afraid I would burn it up running that lean.