Part Three: The Transfer Ports

[huskihl]

Mufflers are overrated..

Very...

 

[Deets066]

Probly stock on an 066 lol.

Well, kinda... but still not stock

 

[Hedgerow]

Very...

View attachment 139019

They don't make corn cans just for carrying corn..

 

[Redfin]

 

[huskihl]

View attachment 139027

Bingooooo

 

[Billy Currie]

OK, I have read this thread and I have not seen anyone cover finger ports verses external transfers. Is one more beneficial than the other?

 

[Adirondackstihl]

OK, I have read this thread and I have not seen anyone cover finger ports verses external transfers. Is one more beneficial than the other?

What fuel ya runnin?

 

[Wonkydonkey]

I'm not reading it all again today, ant got the time....but what-about boost, bridge and finger ports, as it’s come up.

Normal fuel for me,

I'll have to read this Fred again. Cos I’m still a newb at this more powa modin stuffs

 

[Mastermind]

OK, I have read this thread and I have not seen anyone cover finger ports verses external transfers. Is one more beneficial than the other?

Finger ports ain't really gonna make a huge difference......but they work best on large displacement engines. They really don't have enough area in smaller bores. They can help aid in directing the charge somewhat. Plus, they are akin to an open port, in that they pick up heat from the piston.

External transfers can really make a big difference. But remember that the rear bolts holding the jug down can get in the way....and if it's a two piece jug, tubes to run the head bolts through have to be added....

Everything is a compromise.....

 

[Mastermind]

I'm not reading it all again today, ant got the time....but what-about boost, bridge and finger ports, as it’s come up.

Normal fuel for me,

I'll have to read this Fred again. Cos I’m still a newb at this more powa modin stuffs

Anything that adds transfer area has to make some difference. But once additional area is added....will the engine have enough carb?

Everything works together to the point that in most cases....at least for working saws, just using what the factory gave you makes the best all around machine.

 

[Billy Currie]

Wow, that was great! Excellent explanation!

I run E-85 and nitro some, methanol and nitro, and gasoline. Depends on what saw I grab. I want to go all methanol and nitro in everything eventually.

 

[Wonkydonkey]

Yes I agree. It all makes sense, in a jumbled jigsaw puzzle way

I’ve been reading a few old threads from around 3 to a 8 yrs ago on AS. It’s easy to read but like any algebra equation, when to try to put it into your saw.... does it will it make a better answer to what it’s putting out all ready... well my probs is I buy knackered saws and play with China pots. So there’s gains to be had. But the equation is still a jigsaw.

Right now I’ve 2 200t with China pots. I could do with stock numbers to see if China has done a good job or how can I make it better.

Btw. I just put it together and made sure they ran and added a bit of timing adv

But I’ve also got a 260 that’s got a China pot and Some boost ports with a little trans enlargement and that’s g9t a whole lot more torque since.

I have the upmost admiration for all these porting guys and there attention to detail.

 

[MustangMike]

I'm no expert, but I've had some good results adding small bridge ports to some of the Asian 440 BB jugs. My theory is that is provides a bit of addl direction, that helps evacuate the spent gas, w/o being large enough to kill flow speed of the transfer.

That said, my MOFO ported 460 (has an 046 D jug) has larger bridge ports, and that saw screams! Al says he prefers the Hemi head 460 jugs, but I don't think I've run a stronger one than mine. Note: My MOFO 460 really woke up with a HD-50 (461) carb. It is my only saw that liked that carb!

If anyone has a logical explanation, I'd love to hear it. As for me, I just try different things and try to do what works!

 

[RI Chevy]

HD50 is a smaller carb Mike. Smaller jets.
Not sure how your saw will go faster with a carb with smaller jets.
AND don't make me post up vids of the 460 runoff up in NYGTG. Mine, yours and Dave's.
LMAO.

 

[huskyboy]

Post the videos lol

 

[MustangMike]

From which NY GTG Jeff, before or after a did the carb change???

Don't worry, it will be at the one in the Spring.

 

[RI Chevy]

Last year.

 

[MustangMike]

I'm not specifically recalling it, but I do remember a few of my saws got rocked at that one, not all the wood was clean.

 

[drf256]

I’ve personally held, in my own hands, HD50 carbs with either a 58 and an 70 jet. It’s very strange.

The 70 jet is rare on the HD50. The one I saw was likely an enigma.

It’s the midrange circuit of the HD50 that’s supposed to make it shine.

Saws that pull more air through a carb, as in larger displacement saws with the same carb bores, usually need a smaller jet. More air pulls more fuel out of the same Venturi. Slower air moving doesn’t allow enough fuel siphoning.

When I put an 044 carb on an 026, I drill the jet out to almost a 76-78. I know it sounds counterintuitive.

The best way to see if a saw needs a bigger jet (IMHO) is to see how it runs. In a medium ambient temp, let’s say 60*F, see where your H needle is and whether or not saw holds high tune. If your H is out more than 1.25 turns, you probably need a bigger jet.

 

[Mastermind]

I’ve personally held, in my own hands, HD50 carbs with either a 58 and an 70 jet. It’s very strange.

The 70 jet is rare on the HD50. The one I saw was likely an enigma.

It’s the midrange circuit of the HD50 that’s supposed to make it shine.

Saws that pull more air through a carb, as in larger displacement saws with the same carb bores, usually need a smaller jet. More air pulls more fuel out of the same Venturi. Slower air moving doesn’t allow enough fuel siphoning.

When I put an 044 carb on an 026, I drill the jet out to almost a 76-78. I know it sounds counterintuitive.

The best way to see if a saw needs a bigger jet (IMHO) is to see how it runs. In a medium ambient temp, let’s say 60*F, see where your H needle is and whether or not saw holds high tune. If your H is out more than 1.25 turns, you probably need a bigger jet.

Excellent post.