circle crank ms660

[Keith Gandy]

J,

My little brain thinks you should raise the intake to 75 and do nothing else first.

You've suddenly got less case volume, so your ratio has changed. You can't overstuff the case, it's only gonna fill so much. Too much intake will just cause loads of blowback and less case compression. You should have a smaller volume higher velocity transfer charge.

So you should need LESS intake duration. You should need less everything duration.

But your saw should rev higher than a similar 066. You created a smaller motor that should spin higher and the torque peak should be at a higher rpm. Think about the changes you like when you put a 66 jug on a 64, or a 46 jug on a 44. The changes those hybrids like should apply here. You created a hybrid with the same parts.

That's how I see it, and I may be 100% wrong. Try it first and see what happens. You can always grind some JB weld out.

What if he opened the lowers? Would that be counterproductive of what the fullcrank was for?

 

[Keith Gandy]

Thinkin on what Al said what if u opened the lower transfer lip toward crankcase and raised the upper transfer height for some rpm and leave the exhaust where it is to keep compression?

 

[drf256]

What if he opened the lowers? Would that be counterproductive of what the fullcrank was for?

Well....

Depends on what he wants. The circle crank gives him a lot of latitude. He can hog out the lowers without the detriment of lowering case pressure. He could make a bigger/wider transfer circuit without affecting pressure as much.

It depends on intended purpose.

He just got a lot more options.

 

[drf256]

Thinkin on what Al said what if u opened the lower transfer lip toward crankcase and raised the upper transfer height for some rpm and leave the exhaust where it is to keep compression?

I used to open mine until Randy schooled me on it.

The crank throws, and now the entire circle, covers the area around and below the lower lip. It's also now .120 lower than before, so it's really covered.

 

[Deets066]

Knock the lower lip off, square up the uppers and maybe raise a degree or two. Then I'd run it, next I would epoxy the intake to around 75 or 76 like doc said, and run it. You can always take it out.

 

[Keith Gandy]

I used to open mine until Randy schooled me on it.

The crank throws, and now the entire circle, covers the area around and below the lower lip. It's also now .120 lower than before, so it's really covered.

Sounds like it may turn into a hyper hybrid? Interesting! I wanna see where he goes and how she comes out

 

[Keith Gandy]

Knock the lower lip off, square up the uppers and maybe raise a degree or two. Then I'd run it, next I would epoxy the intake to around 75 or 76 like doc said, and run it. You can always take it out.

Thats kinda the way I see it too deets after thinkin about what Al said but Jason has options here and this should be intetesting. Is this fullcircle the same effect as the crank stuffers in a 550xp?

 

[Deets066]

Sounds like it may turn into a hyper hybrid? Interesting! Im wanna see where he goes and how she comes out

Me too, Get you A$$ outta bed Stratton!

 

[Deets066]

Thats kinda the way I see it too deets after thinkin about what Al said but Jason has options here and this should be intetesting. Is this fullcircle the same effect as the crank stuffers in a 550xp?

Similar, but probly don't take up as much room as the full circle

 

[drf256]

Thats kinda the way I see it too deets after thinkin about what Al said but Jason has options here and this should be intetesting. Is this fullcircle the same effect as the crank stuffers in a 550xp?

It should be like super crank stuffers. Whatever they do, this should do it more.

I'm shooting from the hip from what I've studied. So this is theory, not proof.

Maybe @tree monkey will opine here.

 

[drf256]

This crap makes me wonder about going both ways, lol...

If I ever get my 44/46 hybrid off the garage floor, I wonder what turning the crank down a bit will do?

Increase case volume closer to a 46 with a lighter crank. Maybe even create knife edges.

 

[Keith Gandy]

It should be like super crank stuffers. Whatever they do, this should do it more.

I'm shooting from the hip from what I've studied. So this is theory, not proof.

Maybe @tree monkey will opine here.

It makes sense though

 

[Keith Gandy]

What if he epoxied the intake floor up and raised the roof and widened for time/area without the longer duration?

 

[Deets066]

This crap makes me wonder about going both ways, lol...

If I ever get my 44/46 hybrid off the garage floor, I wonder what turning the crank down a bit will do?

Increase case volume closer to a 46 with a lighter crank. Maybe even create knife edges.

There isn't as much extra velocity to play with as you think. I bet turning your crank down would make a turd for torque. Snappy limber at best.

 

[Deets066]

What if he epoxied the intake floor up and raised the roof and add widened for time/area without the longer duration?

He can widen a mile on the intake with the 288 piston, that is where he could get his "time"

 

[Keith Gandy]

This crap makes me wonder about going both ways, lol...

If I ever get my 44/46 hybrid off the garage floor, I wonder what turning the crank down a bit will do?

Increase case volume closer to a 46 with a lighter crank. Maybe even create knife edges.

Now thats an idea!! The hybrid lacks torque imo

 

[Keith Gandy]

There isn't as much extra velocity to play with as you think. I bet turning your crank down would make a turd for torque. Snappy limber at best.

Guess im thinkin opposite on that for some reason

 

[Keith Gandy]

He can widen a mile on the intake with the 288 piston, that is where he could get his "time"

How does area/widening vs longer duration work on a saw in the intake?

 

[drf256]

What if he epoxied the intake floor up and raised the roof and widened for time/area without the longer duration?

He can't raise the roof. If you see above, he had to drop it that much so the ring stayed tucked under it.

 

[drf256]

Guess im thinkin opposite on that for some reason

I am too.

A heavy rotating assembly stores kinetic energy that's released in the first second the bar hits the wood. Then it's gone. A lighter assembly will lack that, but should spool up faster and have more rpm.