Modding a Poulan Pro 475

[bryanr2]

subbed.

 

[mdavlee]

Looks pretty good there. A little rich for best cookie times.

 

[Deets066]

That's nice clean work in the uppers.

Cool saw to build

 

[GoBigBlue1984]

Thank you Deets!

 

[Deets066]

With the shorter skirts of the 272 and an intake at 85, I would be lookin for a way to take up some case volume before I added fingers

 

[Mastermind]

With the shorter skirts of the 272 and an intake at 85, I would be lookin for a way to take up some case volume before I added fingers

I'd agree.....

Not a fan of a long intake duration.

 

[GoBigBlue1984]

With the shorter skirts of the 272 and an intake at 85, I would be lookin for a way to take up some case volume before I added fingers

Go on Deets. This is an open build. I'm open to suggestions and appreciate any and all input.

 

[GoBigBlue1984]

I'd agree.....

Not a fan of a long intake duration.

Do you care to elaborate?

 

[Deets066]

I don't think the intake is too bad seeing that it was only machined to be that low and not ground to be lower.

Still I bet you'd gain from some sort of crank stuffer

 

[Deets066]

Fingers would be sweet with a full circle crank here

 

[Deets066]

Know any good machinists Brett?

 

[Mastermind]

Do you care to elaborate?

I'll try.

Too much intake hurts throttle response, idle and transition quality, and creates spitback. It also hurts primary compression.

What Deets is saying about stuffers is dead on in my humble opinion. With a reduction in case volume, you might get away with the long intake duration.

On the other hand, it could make the spitback aspect more pronounced.

A velocity stack would help that though.

 

[Mastermind]

Know any good machinists Brett?

Bingo.

 

[Deets066]

@awol

 

[GoBigBlue1984]

I'll try.

Too much intake hurts throttle response, idle and transition quality, and creates spitback. It also hurts primary compression.

What Deets is saying about stuffers is dead on in my humble opinion. With a reduction in case volume, you might get away with the long intake duration.

On the other hand, it could make the spitback aspect more pronounced.

A velocity stack would help that though.

I figured going in that idle would be wonky. It has been somewhat. I sent Joey a video of it before I put it in any wood (also before I did a little fine-tuning to the carb.) It would spool up very well and take a little longer than normal to come back. Even then, idle was slightly higher for 10 seconds before returning to normal range. But I may be able to correct that with a little more carb adjustment time. Maybe not. I like where Deets is going with a full circle crank. I also like the stack idea with a custom elbow.
This is not good stuff, this is great stuff. I freakin love it!!!!!!

More to come!!

Thank you Deeter and Randy.

 

[Mastermind]

What do you guys think about a series of threads dedicated to one aspect of the engine?

Like a thread on exhaust height, port size, shape, effects, etc....

Another on intake.....then transfers, compression, pop-up pistons, etc.

 

[Mastermind]

I figured going in that idle would be wonky. It has been somewhat. I sent Joey a video of it before I put it in any wood (also before I did a little fine-tuning to the carb.) It would spool up very well and take a little longer than normal to come back. Even then, idle was slightly higher for 10 seconds before returning to normal range. But I may be able to correct that with a little more carb adjustment time. Maybe not. I like where Deets is going with a full circle crank. I also like the stack idea with a custom elbow.
This is not good stuff, this is great stuff. I freakin love it!!!!!!

More to come!!

Thank you Deeter and Randy.

Any chance of using 576XP stuffers on other cranks?

 

[Deets066]

Any chance of using 576XP stuffers on other cranks?

Is the 576 a full circle like the 562?

 

[Adirondackstihl]

What do you guys think about a series of threads dedicated to one aspect of the engine?

Like a thread on exhaust height, port size, shape, effects, etc....

Another on intake.....then transfers, compression, pop-up pistons, etc.

^ I rike dis idea

 

[Sty57]

Is the 576 a full circle like the 562?

As far as I know the 357, 550 and 562 are the only ones.

I take that back....I just looked at the IPL the 570 and 576 show stuffers too.