Nik's Poulan Thread

[redunshee]

Since the final outlet is much smaller I don't think it would make much difference. Perhaps it is designed as a choke point to provide back pressure

Not so sure. If the purpose of porting a saw is to widen the exhaust port for better flow it would seem logical that you would want as much unrestricted muffler flow possible. Most of the restriction would occur at the outlet so I would want the muffler inlet to be as large as the exhaust port.

 

[redunshee]

I think when you port a saw the idea is to get more air thru it, so you can mix it with fuel and make more power.
Reverse exhaust pressure waves help cram the escaping mix back into the combustion chamber. Making more power. Perhaps the factory engineers sized the 4200 exhaust flange to reflect the pressure wave back to the cylinder. I dunno

I see what ur saying but why is the exhaust port widened when a saw is ported? Wouldn't this be counter to the reverse exhaust pressure waves? Scientifically I really don't know what I'm saying. Just tossing things out.

 

[3000 FPS]

I think when you port a saw the idea is to get more air thru it, so you can mix it with fuel and make more power.
Reverse exhaust pressure waves help cram the escaping mix back into the combustion chamber. Making more power. Perhaps the factory engineers sized the 4200 exhaust flange to reflect the pressure wave back to the cylinder. I dunno

I am afraid that does not hold true with 2 cycle engines that have ports that are controlled by reed valves and the piston.
When you match the exhaust port on the cylinder to the muffler it is called port matching and it does help with air flow and will increase the performance of the engine. I always use the gasket with the bolts thru it to get them both the same.

There has been some very good testing on muffler modding and it has been found that the better the flo thru the muffler the better the performance of the engine. This has nothing to do with tuned pipes which use a resonant wave to gain performance.

 

[Modifiedmark]

Yeah Poulan really used to worry about back pressure.

 

[redunshee]

Yeah Poulan really used to worry about back pressure. View attachment 332988

Man you must be working hard. Haven't heard from you in a dogs age!

 

[PogoInTheWoods]

just looking at that made my ears bleed!.....

Ya had to be there!

​

 

[Modifiedmark]

I'm still surprised this rare bird hasn't been snatched up yet. Price is good for what it is.http://m.ebay.com/itm/141170307152?nav=WATCHING_ACTIVE

 

[Modifiedmark]

Watch ya say?

Ya had to be there!

​

 

[Warped5]

I'm still surprised this rare bird hasn't been snatched up yet. Price is good for what it is.http://m.ebay.com/itm/141170307152?nav=WATCHING_ACTIVE

Seller is member teddy.scout here ... Matt's a good guy.

 

[redunshee]

I'm still surprised this rare bird hasn't been snatched up yet. Price is good for what it is.http://m.ebay.com/itm/141170307152?nav=WATCHING_ACTIVE

Saw that but outa my style.

 

[PogoInTheWoods]

Watch ya say?

YA HAD TO BE THERE!

​

 

[jerry quinn]

I am going to look at a 4200. Anything I should look out for. In the eighties there was a poulan dealer five miles from my house. It seems a few were sold, I have run across three in two days.

 

[redunshee]

The usual things. Condition of P&C. Likely need to remove muffler, if possible. If you have a compression gauge I'd check comp. general condition of the saw. Does it look beaten or in fairly good shape. Anything missing? Check spark as parts are almost nonexistent.

 

[jerry quinn]

The usual things. Condition of P&C. Likely need to remove muffler, if possible. If you have a compression gauge I'd check comp. general condition of the saw. Does it look beaten or in fairly good shape. Anything missing? Check spark as parts are almost nonexistent.

The guy wants to sell it because he can`t find a air filter for it. So he is using it without a filter.. I have to save it.

 

[motti]

The guy wants to sell it because he can`t find a air filter for it. So he is using it without a filter.. I have to save it.

Good for you! Most any of those Poulans I'd "save", too. Even if was totally beat and not worth fixing - I'd clean it up and paint it like brand new and hang it on the wall. Can't get more respect than that.

 

[Acornhill]

picked these up off the bay, not sure anyone even saw the covers.

 

[Acornhill]

here is most of my NOS stock, and some sleeping mega HP.

 

[jerry quinn]

I spy a 3400 series clutch cover, I haven`t found a good one yet.

 

[Kostas]

Are the intake parts of a 4620 interchangeable with the ones from a Husqvarna 142?

View attachment 332291

142 left and 4620 right.

 

[redunshee]

Nice haul. Was it all one purchase?