Husky 435 & 440 - same specs but different HP?

[Gomofast]

So Husqvarna shows the 435 rated at 2.2hp and the 440 rated at 2.4hp. But I don't understand how that can possibly be correct. I've looked at the specs and the illustrated parts diagrams. Both saws have the same bore and stroke, and same part numbers for the piston, cylinder, crank, carburetor, and muffler. So how can they have different horsepower ratings?

Perhaps they just tune the carbs a little differently? I suppose it's possible that they set the 435 a little richer and the 440 a little leaner to achieve the slight difference in HP rating. I just received a used 435 and I can say for sure that both the H and L were set a little rich. But I have no idea if it left the factory like that or if the previous owner(s) adjusted it.

Or perhaps both saws really have 2.4hp and they just say the 435 has less to help differentiate the saws.

 

[Lightning Performance]

They can have different bore sizes and different installed piston heights. You have to check each to know where your at with quench and bore size. My 435 is 41mm bore. Fuel or air jets can also be changed and air idol bleeds. Filter media type also matters.

 

[Lightning Performance]

Just remember replacement parts are made to fit many models and may not be OEM as produced from the line run when new. A classed cylinders comes to mind. Maybe 435 have B offerings?

I've never check but I will.

 

[Gomofast]

They can have different bore sizes and different installed piston heights. You have to check each to know where your at with quench and bore size. My 435 is 41mm bore. Fuel or air jets can also be changed and air idol bleeds. Filter media type also matters.

Right, but according to IPLs, they don't. Same piston/cyl and crank assembly - and therefore same bore/stroke and piston height. Also same carb and therefore same jets/etc. Also same air filter and muffler.

 

[Gomofast]

Just remember replacement parts are made to fit many models and may not be OEM as produced from the line run when new. A classed cylinders comes to mind. Maybe 435 have B offerings?

I've never check but I will.

I hadn't considered that possibly the IPLs don't match the factory parts. That would be disappointing but I suppose it's possible.

Not sure what you mean about A/B offerings, but I'm interested.

 

[J D]

Cylinders are different, I would suspect the only difference is the transfers

 

[Gomofast]

Interesting, where did you find these lists? Every IPL I've checked shows a "cylinder assembly" which includes the piston and has the same part number 54735105 for both saws. But your lists here do show different numbers for the piston by itself.

Also, if you Search for either of the 2 part numbers you have shown, all the listings say they fit both saws. And given that the 504735105 P/C kit that I mentioned above is a genuine oem husky part for both saws, you gotta wonder if you were to buy that assembly, which cylinder would you actually be getting?

 

[Lightning Performance]

Right, but according to IPLs, they don't. Same piston/cyl and crank assembly - and therefore same bore/stroke and piston height. Also same carb and therefore same jets/etc. Also same air filter and muffler.

It's never all the same. Things change and get updated.

 

[mountainlake]

Dont get hung up on manufactures specs, it how they cut that matters. Steve

 

[Tomos770]

What goes for 450....goes for 440...435....




Port numbers here are for 450 cylinder...so discard them in your case!

 

[mountainlake]

Heres the way a ported 50cc saw should cut.. Steve

 

[J D]

Interesting, where did you find these lists? Every IPL I've checked shows a "cylinder assembly" which includes the piston and has the same part number 54735105 for both saws. But your lists here do show different numbers for the piston by itself.

Also, if you Search for either of the 2 part numbers you have shown, all the listings say they fit both saws. And given that the 504735105 P/C kit that I mentioned above is a genuine oem husky part for both saws, you gotta wonder if you were to buy that assembly, which cylinder would you actually be getting?

Early IPL (2010-06). It's likely over the years/revisions they've reduced/consolidated the parts where they can. Once the production run is over no one is going to pay the same amount for the de-rated cylinder if they need to replace one so it makes sense to only stock the up spec part

 

[Gomofast]

Early IPL (2010-06). It's likely over the years/revisions they've reduced/consolidated the parts where they can. Once the production run is over no one is going to pay the same amount for the de-rated cylinder if they need to replace one so it makes sense to only stock the up spec part

Makes sense I guess.

 

[Agrarian]

For these two models, isn't this one of those cylinders that is the same but they have different transfer plates?