372 X-torq Mod Discussion Final Woods Port Video Posted

[XP_Slinger]

Like I said earlier, I've done them both ways. I don't alter the intake tract at all except for the air filter base. The only difference between gutted and not gutted is fuel usage.

So at the very least I got some extra oil on the wrist pin sides of the piston. I'll take it.

 

[XP_Slinger]

Yup, I lied. Phase 2 is now planned. I think I have a problem

 

[smokey7]

Is the idea that you are looking to get a 100% pure charge of mix and air in the cyl by doing the gut? I wonder how this is acutely affecting the engine? I have seen a stout fast 241 I think and I wonder on the life of the saw what it would do to it?

 

[XP_Slinger]

Is the idea that you are looking to get a 100% pure charge of mix and air in the cyl by doing the gut? I wonder how this is acutely affecting the engine? I have seen a stout fast 241 I think and I wonder on the life of the saw what it would do to it?

Good question. The short answer is yes. More fuel in the main intake and maybe a small charge making it to the stratos.

I have thought about this mod for a long time and I really don't see where it would hurt the saw. A $900 saw is no throw away tool for me so I put a lot of thought into deciding whether or not to perform this alteration. Please keep in mind I am not, nor am I claiming to be an expert in the field.

One benefit I see in sending fuel through the strato ports is getting some extra oil on the wrist pin sides of the piston. This mod has also tamed the idle on my saw. It was "surgy" before, and yes it was properly tuned. Now as you can hear in the video it comes down to a nice consistent idle after every cut.

By and large I am experimenting based on a few other sources and so far I am pleased with the results. I am not trying to persuade others to follow suite with what I'm doing. Rather, I am just sharing some info and enjoying conversations with folks such as yourself.

 

[smokey7]

Good stuff, partly what is making me wonder is I have seen first hand the change in life span from some crazy porting PJS did on some cylinders years ago. Let me say they are absolutely the most nasty setup I have ever ran. Only problem is I can only get about 20 hrs out of a crank before they start coming apart. It's not over revving either it's just way stronger on acceleration that it stresses the crank that much bond the crank just goes out.

 

[XP_Slinger]

Good stuff, partly what is making me wonder is I have seen first hand the change in life span from some crazy porting PJS did on some cylinders years ago. Let me say they are absolutely the most nasty setup I have ever ran. Only problem is I can only get about 20 hrs out of a crank before they start coming apart. It's not over revving either it's just way stronger on acceleration that it stresses the crank that much bond the crank just goes out.

Ouch! Hopefully I don't run into that with my "shade tree" mods. You are absolutely correct that mods at some point shorten the life span of an engine. That's why I'm staying on the milder side of things in that I am at this point trying to make the engine breath more efficient without making it a screaming time bomb. I think of it like a small block chevy in a way. If you've ever messed with one, you know that bolting on an intake, a set of heads, a a good carb, a mild cam and a higher flow exhaust doesn't hurt longevity at all. It simply gets the engine breathing better and unleashes power left un tapped by the factory. The Husqvarna engineers could certainly build a better tree eating power house than I could ever dream to, but they have to deal with restrictions imposed on them by agencies such as the EPA in their designs.

 

[Keith Gandy]

Good question. The short answer is yes. More fuel in the main intake and maybe a small charge making it to the stratos.

I have thought about this mod for a long time and I really don't see where it would hurt the saw. A $900 saw is no throw away tool for me so I put a lot of thought into deciding whether or not to perform this alteration. Please keep in mind I am not, nor am I claiming to be an expert in the field.

One benefit I see in sending fuel through the strato ports is getting some extra oil on the wrist pin sides of the piston. This mod has also tamed the idle on my saw. It was "surgy" before, and yes it was properly tuned. Now as you can hear in the video it comes down to a nice consistent idle after every cut.

By and large I am experimenting based on a few other sources and so far I am pleased with the results. I am not trying to persuade others to follow suite with what I'm doing. Rather, I am just sharing some info and enjoying conversations with folks such as yourself.

Fuel cools the engine right? More fuel would cool more wouldnt it?

 

[Keith Gandy]

Hopefully everybody is feeding these ported saw lowerends 32:1?

 

[XP_Slinger]

Fuel cools the engine right? More fuel would cool more wouldnt it?

You are correct. Another added benefit of optimizing these little engines. I deleted my base gasket which bumped compression from 150 psi to 180 psi which generates more heat. Getting a bigger charge in the cylinder helps compensate for this, and a muffler mod also helps get the heat out faster as well.

 

[Keith Gandy]

You are correct. Another added benefit of optimizing these little engines. I deleted my base gasket which bumped compression from 150 psi to 180 psi which generates mores heat. Getting a bigger charge in the cylinder helps compensate for this, and a muffler mod also helps get the heat out faster.

I believe a ported saw will last as long as a factory saw but with the added compression I think the bottomend requires more oil

 

[XP_Slinger]

Hopefully everybody is feeding these ported saw lowerends 32:1?

I run all my saws at 40:1 with premium synthetic oil. Another highly debatable topic based on personal preference where everyone is right...lol

 

[Keith Gandy]

On reg carb saws I do 32to1 but mtronic/autotune I do 40t1

 

[Keith Gandy]

I think the autotune/mtronics saws have a limit to what they can handle on fuel mix and especially one thats strato gutted. They just dont seem to run as good at 32to1 for me

 

[XP_Slinger]

I believe a ported saw will last as long as a factory saw but with the added compression I think the bottomend requires more oil

I agree. A woods ported saw isn't going to have the longevity characteristics of a race saw. Big difference in everyday work and 6 seconds of racing. The proof is in the saws run everyday by members here that have been worked over by the outstanding builders we have here. It's the difference between building and engine to pull a trailer vs race a 1/4 mile.

 

[XP_Slinger]

I think the autotune/mtronics saws have a limit to what they can handle on fuel mix and especially one thats strato gutted. They just dont seem to run as good at 32to1 for me

I have zero experience with AT saws so I cannot offer an opinion. They work, that's for sure, but for now all my saws are normal carbs.

 

[RIDE-RED 350r]

Kind of off-topic but not completely: I have read more than a few oil and ratio threads in my time on forums about my hobbies and interests, everything from saws to 250r's...

In the course of weeding through the hype and BS claims that brand "X" can be run at 100:1 safely and third hand accounts of miracle stories, I keep coming back to one common thing suggested by people who seem to know.. And have seen this common point stated in well tested and documented trials conducted by well financed race teams.. And that is the ratio of 32:1. I have even seen dyno testing write-ups that concluded that the ratio of 32:1 yielded the best performance in terms of net HP and torque output...I run castor based oil at 32:1 in my 250r's based on alot of research and learning along with the conditions in which my R's are run and the way the engines are built.

My saws I run at the manufacturers recommended 50:1. But that may change if XP_Slinger and I keep pushing our mods a little bit further.

Bottom line is, all of the moving parts in the engine count on that oil for lubrication. The better you keep it lubricated, the longer those moving parts will last, generally speaking. Sure you can get away with stratospherically high fuel to oil ratios for a time, and maybe you don't even have a catastrophic failure.. But I well never believe that the engine will last as long as it would on a more "normal" ratio. Conversely, I don't think we should go to the other extreme and drown the engine in oil at ratios of 16:1 and lower. Between 30:1 and 40:1 seems to be the sweet spot that most people who "know" run, particularly 32:1.

I don't think XP_Slinger can go wrong in changing things a bit to allow for better fuel delivery and lubrication of the engine internals.

Just have to remember, more oil in the mix (numerically lower ratio) means more oil present/occupying space in the fuel mix which translates to less fuel. Which in turn means you will need to enrich your jetting a smidge from where it was tuned on 50:1.

 

[XP_Slinger]

Good post Joe

 

[mdavlee]

I wouldn't run 50:1 in a stock husky. There's been too many crank bearing failures in them.

 

[smokey7]

It is a bit of a hot button in any forum I've seen with oil threads. I do enjoy reading them tho. So I decided to try some cray stuff awhile ago with the saber. I have a strato poulan and a poulan leaf blower both running 100:1 as a torture test. So far after several gallons of gas I have no complaints with the oils protection. Actually am quite impressed and really enjoy the quick warm ups and no smoke. Also the engines seems to be very well lubed still. I do know I wouldn't test it like this on a item I liked. On any of my heavily modded pwc I will only run 32:1-40:1 depending on my plans and type of riding for that day.

 

[XP_Slinger]

Well, I raised my transfers 5°, widened the exhaust and did some more work on the carb side of the intake. Didn't get the wow I was hoping for. Next step is raising the exhaust. How much? Not sure yet but my transfer change took me from 21° of blowdown to 16°. Current timing is 100 / 116 / 77.

My brother (Ride-Red350R) ported his XPW at the same time and he got the "Holy Frick!" of the day. Man did that saw come to life and run like a rabid beast. XPW - 1, X-TORQ - 0 on the day