Tuning 357XP! How many RPM's?

[Deadman]

I am installing my modded muffler, and plan on richening up the carb by ear, and then taking and putting my Tach on the saw. How many RPM is realistic for a 357XP with only a muffler mod? I'm looking for a safe reliable RPM for daily usage, not competition. I see Huskys website says 14,000 is max rpm, but is that too high? Where should I set the Max Rpm?

Just looking for a tad of extra info before I get started.
Thanks! :greenchainsaw:

 

[SawTroll]

14K is the max allowed, not a goal in itself - if it cuts better and sounds right at lower rpms, by all means keep it there.......

 

[Deadman]

So 13ish?
I'm just trying to double check and be sure its safe.
I know its tuned at 12,900-13,000 right now.

I'll tune it by sound and feel, and then check where its at.

 

[SawTroll]

So 13ish?
I'm just trying to double check and be sure its safe.
I know its tuned at 12,900-13,000 right now.

I'll tune it by sound and feel, and then check where its at.

13K is too low, allmost sertainly......

 

[BlackCatBone]

My stock 357 hits a high of just about 13650, and it is really cutting well.

 

[HiOctane]

Dont be impressed by the numbers only.A good"ear" is still the best.No load,bring the saw to ALMOST losing the four stroke note,you should be right on the target.

 

[Deadman]

Cool, thanks guys.

I'll try it out as soon as the stupid rain stops!

 

[Podaltura]

My muffler mods 357 runs arround 15k, and I havn´t any problem whit the chainsaw.

 

[stihl025]

My muffler mods 357 runs arround 15k, and I havn´t any problem whit the chainsaw.

Yet...

 

[BlackCatBone]

My muffler mods 357 runs arround 15k, and I havn´t any problem whit the chainsaw.

15K? Even with a muffler mod, is it safe to exceed the recommended max rpm on a saw (in general)?

 

[SawTroll]

15K? Even with a muffler mod, is it safe to exceed the recommended max rpm on a saw (in general)?

Husky actually mean it when they say max, unlike Stihl (no +/-) - but I believe there are some leeway anyway.


At least you are eating into the margin of safety.

 

[bogiemsn]

15K? Even with a muffler mod, is it safe to exceed the recommended max rpm on a saw (in general)?

IMHO, whether muffler mod or not its' bad for the saw to exceed max rpms. One of the experts here will correct me if I'm wrong but it's my understanding that that the way top make the saw run at high rpms is to give it a lean mixture, right? Is running the saw too lean hazardous to the saw? You Betcha!

If you get above the engines power band it won't cur any better anyhow. High RPMs without corresponding torque doesn't work.

 

[ispansco]

Have you adjust it at 15.000 rpm a long time ago? :jawdrop:

My 346xp (to muffler mod 45) this adjusted to 14.300 rpm
My 372xp (to muffler mod) this adjusted to 13.300 rpm

:greenchainsaw:

 

[bogiemsn]

I was at a Game of Logging Course over the weekend. It was hosted by a guy who runs a sawmill and saw shop here in central WI. He's been in the business for more than a few years. He noted that Husky (maybe Stihl too, I can't remember) went through a period where they shipped a lot of saws with the revs set too high. Lots of saws got burned up while under warranty so Husky stopped this practice.

 

[SawTroll]

Have you fix it at 15.000 rpm a long time ago? :jawdrop:

My 346xp (to muffler mod 45) this fixed to 14.300 rpm
My 372xp (to muffler mod) this fixed to 13.300 rpm

:greenchainsaw:

I think you really mean adjusted (or set) when you say fix/fixed.........

You never fix the rpms, as they will vary with air density etc at a given setting.

 

[ispansco]

I think you really mean adjusted (or set) when you say fix/fixed.........

You never fix the rpms, as they will vary with air density etc at a given setting.

Sawtroll, you are right, I have big problems with the language.:bang: Thank you for your correction.

 

[BlackCatBone]

IMHO, whether muffler mod or not its' bad for the saw to exceed max rpms. One of the experts here will correct me if I'm wrong but it's my understanding that that the way top make the saw run at high rpms is to give it a lean mixture, right? Is running the saw too lean hazardous to the saw? You Betcha!

If you get above the engines power band it won't cur any better anyhow. High RPMs without corresponding torque doesn't work.

This is pretty much what I'd think too. Exceeding recommended max rpms, to me, means that you are exceeding inertia/rotational balance limits of the piston/crank design. This should result in low torque, excessive wear, and possible catastrophic failure. No matter what adjustments you've made with the air/fuel system, it seems exceeding max rpms is dangerous to me.

I would also reason that something like a muffler mod, or porting would greatly increase your torque at the rpms at the higher end of the recommended range. Is there a consensus?

 

[bogiemsn]

This is pretty much what I'd think too. Exceeding recommended max rpms, to me, means that you are exceeding inertia/rotational balance limits of the piston/crank design. This should result in low torque, excessive wear, and possible catastrophic failure. No matter what adjustments you've made with the air/fuel system, it seems exceeding max rpms is dangerous to me.

I would also reason that something like a muffler mod, or porting would greatly increase your torque at the rpms at the higher end of the recommended range. Is there a consensus?

there is.

 

[Deadman]

I tuned on it, and kinda FEAR the lean top end, so I tuned it and put it on the tach......I was only at 12,900 rpm, and then I leaned it and BINGO it went to 13,800, and cut LIKE CRAZY. I was kinda scared, so I tuned it back to around 13,600. Its a tad weaker, but should be safe. Should I go to 13,800 and be safe, or stay at 13,600 and enjoy a long healthy life?

I had it at 14,100 once, and YOW, that was intense! It sure woke-up with just this muffler mod! The throttle response and everything is much much better.

 

[SWE#Kipp]

My muffler modded 357xpg runs at 14000rpm and do it with a slight burble (4-stroke).
but at 13800 you should be safe ,,, if you got the 4-stroking