Another chainsaw dyno...

[Bigmac]

If I remember right a ported 064 was 9 - 9.5hp at the ct gtg a couple years ago on the dyno. Should be interesting to see what some of the bigger 90cc do.

I just remember the old dyno threads that the ported 660s were around 8 hp

 

[Sawrain]

I wouldn’t have thought that an open muffler would have an horrendously narrowed torque band compared to stock, of course two strokes with properly timed/tuned expansion pipes perform much worse without them, but we don’t have those Gains to lose.

I have seen dirt bikes run with no exhaust, the result was seizure, twice when I was younger anyway.

Love this dyno, excited to see the number produced over the next few years.

 

[Red97]

Hopefully run thumper next weekend. Broke down and ordered a 404 sprocket. As this echo dosent have a rim available. Just 404 spur.

 

[huskyboy]

I just remember the old dyno threads that the ported 660s were around 8 hp

Yep usually a 064 or older 066 run better than a 660.

 

[Bigmac]

Yep usually a 064 or older 066 run better than a 660.

Yes I have heard that, especially stock, I thought one ported they were a little closer?

 

[Lee H]

Hopefully run thumper next weekend. Broke down and ordered a 404 sprocket. As this echo dosent have a rim available. Just 404 spur.

View attachment 240059

Those are nice saws with plenty of power, Curious as to the power ratings you come up with.

 

[huskyboy]

Yes I have heard that, especially stock, I thought one supported they were a little closer?

Ported 660

064 not ported with basic mods (bgd/ta/muff mod)

One second difference in cut times same chain. Both OEM saws.

 

[Red97]

Those are nice saws with plenty of power, Curious as to the power ratings you come up with.

This one is going to get ported and try to fit a 66mm top end... 150cc... if that works may take it to 70mm just because.

 

[TreeLife]

This one is going to get ported and try to fit a 66mm top end... 150cc... if that works may take it to 70mm just because.

You're a mad scientist, Joe. I love it. Never stop!

 

[Lee H]

This one is going to get ported and try to fit a 66mm top end... 150cc... if that works may take it to 70mm just because.

I like the way you think. Anything is possible.

 

[Wolverine]

I am super curious if there’s any 10 horse worksaws is out there! I’m also super curious what some of the better 395’s are putting out

#metoo

@7 hp stock, 30-40% gains should be right there. Dammit. I wanna send it! How much would it be from 17325 to Joe?

 

[Red97]

#metoo

@7 hp stock, 30-40% gains should be right there. Dammit. I wanna send it! How much would it be from 17325 to Joe?

49251

 

[Bigmac]

#metoo

@7 hp stock, 30-40% gains should be right there. Dammit. I wanna send it! How much would it be from 17325 to Joe?

This is all I want to hear

 

[p61 western]

This is all I want to hearView attachment 240081

Hold my beer...

 

[ucm931]

Getting out of the super heavyweight division for a minute.....I'd like to see a matchup of 545 vs 550 vs 545/562 hybrid vs 550/562 hybrid. Stock and ported for all. Be interesting to see the progression in graphs for each.

Edited to fix a dee dee dee moment.

 

[drf256]

If I remember right a ported 064 was 9 - 9.5hp at the ct gtg a couple years ago on the dyno. Should be interesting to see what some of the bigger 90cc do.

That was the JMS saw. Hit 9.5-10hp. Curve was peaky.

I have the duplicate jug here on my bench. Off of my “Unicorn”. It even has a giant fućk you crack in the plating below the intake port. Only the best for his “friends”.

 

[drf256]

@blsnelling sent one of the most impressive saws there. A clean 340 he put a ported 346 jug on.

That saw made a clean 5hp with a near perfect curve IIRC. Well mannered, idled well, the whole shebang.

My MMWS 066 made 8-8.5 HP, but the curve had more area under it than the JMS saw. It was pretty much dead flat-a true work saw. Bill said “that’s a Randy saw”. Peak HP ain’t what it’s all about.

 

[rogue60]

Would be interesting to see what a 100% stock ms661 puts out.

 

[Red97]

I think I have most everything figured out, other than the software/graphs.

It is stihl the same data from the box, so a video can be used to make the graph if needed.

The plan is to use this rather expensive tool for my saw business.

I will be selling "dyno" service to anyone who is interested.

Price structure
You send me the saw, tell me what rpm to set it max, I'll dial in the low/idle

60$ + return shipping price
You get 3 pulls, with a video recording of the data. Printout/graph/chart if everything else works out.

Or 50$ per hour for testing trial/error muffler mods, timing advance, carbs, even swapping cylinders etc.

Whatever the results are are between me and the customer. If you as a customer decide to share the findings, that is your choice.

I don't feel it is my place to share the results that someone else paid for.

I do plan to keep copies of the data, so it won't get mixed up.

I would love nothing more than to sit here and test saws till the sun goes down.

But can't do so without compensation, sooner or later the dyno is going to need parts/service etc.

I have to find/draft up a liability release form.

Just in case anything happens to the saw during a run.

Figure I might as well post the pricing structure/format for all to see.

I am glad everyone is enjoying following along.

I will still throw out some bones for ya to gnaw on. lol

I would love nothing more than to get an 8-9hp 70cc worksaw to smoke my builds. Light a fire to make mine even stronger.

If guys want to pool resources/saws and do a community testing, aim sure something like that could be arranged.


I would love to host some type of build off someday.

Plan to host a dyno day sometime this summer. May see lots of interesting numbers then.

 

[mgr1]

Curious what torque does when you extend the distance between exhaust flange and the muffler itself.