Another chainsaw dyno...

[qurotro]

I thought the 572xp is listed at 6hp..And they under rated it? Things are getting interesting.

 

[ayoungtexan]

The stock 572 was rated at 5.8 hp. From what the dyno says, the 572 paper specs are severely underrated

 

[Bigmac]

It’s also only one example, need several dozen 572s to have a good baseline, that particular 572 could be a freak! Or they all could be 7 hp! More data is needed!

 

[dustinwilt68]

I have a 462 and I love it, I have always said I would take it over a 572 that I owned for a 20" bar setup, 24" and up the 572 would definitely be my choice. Stock saw at over 7hp for 70cc is probably the most impressive stock saw I have seen to date on here.

 

[markds2]

View attachment 247191
046 magnum vs 572 both stock

Isn't the 046 tuned a bit rich here? I thought they were meant to be tuned to 13500?

 

[Deets066]

Isn't the 046 tuned a bit rich here? I thought they were meant to be tuned to 13500?

I believe that would only stretch the graph a little, peak power should be close

 

[USMC615]

Damn this thread moves quick...pretty bad ass Deets what your hybrid showed graph-wise!

 

[Red97]

Isn't the 046 tuned a bit rich here? I thought they were meant to be tuned to 13500?

It was probably close to 12.5-13k
Have A couple of parameters on h data box before recording a run to avoid recording a bunch of useless info.

That is a 2hp start limit. Above 10k rpm

So if they didn't make 2+hp above 10k it won't stsrt recording until the saw hits 2hp. Or somewhere close if it is above 10k

I believe that would only stretch the graph a little, peak power should be close

This too.

Peak power has been very consistent regardless of tune. Power above peak looks much better on leaned out runs.

 

[markds2]

It was probably close to 12.5-13k
Have A couple of parameters on h data box before recording a run to avoid recording a bunch of useless info.

That is a 2hp start limit. Above 10k rpm

So if they didn't make 2+hp above 10k it won't stsrt recording until the saw hits 2hp. Or somewhere close if it is above 10k



This too.

Peak power has been very consistent regardless of tune. Power above peak looks much better on leaned out runs.

Very interesting, so leaning out a saw to its theoretical limit doesn't necessarily change how fast it cuts. BTW that 572 is impressive! The 044 dual-port run earlier still doesn't come close.

 

[Bigmac]

Very interesting, so leaning out a saw to its theoretical limit doesn't necessarily change how fast it cuts. BTW that 572 is impressive! The 044 dual-port run earlier still doesn't come close.

No that’s just peak power, will be a lot of situations where you I would cut faster leaned out and above peak power, especially anything smaller

 

[cuinrearview]

No that’s just peak power, will be a lot of situations where you I would cut faster leaned out and above peak power, especially anything smaller

Most people have too much bar for the situation. At least us round wood dicks.

 

[Time's Standing Stihl]

Pretty sure I have at least 6 boxes enroute...

Dyno will be running....

Dang!!!!! Full time Job!

 

[Red97]

Dang!!!!! Full time Job!

That is the goal

 

[jacob j.]

That is the goal

Are you going to continue your side gig of refurbishing cattle prods?

 

[Red97]

Are you going to continue your side gig of refurbishing cattle prods?

Pic of the prod?

 

[RI Chevy]

Poor Cattle...

 

[Duane(Pa)]

Peak power has been very consistent regardless of tune. Power above peak looks much better on leaned out runs.

Farking Gold!!!

 

[Terry Syd]

Power above peak looks much better on leaned out runs.

It's the nature of the carburetor. These little diaphragm carbs don't have an 'air bleed' jet in the high speed circuit to keep the proper fuel mixture after peak power.

I put an air bleed circuit in a Zama to try it and it revved like a motocrosser. Definitely needed a limited coil to keep from blowing it up.

 

[Nutball]

It was probably close to 12.5-13k
Have A couple of parameters on h data box before recording a run to avoid recording a bunch of useless info.

That is a 2hp start limit. Above 10k rpm

So if they didn't make 2+hp above 10k it won't stsrt recording until the saw hits 2hp. Or somewhere close if it is above 10k



This too.

Peak power has been very consistent regardless of tune. Power above peak looks much better on leaned out runs.

Have you tried tuning one on the dyno to find the peak power tune that way?

 

[Redfin]

Pic of the prod?

Side lining is not a denial.