Torque, RPMs, Porting...My Philosophy

[chadihman]

Here's the 461 vs 660 stock with 8+ tanks through the 660

 

[chadihman]

Here's the 461 vs the 660 DP Finally the 660 has a good edge on the 461

 

[chadihman]

Finally the one were interested in. This is the ported 361 vs stock 461 vs stock 660. Notice how the 361 has a more hp at 12000 than the 461 and 660 and how level the line looks compaerd to the others.

 

[chadihman]

I'll have some graphs of the ported 361 vs a stock 361 vs a mm 361 maybe by the weekend along with Randy's ported 261 cm vs my stock 261 cm.

 

[HuskStihl]

Awesome chad! I totally stand corrected on the DP 660.
Nice power curve on the 361 Brad. Dyno's are fun.

 

[blsnelling]

Finally the one were interested in. This is the ported 361 vs stock 461 vs stock 660. Notice how the 361 has a more hp at 12000 than the 461 and 660 and how level the line looks compaerd to the others.

That is awesome...exactly the point I'm trying to make in this thread. Notice how the lower RPM curve is just as flat as the stock 461 & 660, but the peak is moved up 1,500-2,000 RPMs, and doesn't fall off nearly as quickly at high RPMs. It's making > 4HP from 7,500 RPMs to well above 12,000 RPMs. Who wouldn't want a powerband like that?!

 

[blsnelling]

BTW Chad, thanks for all your hard work. I had no idea you had bought Nik's saw until you told me.

 

[blsnelling]

Anyone have one of my 461s or strato gutted 261s that they'd be willing to send to Chad? I'd be willing to pay shipping both ways.

 

[MustangMike]

Awesome information Chad, thanks for your dedication and perseverance.

What a difference that dual port makes on the 660, I'd love to see similar tests on the 044.

It would also be great to know what RPMs that ported 361 holds in the cut (figure average hardwood with a 20" bar).

 

[Haywire Haywood]

Very nice Chad. Thanks for the great work.

 

[Time's Standing Stihl]

Awesome info Chad! Thanks for all the time you have been putting in for us. I was a bit skeptical at first reading all the info, now that the graphs are out, I'm a believer with your dyno.

Thanks again man

 

[porsche965]

This testing takes time, and thanks for taking yours and sharing with all of us on AS.

 

[Mike from Maine]

Here's the 461 vs the 660 DP Finally the 660 has a good edge on the 461

Thanks for taking the time to do the testing... But I think the most interesting will be seeing the difference between a stock, muffler modded and ported saw of the same model.

Using your data points I made a chart that makes the 660dp look a little better (it needs all the help it can get)
Lies, damn lies and statistics

 

[old-cat]

Well Chad, everybody with a modded saw is going to want some run time on your Magik machine now!!

 

[old-cat]

Anyone have one of my 461s or strato gutted 261s that they'd be willing to send to Chad? I'd be willing to pay shipping both ways.

I think it would be some very valuable info to see Brad's or Randy's MS461 compared to the base saw.

 

[SierraWoodsman]

Thanks Chad, Very interesting.
From the above graphs would it be fair to presume that "In general" the powerband
for larger displacement saws falls off more dramatically than their smaller displacement counterparts in the higher RPM range?
or is the major contributing factor to flatter powerband of the 361 the fact that it's ported?

 

[woodchipper95]

I would like to see a graph of comparable stihl vs. Husky saws. 562xp vs. 362c-m. Then what would we argue about! Nice graphs Chad thanks!

 

[LowVolt]

I would like to see a graph of comparable stihl vs. Husky saws. 562xp vs. 362c-m. Then what would we argue about! Nice graphs Chad thanks!

Flippy caps... Lol

 

[chadihman]

I would like to see a graph of comparable stihl vs. Husky saws. 562xp vs. 362c-m. Then what would we argue about! Nice graphs Chad thanks!

Heck the screws would probably fall out of the husky's. The dyno and me are pretty rough on saws.

 

[Haywire Haywood]

I like that smooth rise in power that the 361 chart shows. Not jumpy or erratic like the other two except for the hiccup between 11K and 11.5K