Another chainsaw dyno...

[RI Chevy]

I can definitely corroborate this statement with 7900/10s of both flavors.



Jeff I think you've kind of failed to see the forest for the trees a bit here. As entertaining as it is for us non-porters to see the dyno numbers, that really isn't the point of it. It's a porters tool to help them "see" what each incremental change they make does to the "power" of the saw. I think it's going to be especially great for quickly finding the right "recipe" for new models of saws just like the Echo 7310...

It's also fun as an end user to send in a saw and have Joe run it on the dyno so we can also "see" what we are feeling when we run a given saw. However, it's just as pointless to use this tool to brag about how much power saw A has over saw B etcetera, as it would be to hook up a built diesel to a dyno just to brag about hp/tq at the rear wheels.

Yes sir.

 

[Bigmac]

Torque vs HP.


Torque has to be present at a given rpm as well for intended engine use. Having more torque at 14000 rpm than 10000 rpm will not allow the end user to utilize the power efficiently because a saw loaded down with a chain in wood will be cutting closer to that 10000 rpm mark.
.

Al I respectfully disagree with this, if a saw had more torque at 14k compared to 10k the saw will want to live at 14k+ If a 60cc saw had 3lbs of torque throu the curve but started gaining torque after 10k to a peak of 3.5 at 14k that saw would have 3hp at 5250 6 hp at 10.5k and 3.5 lbs at 14k I believe it would be 9.1hp The saw would have a lot more hp at 14k than 10k the saw would not like to be loaded down to 10k it would feel like it fell out of its power band, and depending on the shape of the curve it like like more rpm, like 14.5-15 and loaded down to 14k. Most motors like to run past there torque peak, and depending were there torque peak is at torque peak as well.

 

[wcorey]

Generally speaking the 'most usable power range' on the graph will sit between peak torque and peak hp,
between those two points is where you really want the widest possible spread in rpm.

 

[Red97]

Version 2.0 worked a bit better.

 

[MustangMike]

That is a very impressive gain!

 

[Bigmac]

Version 2.0 worked a bit better.
View attachment 287585

That’s a nice gain over v1, about a half a lb of torque, moved peak hp up almost 1500 rpm. If you don’t mine me asking, did you add comp?

 

[NightRogue]

That’s a nice gain over v1, about a half a lb of torque, moved peak hp up almost 1500 rpm. If you don’t mine me asking, did you add comp?

I'd guess tighter squish made more difference

Sent from my INE-LX2r using Tapatalk

 

[Red97]

That’s a nice gain over v1, about a half a lb of torque, moved peak hp up almost 1500 rpm. If you don’t mine me asking, did you add comp?

I'd guess tighter squish made more difference

Sent from my INE-LX2r using Tapatalk

Squish is about .030 on both. Just spent more time grinding/opening things on the second round.

 

[MustangMike]

Flow makes Go!!!

 

[Bigmac]

Squish is about .030 on both. Just spent more time grinding/opening things on the second round.

Nice! So some machine work and grinding! Thanks

 

[NightRogue]

Squish is about .030 on both. Just spent more time grinding/opening things on the second round.

I think with tighter squish you can reach 10hp mark, nevertheless fantastic gain. Good job bud!

Sent from my INE-LX2r using Tapatalk

 

[drf256]

Al I respectfully disagree with this, if a saw had more torque at 14k compared to 10k the saw will want to live at 14k+ If a 60cc saw had 3lbs of torque throu the curve but started gaining torque after 10k to a peak of 3.5 at 14k that saw would have 3hp at 5250 6 hp at 10.5k and 3.5 lbs at 14k I believe it would be 9.1hp The saw would have a lot more hp at 14k than 10k the saw would not like to be loaded down to 10k it would feel like it fell out of its power band, and depending on the shape of the curve it like like more rpm, like 14.5-15 and loaded down to 14k. Most motors like to run past there torque peak, and depending were there torque peak is at torque peak as well.

Thank you for the respect. Healthy discussions are what interests me. I think we are actually saying the same thing.

It’s what @wcorey is saying as well. It’s the entire curve, it’s magnitude as well as it’s duration and area.

Case in point would be a 16” bar on a saw cutting a 6x6 cant. As long as a saw has enough power/Tq to pull past the minimum load the chain friction creates on that given bar, it should perform similarly to a bigger saw. It’s why you’ll see a smaller saw keep up with a much larger saw in smaller wood, it can still keep the chain speed high enough for that load.

When you hear someone bragging that their 026 beat an 066 through a cant, you know that doubling the bar/can’t size would put their bragging to rest.

Tq vs. Hp has always been hard to explain. I built my own 406ci SBC for torque as it was built for the street. In a 3000 lb ‘69 Vette with 3.36 gearing and a Muncie M20, it did its job. Once I added a 4.10 rear, I wanted more on top. Now my issue is weather to build the 427/390 I have on an engine cradle or just add AFR heads with a street roller cam to the 406. Or just buy a ZL1 crate motor and call it a day.

 

[Red97]

Thank you for the respect. Healthy discussions are what interests me. I think we are actually saying the same thing.

It’s what @wcorey is saying as well. It’s the entire curve, it’s magnitude as well as it’s duration and area.

Case in point would be a 16” bar on a saw cutting a 6x6 cant. As long as a saw has enough power/Tq to pull past the minimum load the chain friction creates on that given bar, it should perform similarly to a bigger saw. It’s why you’ll see a smaller saw keep up with a much larger saw in smaller wood, it can still keep the chain speed high enough for that load.

When you hear someone bragging that their 026 beat an 066 through a cant, you know that doubling the bar/can’t size would put their bragging to rest.

Tq vs. Hp has always been hard to explain. I built my own 406ci SBC for torque as it was built for the street. In a 3000 lb ‘69 Vette with 3.36 gearing and a Muncie M20, it did its job. Once I added a 4.10 rear, I wanted more on top. Now my issue is weather to build the 427/390 I have on an engine cradle or just add AFR heads with a street roller cam to the 406. Or just buy a ZL1 crate motor and call it a day.

LSA-ZL1 supercharged crate engine

 

[Red97]

Nice! So some machine work and grinding! Thanks

Both saws had the same machine work done, and the same .030 squish.

 

[Bigmac]

Both saws had the same machine work done, and the same .030 squish.

Sorry for the misunderstanding, I thought it was the same saw, version 2. Two different saws makes more sense

 

[Bigmac]

Thank you for the respect. Healthy discussions are what interests me. I think we are actually saying the same thing.

It’s what @wcorey is saying as well. It’s the entire curve, it’s magnitude as well as it’s duration and area.

Case in point would be a 16” bar on a saw cutting a 6x6 cant. As long as a saw has enough power/Tq to pull past the minimum load the chain friction creates on that given bar, it should perform similarly to a bigger saw. It’s why you’ll see a smaller saw keep up with a much larger saw in smaller wood, it can still keep the chain speed high enough for that load.

When you hear someone bragging that their 026 beat an 066 through a cant, you know that doubling the bar/can’t size would put their bragging to rest.

Tq vs. Hp has always been hard to explain. I built my own 406ci SBC for torque as it was built for the street. In a 3000 lb ‘69 Vette with 3.36 gearing and a Muncie M20, it did its job. Once I added a 4.10 rear, I wanted more on top. Now my issue is weather to build the 427/390 I have on an engine cradle or just add AFR heads with a street roller cam to the 406. Or just buy a ZL1 crate motor and call it a day.

I understand what your saying. The vast majority of saw loose torque at rpm, most are losing from the 5k Mark when joe starts the graph. Some builder gain torque everywhere and some flatten the torque curve out farther, the rarest saws stay flat out into the cutting rpm, the dyno is saying that the torque curve could be shifted higher and gains could be made. Saws aren’t like cars an other Motorsports, were you need acceleration, not that it isn’t desirable as a feel. But it theory, a saw dose not need much torque below its lowest cutting rpm, if a saw could peak just below its lowest cutting rpm and maintain torque to max loaded cutting rpm. That’s not an easy build to achieve.

On your vette, I am a small block guy myself, in my 68 camaro, I chose to soften the torque curve off the bottom, I feel you can’t hook up too much torque, I destroked a 400sb to a 377, did 11-1 comp solid roller cam afr210 cnc heads, I ran several different cam’s through the simulators and went with the biggest cam that didn’t loose peak torque. I had a difficult time hooking up the previous sbc, and felt rpm was the answer, and knew more power would be even harder to handle. I have 4.11 gears and a t56 magnum. Car has plenty of torque down low, and revs well to 7500rpm, peak power is almost 7k feels like it has wide power curve rolls on nice even at 2500rpm and at 3500+ rpm it’s explosive. Had to upgrade to autocross tires to make it hook at all, otherwise it would spin the tire at speed, at 55mph it would spin the tire at 3500rpm in 3rd. You can’t beat the big three, heads, cam and compression.
My personal vote is heads cam on the 406, it bbc is heavy, and makes the front end feel funny, imho. The supercharged ls is a tight fit, and expensive!!lol probably 20k plus before your done, and the Muncie will feel outdated. I started out with a 4 speed as well and I had problems with the clutch linkage binding under load, engine was twisting everything up, putting a ratchet strap on the engine helped, but I decided to convert to hydraulic. Long post,sorry

 

[Moparmyway]

 

[Bigmac]

View attachment 287725

Yes they are a lifesaver! Clutch modulation is so much better as well!

 

[drf256]

I understand what your saying. The vast majority of saw loose torque at rpm, most are losing from the 5k Mark when joe starts the graph. Some builder gain torque everywhere and some flatten the torque curve out farther, the rarest saws stay flat out into the cutting rpm, the dyno is saying that the torque curve could be shifted higher and gains could be made. Saws aren’t like cars an other Motorsports, were you need acceleration, not that it isn’t desirable as a feel. But it theory, a saw dose not need much torque below its lowest cutting rpm, if a saw could peak just below its lowest cutting rpm and maintain torque to max loaded cutting rpm. That’s not an easy build to achieve.

On your vette, I am a small block guy myself, in my 68 camaro, I chose to soften the torque curve off the bottom, I feel you can’t hook up too much torque, I destroked a 400sb to a 377, did 11-1 comp solid roller cam afr210 cnc heads, I ran several different cam’s through the simulators and went with the biggest cam that didn’t loose peak torque. I had a difficult time hooking up the previous sbc, and felt rpm was the answer, and knew more power would be even harder to handle. I have 4.11 gears and a t56 magnum. Car has plenty of torque down low, and revs well to 7500rpm, peak power is almost 7k feels like it has wide power curve rolls on nice even at 2500rpm and at 3500+ rpm it’s explosive. Had to upgrade to autocross tires to make it hook at all, otherwise it would spin the tire at speed, at 55mph it would spin the tire at 3500rpm in 3rd. You can’t beat the big three, heads, cam and compression.
My personal vote is heads cam on the 406, it bbc is heavy, and makes the front end feel funny, imho. The supercharged ls is a tight fit, and expensive!!lol probably 20k plus before your done, and the Muncie will feel outdated. I started out with a 4 speed as well and I had problems with the clutch linkage binding under load, engine was twisting everything up, putting a ratchet strap on the engine helped, but I decided to convert to hydraulic. Long post,sorry

Ive got a TKO 5 speed in her now.

 

[MustangMike]

Gawd, for a minute there ... 427 ... 390 ... 406 ... I thought you were putting an FE Ford engine in her!

They were my Favorites back in the day ... and I could build them blindfolded!

The 427 Ford motor was likely the most successful racing motor ever (in it's day), competing very well at NASCAR, the 1/4 mile (M/T's Funny Car broke the 200 MPH barrier with one) and winning the 24 hours of Lemans in 1966 (finishing 1, 2 and 3 against Ferrari, etc.).