400c Rumors… or just internet trolls.

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Doubtful, I've dynoed hundreds if not thousands of engines at this point. Any human intervention in testing leads to screw ups, hence why we try to remove our influence as much as possibly. Timed cuts is saws is a very vauge way to determine which one is more powerful.
First you have to decide if your goal is to have the dyno tell you that you have higher or lesser horsepower, or if you want to cut wood faster. The reason I suggested that is that more horsepower and more area under the curve doesn’t always cut wood faster. 8hp saws cut faster than 8.5 HP saws and 6HP saws cut faster than 6.5HP saws all the time. All the dyno does is tell you what the torque and converted hp is. If you want to cut faster, you need to cut, time it, and make improvements that make it cut faster
 
First you have to decide if your goal is to have the dyno tell you that you have higher or lesser horsepower, or if you want to cut wood faster. The reason I suggested that is that more horsepower and more area under the curve doesn’t always cut wood faster. 8hp saws cut faster than 8.5 HP saws and 6HP saws cut faster than 6.5HP saws all the time. All the dyno does is tell you what the torque and converted hp is. If you want to cut faster, you need to cut, time it, and make improvements that make it cut faster
Hp doesn't mean much, a dyno will show you the same thing. It's all about useful torque at working rpm. All you're doing is taking the chain varriable out of the equation, and we all know how varriable a chain is. An 8.5 hp can have torque peek and drop off long before a lesser hp engine. We always said torque wins races not hp. Build an engine to have a wide torque curve and it will pull harder longer then a engine built for high hp in a narrow rpm range.
 
First you have to decide if your goal is to have the dyno tell you that you have higher or lesser horsepower, or if you want to cut wood faster. The reason I suggested that is that more horsepower and more area under the curve doesn’t always cut wood faster. 8hp saws cut faster than 8.5 HP saws and 6HP saws cut faster than 6.5HP saws all the time. All the dyno does is tell you what
and converted hp is. If you want to cut faster, you need to cut, time it, and make improvements that make it cut faster
Its all about transferring that engine horse power & torgue potential to the cut in the most efficient manner . Proper sprocket selection & bar & chain combinations applied to a properly timed & tuned engine pays big dividends !
 
Hp doesn't mean much, a dyno will show you the same thing. It's all about useful torque at working rpm. All you're doing is taking the chain varriable out of the equation, and we all know how varriable a chain is. An 8.5 hp can have torque peek and drop off long before a lesser hp engine. We always said torque wins races not hp. Build an engine to have a wide torque curve and it will pull harder longer then a engine built for high hp in a narrow rpm range.
Absolutely correct Sean !
 
So one time you’re cutting 4” branches and 15 minutes later you’re cutting 12” wood, and down at the other end it’s up to 20”. And you’re using the same saw. When you guys are having a kart dynoed, or a snowmobile, or even a car, you rarely need to think about the size of your load changing unless you’ve got your girlfriend riding on the back. So a gain you can see likely translates to something desirable. A chainsaw operates at so many different loads that can neither be a 800hp sbc or a 400hp Cat. If torque wins every time, that means the Cat always wins. if HP always wins, we would build them like the sbc. Try building a saw that’s useful for changing load conditions by only looking at a dyno. Some seem to just want to look at the hp max numbers and lines, some look at torque numbers and lines. Both are failures for building a chainsaw that cuts a variety of wood fast
 
Its all about transferring that engine horse power & torgue potential to the cut in the most efficient manner . Proper sprocket selection & bar & chain combinations applied to a properly timed & tuned engine pays big dividends !
Your car weight never changes. Your kart weight never changes. Your snowmobile weight never changes. The load on a chainsaw changes constantly.
Like racing in the I 500 where one lap you could haul ass empty and the next lap you needed to hook onto a 1000 pound trailer and pull that as well. And repeat empty and loaded every lap until the end. Build that snowmobile from a dyno without a stopwatch it and let me know how it works
 
Your car weight never changes. Your kart weight never changes. Your snowmobile weight never changes. The load on a chainsaw changes constantly.
Like racing in the I 500 where one lap you could haul ass empty and the next lap you needed to hook onto a 1000 pound trailer and pull that as well. And repeat empty and loaded every lap until the end. Build that snowmobile from a dyno without a stopwatch it and let me know how it works
Actually as it pertains to cross country sled racing your load changes alot. Packed snow, powder, deep corners, etc.
When I raced I ran EGT and you could see this on the gauges. Even in circle track riding on ice like the I500 the surface changes as the race goes on. You might be hooked up at the start of the race, but by the end your running loose. Northwest can attest to this.
But I get what your dating in regards to saws.
 
So one time you’re cutting 4” branches and 15 minutes later you’re cutting 12” wood, and down at the other end it’s up to 20”. And you’re using the same saw. When you guys are having a kart dynoed, or a snowmobile, or even a car, you rarely need to think about the size of your load changing unless you’ve got your girlfriend riding on the back. So a gain you can see likely translates to something desirable. A chainsaw operates at so many different loads that can neither be a 800hp sbc or a 400hp Cat. If torque wins every time, that means the Cat always wins. if HP always wins, we would build them like the sbc. Try building a saw that’s useful for changing load conditions by only looking at a dyno. Some seem to just want to look at the hp max numbers and lines, some look at torque numbers and lines. Both are failures for building a chainsaw that cuts a variety of wood fast
No, wete not talking about drag races where you're wot for 1/4 mile. You can vary the load on a dyno, just like real word, the difference is you can take out the other variables. Just the bar and chain add a ton of variables. Real world nice long torque curves at usable rpm produces the best running engines. Period. It's a fact. Chassis dynos let you change the tune of the engine to make up for drive train loses. Real world running let's you fine tune for various situations. Handling, suspension etc. Same as cutting to tune a chain for performance. A saw engine that gets on it torque band and has good hp will be bale to drag a more aggressive chain faster then an engine that doesn't have the same torque range but more total hp. You need to look at it all. I'd you can't tell which engine will give better overall performance from a dyno result then whatever it's attached to is killing the engine.
You port engines so this is what you're ultimately doing with your saws weather you realize it or not. You want an engine that gets it torque at a relative low operating rpm and has enough to sustain it through the working rpm range. Sure cutting cookies let's you see some of that, but it would directly translate to dyno results as well.
 
Actually as it pertains to cross country sled racing your load changes alot. Packed snow, powder, deep corners, etc.
When I raced I ran EGT and you could see this on the gauges. Even in circle track riding on ice like the I500 the surface changes as the race goes on. You might be hooked up at the start of the race, but by the end your running loose. Northwest can attest to this.
But I get what your dating in regards to saws.
Absolutely. The point I was trying to make was that a saw’s load changes by 500? 1000%? If you want to cut 4 x 4, get as much horsepower as you can get. But if you want to be able to dog in on a 20 inch log, the horsepower number matters less
 
No, wete not talking about drag races where you're wot for 1/4 mile. You can vary the load on a dyno, just like real word, the difference is you can take out the other variables. Just the bar and chain add a ton of variables. Real world nice long torque curves at usable rpm produces the best running engines. Period. It's a fact. Chassis dynos let you change the tune of the engine to make up for drive train loses. Real world running let's you fine tune for various situations. Handling, suspension etc. Same as cutting to tune a chain for performance. A saw engine that gets on it torque band and has good hp will be bale to drag a more aggressive chain faster then an engine that doesn't have the same torque range but more total hp. You need to look at it all. I'd you can't tell which engine will give better overall performance from a dyno result then whatever it's attached to is killing the engine.
You port engines so this is what you're ultimately doing with your saws weather you realize it or not. You want an engine that gets it torque at a relative low operating rpm and has enough to sustain it through the working rpm range. Sure cutting cookies let's you see some of that, but it would directly translate to dyno results as well.
i’ve done it for a living for 10 years. In that time I have put 50 saws across Joe’s dyno. And with as many runs as he has done on his own dyno, he admits in video that you can’t replace dyno numbers with cutting evidence.

Would you like me to just tell you that you’re right?
 
i’ve done it for a living for 10 years. In that time I have put 50 saws across Joe’s dyno. And with as many runs as he has done on his own dyno, he admits in video that you can’t replace dyno numbers with cutting evidence.

Would you like me to just tell you that you’re right?
I've dynoed hundreds of engines from single cylinder gas engines up to v16 diesels with plenty of one offs in between. You should readily see the difference in the dyno results to give you a good indication of how the engine will preform real world. Either his dyno results are arw skewed or you're inducing variables you arnt factoring in when cutting. It just that simple.
 
I've dynoed hundreds of engines from single cylinder gas engines up to v16 diesels with plenty of one offs in between. You should readily see the difference in the dyno results to give you a good indication of how the engine will preform real world. Either his dyno results are arw skewed or you're inducing variables you arnt factoring in when cutting. It just that simple.
👌
 
So one time you’re cutting 4” branches and 15 minutes later you’re cutting 12” wood, and down at the other end it’s up to 20”. And you’re using the same saw. When you guys are having a kart dynoed, or a snowmobile, or even a car, you rarely need to think about the size of your load changing unless you’ve got your girlfriend riding on the back. So a gain you can see likely translates to something desirable. A chainsaw operates at so many different loads that can neither be a 800hp sbc or a 400hp Cat. If torque wins every time, that means the Cat always wins. if HP always wins, we would build them like the sbc. Try building a saw that’s useful for changing load conditions by only looking at a dyno. Some seem to just want to look at the hp max numbers and lines, some look at torque numbers and lines. Both are failures for building a chainsaw that cuts a variety of wood fast
I believe I previously stated a balanced saw with usable horsepower & torgue values is what is preferred by most engine builders of any sled cycle or performance saw . Where you achieve peak horse power & the broader the torgue range is where the meat & potatoes of the build exists . As far as load within a sled or cycle it varies vastly when trail riding vs deep powder. with sleds or heavy clay or sand with a cycle Kevin . If you have ever seen the research development of "drive belt" manfacturers in the last 20 years for Performance ATV's or Sleds to meet manufacturers reliability & life cycle requirements , you would not question the torgue requirements or capabilities of today's modern sleds or cycles . Anyhow , dyno testing with properly calibrated equipment & competent or experienced operators can & does achieve Optimium engine performance & valid bench marks for future builds !
 
Your car weight never changes. Your kart weight never changes. Your snowmobile weight never changes. The load on a chainsaw changes constantly.
Like racing in the I 500 where one lap you could haul ass empty and the next lap you needed to hook onto a 1000 pound trailer and pull that as well. And repeat empty and loaded every lap until the end. Build that snowmobile from a dyno without a stopwatch it and let me know how it works
No , actually Kevin engine loading varies throughout the entire race . Snow conditions , ambient temperatures & barometric pressure apply load dynamics within a race to an engine . You start the race on crystilized ice then after a few hundred laps your running on coarse granular snow of a few inches & then within a hundred miles from the finish your running in soup of 4-6 inches of fine ice snow & mud. The frictional gains & additional suspension loading is quite apparent & engine temps & loading escalate accordingly . Ben could give you the same criteria within cycle racing ! P.S. yes timed laps during routine testing on the track or trail is paramount to validate your tuning & engine building perimeters . That's applies equally to saws as you have stated !
 
Absolutely. The point I was trying to make was that a saw’s load changes by 500? 1000%? If you want to cut 4 x 4, get as much horsepower as you can get. But if you want to be able to dog in on a 20 inch log, the horsepower number matters less
sounds about right to me , if there is an inbalance , I would rather have the usable torgue at the working rpm range without a doubt ! I believe Sean has voiced this preference previously !
 
i’ve done it for a living for 10 years. In that time I have put 50 saws across Joe’s dyno. And with as many runs as he has done on his own dyno, he admits in video that you can’t replace dyno numbers with cutting evidence.

Would you like me to just tell you that you’re right?
Don't send him mine for Christ's Sake!
 
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