Specialist in outdoor power equipment and outdoor activities such as gardening, fishing, hiking, exploring, etc. if you have questions about saw porting or otherwise email me at [email protected]
Excellent video! The area of the exhaust has a huge effect on true blowdown 👍
@Super-Dave-Outdoors11 сағат бұрын
Exactly! Calculating speed of a pressure drop is way more complex than the degrees between exhaust and transfers!
@jonbobskunkworks20 сағат бұрын
Sweet video!
@Super-Dave-Outdoors19 сағат бұрын
Thanks Jon Bob!
@Doc-Cole_Trickle-of-Chainsaws9 сағат бұрын
👊
@chainsawcanuck21 сағат бұрын
👍👍
@Super-Dave-Outdoors21 сағат бұрын
Thanks!!
@novicelumberjack22 сағат бұрын
That was excellent, Dave! Great job!
@Super-Dave-Outdoors22 сағат бұрын
Thanks! I stumbled through it but i think it should help some people!
@novicelumberjack11 сағат бұрын
@Super-Dave-Outdoors Nah. Those who don't know won't watch and those who already know...well they already know. It's pointless. Just have fun and enjoy making videos. No one seems to listen to anything of substance. Seems like everyone must learn in their own way. And blowdown is a very simple concept that rolls off the tongue and is absolutely nice and easy... so it works for a lot of people to focus on. The idea of a pressure differential is a bit more complex, folks don't seem to get it. So they go right back to talking about blowdown. I've built saws that ran great, but then went back in and just widened the exhaust... boom! It went from great to exceptional. Why? The exhaust pressure dropped faster and allowed the transfers more time to flow the fresh mix. But blowdown wasn't changed in the slightest.
@Super-Dave-Outdoors11 сағат бұрын
It is a legitimate concept but it has been perpetuated incorrectly by so many that any beginner gets sucked into the myth. I'd rather help direct a fresh mind than attempt to change a rotten one.
@Doc-Cole_Trickle-of-Chainsaws9 сағат бұрын
@@Super-Dave-Outdoorssomewhat of a fresh mind being directed here 👍🆙SD👊
@Super-Dave-Outdoors4 сағат бұрын
Eagerness and logical thinking go a long way!
@crazyfeller5704Күн бұрын
👍👍 good stuff! I also look at the muffler outlet size. Also, some mufflers just don’t breathe well and that has to be factored in. I think 20 degrees has become a “ standard “, but intake duration, crankcase size and really just about everything in the cylinder matters. Hell, I’m still guessing 99% of the time!!!
@Super-Dave-OutdoorsКүн бұрын
Yup! Anything that bottlenecks before or after the port can affect it. I think 99% of us are picking numbers arbitrarily and fine tuning with trial and error. Effective, not efficient! If you think about it in reverse blowdown pressure also affects the intake with the standard atmosphere and changing pressures in the crankcase.
@Doc-Cole_Trickle-of-Chainsaws9 сағат бұрын
Morning😊
@jimholz1102Күн бұрын
Good stuff. Now look at two saws of same displacement and port sizes but with different bore and stroke. I hope we don't go crazy before looking at the effect of stratified charge on all the traditional 2 stroke variables.
@Super-Dave-OutdoorsКүн бұрын
Got a long way to go before we get there. But the basic answer is with bore gain you gain possible port width and with stroke you gain mechanical advantage via leverage from stroke. Far more variables involved to say which will make most power but short answer is whichever exerts the most pressure per stroke at a given rpm is going to make more power.
@AndyAlaska375Күн бұрын
Excellent video Dave. 👍
@Super-Dave-OutdoorsКүн бұрын
Thanks!
@Doc-Cole_Trickle-of-ChainsawsКүн бұрын
👍🆙SD
@Doc-Cole_Trickle-of-Chainsaws9 сағат бұрын
💯% helping me!
@aaronpowell48853 сағат бұрын
@@Doc-Cole_Trickle-of-Chainsaws yessir👍🏻
@landendyer97403 күн бұрын
Thanks man! Got the same Z master 2000 and I couldn’t find a single video besides yours.
@Super-Dave-Outdoors2 күн бұрын
No problem, don't make mower belts harder than they need to be!
@lonnieholbert88986 күн бұрын
Ironhorse, Tinman, C Brisco, NL, and yourself
@Super-Dave-Outdoors6 күн бұрын
Sled racers, Moto GP, 2 stroke drag bikes/quads, jet skis/PWC/outboard boats all know what is going on. 99.9% of the chainsaw guys are only scratching the surface, myself included.
@Metalandwoods_longlostdentures5 күн бұрын
@@Super-Dave-Outdoorsis probably the only chainsaw guy to have even read an overmars book.
@Super-Dave-Outdoors5 күн бұрын
Only book i have is the graham bell one but i am going to look for the overmars book now. Soon as i have the extra money i am purchasing the mota 2 stroke simulation software Edit: Oh frits overmars!, i have been trying to find a book by him or Jan Thiel, any recommendations?
@crazyfeller57047 күн бұрын
👍👍 really good info- well thought out and presented. “Questions, or FU…put them in the comments”😂
@Super-Dave-Outdoors7 күн бұрын
Yup, not trying to create problems but if any arise i aint afraid of solving them lol
@crazyfeller57047 күн бұрын
Regular Vanilla Ice
@Doc-Cole_Trickle-of-Chainsaws7 күн бұрын
@@crazyfeller5704 😁
@jonbobskunkworks7 күн бұрын
Get your nerd on!!!!
@Super-Dave-Outdoors7 күн бұрын
Trying to! More complex stuff to come later on hopefully!
@Doc-Cole_Trickle-of-Chainsaws7 күн бұрын
😁 Proudly consider myself part of the SawDorkian tribe!
@902hand77 күн бұрын
Great discussion SDO - made for a deeper morning coffee than usual but got the hamster spinning a lil faster on the wheel 👍👍
@Super-Dave-Outdoors7 күн бұрын
I'm honestly trying to help with this one. No shade thrown at anyone but with the mass amounts of uninformed, misinformed, illogical videos out there on the subject i was doing my best to clarify what i could.
@Doc-Cole_Trickle-of-Chainsaws7 күн бұрын
@@Super-Dave-Outdoors well put IMO, if I understood... then I think whoever is going 2 start traveling down this road will 2 or someone who's already on this road will come away w/ a better understanding of the whole picture. When's Pt2? Teach on!!
@Super-Dave-Outdoors7 күн бұрын
Dont know about pt 2 yet but I may break down a few things to increase my understanding too.
@Doc-Cole_Trickle-of-Chainsaws7 күн бұрын
@@Super-Dave-Outdoors 👊
@Doc-Cole_Trickle-of-Chainsaws7 күн бұрын
👍🆙SD
@IndianaDoug8 күн бұрын
What?🤣 bruh cmon… kzread.info/dash/bejne/hW2Yudl9edWrlrQ.htmlsi=6xW_CwnANnP5MKII Edit: I just tagged you in my 620 vs 4910 video, I don’t think links work on shorts now.
@Super-Dave-Outdoors8 күн бұрын
yup. 4910 had a semi chisel RM and 620 was running full chisel EXL. I bet Brisco's hot 4910s are faster than his 620s now. Just cant build enough compression on a 620 to push the durations like a 4910.
@Mightycaptain10 күн бұрын
Throttle response and grunt should be the aim. Then you get limbing and power to fell and buck. That's what I seem to like best. I don't usually switch saws. The saw that fells is the saw that limbs. That one had grunt. Hard to tell about the throttle response. Seemed a little slow maybe to spool up. That burble at the bottom. Once Rev up it seems to go back easily as long as it isn't from the bottom. Just my observations. Depends on the purpose of the saw. I do a lot of felling( especially lately) so these are the things important to me. Could also be the carb tune.
@Super-Dave-Outdoors9 күн бұрын
Carb tune, once it is running it has decent snap. First 15-30 seconds it straightens out. It would probably have more snap on the throttle if the intake was closer to 77 or 78.
@Doc-Cole_Trickle-of-Chainsaws10 күн бұрын
👍🆙SD
@oakiewoodsman10 күн бұрын
Pretty good work Dave!
@Super-Dave-Outdoors10 күн бұрын
Thanks! I'll provide an explanation of why the 4910 was faster later.
@oakiewoodsman10 күн бұрын
I like it! Thanks for the video Dave!
@Super-Dave-Outdoors10 күн бұрын
Need a new one with the WCS muffler. WCS muffler is much more pleasant to run.
@matthewbutcher20310 күн бұрын
Nice pal, that little saw is getting it pretty good. Happy 4th
Пікірлер
Very well said and laid out! Thank you👍🏻
Thanks! Hope it helps clarify things a little!
👍🆙AP
Excellent video! The area of the exhaust has a huge effect on true blowdown 👍
Exactly! Calculating speed of a pressure drop is way more complex than the degrees between exhaust and transfers!
Sweet video!
Thanks Jon Bob!
👊
👍👍
Thanks!!
That was excellent, Dave! Great job!
Thanks! I stumbled through it but i think it should help some people!
@Super-Dave-Outdoors Nah. Those who don't know won't watch and those who already know...well they already know. It's pointless. Just have fun and enjoy making videos. No one seems to listen to anything of substance. Seems like everyone must learn in their own way. And blowdown is a very simple concept that rolls off the tongue and is absolutely nice and easy... so it works for a lot of people to focus on. The idea of a pressure differential is a bit more complex, folks don't seem to get it. So they go right back to talking about blowdown. I've built saws that ran great, but then went back in and just widened the exhaust... boom! It went from great to exceptional. Why? The exhaust pressure dropped faster and allowed the transfers more time to flow the fresh mix. But blowdown wasn't changed in the slightest.
It is a legitimate concept but it has been perpetuated incorrectly by so many that any beginner gets sucked into the myth. I'd rather help direct a fresh mind than attempt to change a rotten one.
@@Super-Dave-Outdoorssomewhat of a fresh mind being directed here 👍🆙SD👊
Eagerness and logical thinking go a long way!
👍👍 good stuff! I also look at the muffler outlet size. Also, some mufflers just don’t breathe well and that has to be factored in. I think 20 degrees has become a “ standard “, but intake duration, crankcase size and really just about everything in the cylinder matters. Hell, I’m still guessing 99% of the time!!!
Yup! Anything that bottlenecks before or after the port can affect it. I think 99% of us are picking numbers arbitrarily and fine tuning with trial and error. Effective, not efficient! If you think about it in reverse blowdown pressure also affects the intake with the standard atmosphere and changing pressures in the crankcase.
Morning😊
Good stuff. Now look at two saws of same displacement and port sizes but with different bore and stroke. I hope we don't go crazy before looking at the effect of stratified charge on all the traditional 2 stroke variables.
Got a long way to go before we get there. But the basic answer is with bore gain you gain possible port width and with stroke you gain mechanical advantage via leverage from stroke. Far more variables involved to say which will make most power but short answer is whichever exerts the most pressure per stroke at a given rpm is going to make more power.
Excellent video Dave. 👍
Thanks!
👍🆙SD
💯% helping me!
@@Doc-Cole_Trickle-of-Chainsaws yessir👍🏻
Thanks man! Got the same Z master 2000 and I couldn’t find a single video besides yours.
No problem, don't make mower belts harder than they need to be!
Ironhorse, Tinman, C Brisco, NL, and yourself
Sled racers, Moto GP, 2 stroke drag bikes/quads, jet skis/PWC/outboard boats all know what is going on. 99.9% of the chainsaw guys are only scratching the surface, myself included.
@@Super-Dave-Outdoorsis probably the only chainsaw guy to have even read an overmars book.
Only book i have is the graham bell one but i am going to look for the overmars book now. Soon as i have the extra money i am purchasing the mota 2 stroke simulation software Edit: Oh frits overmars!, i have been trying to find a book by him or Jan Thiel, any recommendations?
👍👍 really good info- well thought out and presented. “Questions, or FU…put them in the comments”😂
Yup, not trying to create problems but if any arise i aint afraid of solving them lol
Regular Vanilla Ice
@@crazyfeller5704 😁
Get your nerd on!!!!
Trying to! More complex stuff to come later on hopefully!
😁 Proudly consider myself part of the SawDorkian tribe!
Great discussion SDO - made for a deeper morning coffee than usual but got the hamster spinning a lil faster on the wheel 👍👍
I'm honestly trying to help with this one. No shade thrown at anyone but with the mass amounts of uninformed, misinformed, illogical videos out there on the subject i was doing my best to clarify what i could.
@@Super-Dave-Outdoors well put IMO, if I understood... then I think whoever is going 2 start traveling down this road will 2 or someone who's already on this road will come away w/ a better understanding of the whole picture. When's Pt2? Teach on!!
Dont know about pt 2 yet but I may break down a few things to increase my understanding too.
@@Super-Dave-Outdoors 👊
👍🆙SD
What?🤣 bruh cmon… kzread.info/dash/bejne/hW2Yudl9edWrlrQ.htmlsi=6xW_CwnANnP5MKII Edit: I just tagged you in my 620 vs 4910 video, I don’t think links work on shorts now.
yup. 4910 had a semi chisel RM and 620 was running full chisel EXL. I bet Brisco's hot 4910s are faster than his 620s now. Just cant build enough compression on a 620 to push the durations like a 4910.
Throttle response and grunt should be the aim. Then you get limbing and power to fell and buck. That's what I seem to like best. I don't usually switch saws. The saw that fells is the saw that limbs. That one had grunt. Hard to tell about the throttle response. Seemed a little slow maybe to spool up. That burble at the bottom. Once Rev up it seems to go back easily as long as it isn't from the bottom. Just my observations. Depends on the purpose of the saw. I do a lot of felling( especially lately) so these are the things important to me. Could also be the carb tune.
Carb tune, once it is running it has decent snap. First 15-30 seconds it straightens out. It would probably have more snap on the throttle if the intake was closer to 77 or 78.
👍🆙SD
Pretty good work Dave!
Thanks! I'll provide an explanation of why the 4910 was faster later.
I like it! Thanks for the video Dave!
Need a new one with the WCS muffler. WCS muffler is much more pleasant to run.
Nice pal, that little saw is getting it pretty good. Happy 4th
Happy 4th!