Exhaust spacer
- Thread starter MinnesotaJon
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MinnesotaJon
ArboristSite Member
I am kind of surprised thought there would be some more opinions on this. For 20 bucks I might buy it just to play with. I have spent that much in worse ways.
Kanscruzer
OK
It's your money , spend it anyway you want.
send me the twenty...
and i will give you any story you want.
Yes it works great,better than a turbo,who needs nitious when you have a exhaust spacer,Makes any husky run as good as a Stihl, makes any Stihl run as good as a Husky,Best use of $20 eveha
and i will give you any story you want.
Yes it works great,better than a turbo,who needs nitious when you have a exhaust spacer,Makes any husky run as good as a Stihl, makes any Stihl run as good as a Husky,Best use of $20 eveha
An engine's carb pulls in air, mixes it with fuel, that gets pulled into the cylinder. Then whatever is left after combustion gets released out the exhaust.
If the saw has better airflow on the intake side than the exhaust side, additional pressure is generated while all the exhaust gets squeezed out the smaller exhaust system.
So putting a little spacer on the muffler might get you an extra microsecond of full volume exhaust flow on the first stroke while that tiny additional space fills with 1cc of exhaust. I don't see how that increases the flow rate, though I guess the pressure of the whole system might be lower by a small amount due to more volume before the muffler? I mean, you're adding one or three cc of space outside of a 30-120cc cylinder, in system that probably already had a larger space inside the muffler, so it's not going to be a huge swing.
So in theory maybe a small benefit could exist there. I'd be surprised if you could see a real world benefit.
If you were to spend the $20 on a drillbit and some beer, and then use the drillbit to convince your muffler to have an airflow capacity that at least matches the saw's air intake flow rate, you would see a real performance gain. (Sometimes a large one depending how stopped up the stock saw was, ask any Echo owner.)
If the airflow of the exhaust system is not a bottleneck, adding volume to the space between the cylinder and the muffler is of zero benefit to anyone except the guy who has found a way to charge $20 for a spacer, as far as I can see.
Kanscruzer
OK
Well said , if increased exhaust pull is what you are looking for, use that drill bit & weld on a pipe to gain ex pull
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But wait.... if you buy now, you will receive absolutely free this set of steak knives! 
I dunno... if
I dunno.... beer and a drillbit or steak knives and a spacer.... sorry, the muffler mod is still winning this contest.
Although if you up your offer to beer and steak, you still have a shot at selling me on this deal (you can keep the spacer tho).
But wait.... if you buy now, you will receive absolutely free this set of steak knives!
I dunno.... beer and a drillbit or steak knives and a spacer.... sorry, the muffler mod is still winning this contest.
Although if you up your offer to beer and steak, you still have a shot at selling me on this deal (you can keep the spacer tho).
MinnesotaJon
ArboristSite Member
All my saws have muffler mods I know it works well. But straight flow is not the best, that’s why dirt bikes and race saws have big expansion chambers with small outlets. Back pressure does something good for two strokes. I know that this little spacers gains would be minimal. I just thought it was neat, thought maybe some one had tried something similar but with an inch spacer or two then the muffler for expansion and some back pressure different size holes. I am not new to motors but am new to chainsaws just trying to learn here.
Well, warm it up well, measure idle and WOT RPMs with a tach, slap the spacer in, repeat. Unloaded RPMs aren't torque and all that, but it should give you some idea if there has been any change. Tell us what you see!
If you don't have a small engine tach, you can get an inductive one for about $10 on Amazon- you'll use it in future to tune your carbs, so it's a good purchase.
I don't think you'll see anything more than the variation you'd normally see between two sets of measurements, but maybe I'll be wrong and we'll all be fabbing muffler spacers this time next week. Let us know, props for trying it out.
What affect might it have on suck-back? (for you older members)
What affect might it have on suck-back? (for you older members)
Next craze double muffler gaskets equals 2 barrel exhaust next four barrel than six pack where will it end?
Kash
Kash
Kanscruzer
OK
I'm hoping it ends ,,,,,, NOW
