Makita ea7900

[Colonel428]

Hello. I've got the above mentioned 7900 saw. I bought it new about 6 months ago and it is completely stock. I've seen threads on here and other site that show how to split the muffler and remove the slr. I'd love some real world feedback from guys who have done it - what kind of power gains did you see after doing it to your saw? Thanks a bunch, Steve.

 

[Jonny Quest]

Not too hard to do. I did it on my Dol-Kta 6401 / 7900 BB conversion. I carefully split the seam and opened it up. Fairly simple. Just be cautious with the welder settings. Treat it like welding a body panel on a car repair. I believe I used .023, 70S-6 wire. Good to go. The difference wasn't HUGE, but certainly noticeable.

JQ

 

[huskihl]

I pry open the crimp and fold it back when I’m done.
On a stock saw you won’t notice a huge difference in power, but I’d split it just to get the guts out so it runs cooler

 

[chipper1]

Hello. I've got the above mentioned 7900 saw. I bought it new about 6 months ago and it is completely stock. I've seen threads on here and other site that show how to split the muffler and remove the slr. I'd love some real world feedback from guys who have done it - what kind of power gains did you see after doing it to your saw? Thanks a bunch, Steve.

Welcome to AS Colonel.
As was already said, the power increase isn't much, but it will let some heat out.
You could also send it out for porting, you'll see awesome gains there, the 7900/7910 is a beast ported.

 

[Colonel428]

Welcome to AS Colonel.
As was already said, the power increase isn't much, but it will let some heat out.
You could also send it out for porting, you'll see awesome gains there, the 7900/7910 is a beast ported.

Thank you sir. Any estimate on what the going rate is to have my 7900 ported? It's a work/firewood saw for me and durability/longevity is more important than performance.

 

[Squareground3691]

Thank you sir. Any estimate on what the going rate is to have my 7900 ported? It's a work/firewood saw for me and durability/longevity is more important than performance.Get it ported you’ll never go back !!

 

[Jonny Quest]

[ zipping up flameproof suit ]

If you are just looking for a good firewood saw, you really don't need a ported saw. I had my old 385XP ported by a good, reputable saw dude, but the before/after compare wasn't worth the money in my opinion. Yes, the ported saw was a bit faster in the cut. Yes, it was louder. Yes, it pulled a bit stronger. So what? Perhaps the ported saw gained maybe a second or two in bucking a big log. OK...now what? The non-ported saw did everything I asked it to do. The ported saw did it just a little bit faster. I eventually sold the 385XP and bought a new 390XP. When I first bought the 390XP, I thought about having it ported, but then decided against it. The 390 did wake up a bit after it burned enough fuel to "break in" properly.

End of the day -- I just don't see enough "gains" to justify the expense. Saw longevity in ported vs. non-ported will be debated by many with no definitive outcome. I'm at the stage in life where a good stock OEM pro-grade saw is all I need.

JQ

[ Keeps flame-proof suit on ]

 

[huskihl]

[ zipping up flameproof suit ]

If you are just looking for a good firewood saw, you really don't need a ported saw. I had my old 385XP ported by a good, reputable saw dude, but the before/after compare wasn't worth the money in my opinion. Yes, the ported saw was a bit faster in the cut. Yes, it was louder. Yes, it pulled a bit stronger. So what? Perhaps the ported saw gained maybe a second or two in bucking a big log. OK...now what? The non-ported saw did everything I asked it to do. The ported saw did it just a little bit faster. I eventually sold the 385XP and bought a new 390XP. When I first bought the 390XP, I thought about having it ported, but then decided against it. The 390 did wake up a bt after it burned enough fuel to "break in" properly.

End of the day -- I just don't see enough "gains" to justify the expense. Saw longevity in ported vs. non-ported will be debated by many with no definitive outcome. I'm at the stage in life where a good stock OEM pro-grade saw is all I need.

JQ

[ Keeps flame-proof suit on ]

[Not flaming, as many have had poor experiences]
How big of a log? It’s quite possible to get 35-40% faster cut times out of a 7900 or 385 if done properly. A 40 second stock cut would take 24-26 seconds with those gains. Allows you to cut with a 60cc saw rather than 80

 

[Logger nate]

While agree at the end of the day a stock saw can get the job done a ported saw can make a big difference. Some saws gain more than others. I’ve had a stock 7910 and a ported 7900, night and day difference. 7900/7910 is one saw (of many) that I would definitely get ported.

 

[jltrent]

If you screw the muffler up can you get another? Parts will get hard to come by on those.

 

[Sportfury70]

Rates can vary by who does it, but this is one of those things where you get what you pay for.

You can go so far as having the works with jug machined, tight squish, port timing changed, etc for more money.

Or you can just get the intake and exhaust opened up and flywheel timing advance for a nice bump. Think dedicated drag racer vs fun daily driver. (Not in reliability but just fun factor)

Mine is the second option that I did myself with a muffler mod and correct tuning and it’s still a night and day difference from stock. It’s not going to keep up with some of the wizards that make a living on this site for porting saws, but it’ll still kick the snot out of a stock 7900 series saw.

If it’s just a tool for a job; muffler mod it and leave it be. If you want to have fun making logs with a modified machine, get it ported.

If your anywhere near Buffalo I’d be happy to split a 6 pack and show you how to do it.

 

[Jed1124]

[ zipping up flameproof suit ]

If you are just looking for a good firewood saw, you really don't need a ported saw. I had my old 385XP ported by a good, reputable saw dude, but the before/after compare wasn't worth the money in my opinion. Yes, the ported saw was a bit faster in the cut. Yes, it was louder. Yes, it pulled a bit stronger. So what? Perhaps the ported saw gained maybe a second or two in bucking a big log. OK...now what? The non-ported saw did everything I asked it to do. The ported saw did it just a little bit faster. I eventually sold the 385XP and bought a new 390XP. When I first bought the 390XP, I thought about having it ported, but then decided against it. The 390 did wake up a bt after it burned enough fuel to "break in" properly.

End of the day -- I just don't see enough "gains" to justify the expense. Saw longevity in ported vs. non-ported will be debated by many with no definitive outcome. I'm at the stage in life where a good stock OEM pro-grade saw is all I need.

JQ

[ Keeps flame-proof suit on ]

Ported saws are just a fad……
The 7900 is one of the best, ported, or not.

 

[Colonel428]

Rates can vary by who does it, but this is one of those things where you get what you pay for.

You can go so far as having the works with jug machined, tight squish, port timing changed, etc for more money.

Or you can just get the intake and exhaust opened up and flywheel timing advance for a nice bump. Think dedicated drag racer vs fun daily driver. (Not in reliability but just fun factor)

Mine is the second option that I did myself with a muffler mod and correct tuning and it’s still a night and day difference from stock. It’s not going to keep up with some of the wizards that make a living on this site for porting saws, but it’ll still kick the snot out of a stock 7900 series saw.

If it’s just a tool for a job; muffler mod it and leave it be. If you want to have fun making logs with a modified machine, get it ported.

If your anywhere near Buffalo I’d be happy to split a 6 pack and show you how to do it.

Well, I'm in the Charlotte, NC area and will have to take a rain check on that 6 pack . I feel fairly confident that me and a neighbor buddy can do the muffler mod (which means I supply the beer and tell him how to do it).

 

[Colonel428]

I think I'm going to just go with the muffler mod for now. I need to make money with this saw right now, not spend money on it. And I don't really want to be without it for any length of time since I use it every time I go for firewood, which is pretty often. I get splitting the muffler and removing the slr tube, spot welding the flange/spacer back on and then recrimping the two halves back together. Question- is the current exhaust area with the spark arrestor big enough by itself or is there a need to "open up" more of the exterior area on the muffler. I've kinda gathered some guys do this but I have yet to read anything definitive as to how big another opening needs to be, if at all. And if needed how do you do it? How do you know when you are losing too much back pressure? Thank you gentlemen for your advice and help.

 

[Logger nate]

https://m.facebook.com/story/graphq...wMDAwMDQ4MDY4MDQ4MzpWSzo4ODIxNzU3MTkyNzQwMzM=

 

[Logger nate]

 

[chipper1]

https://m.facebook.com/story/graphq...wMDAwMDQ4MDY4MDQ4MzpWSzo4ODIxNzU3MTkyNzQwMzM=

I can't see that stuff on fascistbook .

 

[chipper1]

Miss his videos/seeing his/tree monkeys work.
Last contact I had with him was to buy a 661 cylinder off him from the oil test he did.
He had a lot going on.

 

[Logger nate]

Miss his videos/seeing his/tree monkeys work.
Last contact I had with him was to buy a 661 cylinder off him from the oil test he did.
He had a lot going on.

Yeah really enjoyed their videos, he did a great job.

 

[Logger nate]

I can't see that stuff on fascistbook .

Basically he’s saying chainsaws don’t need “back pressure” and the bigger the better (exhaust outlet) lol.