Mastermind
Work Saw Specialist
Don't feel bad Glenn........I was born confused. And it's slowly and steadily gotten worse.
Don't feel bad Glenn........I was born confused. And it's slowly and steadily gotten worse.
The 7900 is on the right.I think I must be confused. I thought the 7900 was on the left. Looks to me like the left one has a bigger exhaust port. I didn't look closely at the muffler before. Now I don't see how that would mount to the cylinder on the right (7910?). I take it the 7910 muffler does not have that protrusion that inserts into the exhaust port?
Dazed and confused,
Glenn
You do lose most of the support bracket to port match. Making a gasket is the only way to keep one.7910 exhaust port is about an 3/16 taller and 1/16 wider than a 7900. 7910 port doesnt match up to a 7900 muffler perfect but it can easily be port matched if you want. looks like all the extra that would need ground out of the muffler is just sheet metal and not the thicker bracing inside. even if you dont grind the muffler to port match it i dont think it would hurt much if at all on a stock saw. the entrance to the muffler has a nice rounded edge. i traced the gasket onto the muffler to show just how much of a difference there really was. 7910 gasket on the left and 7900 on the right. sorry for the blurry pics. cheap camera and shaky hands
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If I understand Short Hunter correctly you need raise the cylinder to set the squish with a 460 piston. This means the compression height on the 460 piston is taller than the stock 7900 slug. If this is the case it would be a perfect candidate for a pop up to adjust the squish, and get a little more compression to boot.
I just happen to have a 7900 with a scored piston. I'll have to look into it to see what may work.
The 7900 is on the right.
The stated price is not from a Dolmar dealer.only if you like a red top cover otherwise i would just wait till you need it but $187 USD is a pretty good price for us over here. They list for $221. how that compares to you idk
My guess is that ALL the power loss of he PS-7910 compared to the PS-7900 is due to that awful CAT muffler as most of the other engine parts apparently stayed the same.How much of the reduced stated HP on the 7910 compared to 7900 comes from the wacky muffler?
Those are nicely priced!I have both Homie.
http://sawsalvage.com/collections/all-pistons-cylinders/dolmar-makita-7900-7901
Black ones are BB, plain metal are standard.
That 7300 is no slouch!!! I have a 7900, 7900 84cc BB from watsoner on a 7300, and they are all pretty close. The 7300 is very good on gas and very zippy, the 7900 is strong and zippy, the BB is more low end torque with out the zip, kinda like an 051. The BB and the 7900 suck the gas+++
That BB Kit is still the best aftermarket kit... not one failure, direct bolt on and a reasonable price!!
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