Dolmar 64xx/73xx/79xx series, smurfs and solo 665/675/681 thread

[RI Chevy]

Who ported the 372?

 

[Steve]

Who ported the 372?

Ironhorse




Not at all!!!!

Was built by a very reputable builder on this site.

 

[RI Chevy]

Lol...

 

[Steve]

I'm a dolly fan as much as anyone, but that xpw should walk that 7910, especially if the xpw is ported.

I am also running a zama c3 carb on the xpw. Not a big hd12.

 

[sawfun]

In defense of the 372, it will easily oil a 36" bar. Can a 7900 oil a 36" bar well?

 

[TreeLife]

In defense of the 372, it will easily oil a 36" bar. Can a 7900 oil a 36" bar well?

Nah, they pretty much oil a 28" well. Beyond that is pushing it without modding the oil pump, in my experience.

 

[huskihl]

Nah, they pretty much oil a 28" well. Beyond that is pushing it without nodding the oil pump, in my experience.

They’re decent with a new high output control bolt. But that fades quick like

 

[chipper1]

Same bar and chain and wood. The 7910 just feels like it has more balls. Maybe it's in my head? Xpw was built right. Its strong. Just feels like i can lean on the 7910 harder.

What's this feels stuff, gotta be stopwatch faster or it don't count, lest that's what I was told lol.
Pics of the slow xpw please .

 

[Steve]

What's this feels stuff, gotta be stopwatch faster or it don't count, lest that's what I was told lol.
Pics of the slow xpw please .

How about a video Brett?

 

[chipper1]

How about a video Brett?

Me likey.
I think I remember that video.
Have you cut much with them side by side, many times its hard to tell on saws you don't run often. But seeing the MMS 7910 hp on in the dyno thread could sure help convince someone they are great runners.
Smaller wood, stock xpw.

Ported 2171.

Ported 7900.

 

[Steve]

Me likey.
I think I remember that video.
Have you cut much with them side by side, many times its hard to tell on saws you don't run often. But seeing the MMS 7910 hp on in the dyno thread could sure help convince someone they are great runners.
Smaller wood, stock xpw.

Ported 2171.

Ported 7900.

Not side by side. I only take 2 saws with me when i cut wood. My 50cc and an almost 5 cube. I my be able to put them side by side this week. For science and stuff.

 

[huskyboy]

I am also running a zama c3 carb on the xpw. Not a big hd12.

Yeah they hurt the power a little bit on a modified saw. I was running out of fuel with a stock C3m in the wintertime on my ported 7900 (about 2 - 2 1/4 turns out on the H). I drilled the main jet to .55, thinned the shafts and bored out the carb from 16.6mm to 17mm. Which is still smaller than the HD12 in bore/jet size, but the saw ran much better. Much easier to just bolt on a HD12 than fugg around with modding the zama honestly. However for a stock saw the zama is fine though, it’s reliable if you get a good one.

 

[Steve]

Yeah they hurt the power a little bit on a modified saw. I was running out of fuel with a stock C3m in the wintertime on my ported 7900 (about 2 - 2 1/4 turns out on the H). I drilled the main jet to .55, thinned the shafts and bored out the carb from 16.6mm to 17mm. Which is still smaller than the HD12 in bore/jet size, but the saw ran much better. Much easier to just bolt on a HD12 than fugg around with modding the zama honestly. However for a stock saw the zama is fine though, it’s reliable if you get a good one.

I like the fuel circuits in a zama better than how walbro sucks the low side fuel out of the main check circuit. Less finicky on adjustments.

Throttle and choke shafts have been thinned on the xpw too.

 

[chipper1]

Not side by side. I only take 2 saws with me when i cut wood. My 50cc and an almost 5 cube. I my be able to put them side by side this week. For science and stuff.

Look forward to seeing the science, everyone these days is talking about following the science, depends who the scientist is!

 

[huskyboy]

I like the fuel circuits in a zama better than how walbro sucks the low side fuel out of the main check circuit. Less finicky on adjustments.

Throttle and choke shafts have been thinned on the xpw too.

I like the tilly 296 better than either one of them, that’s the one I want to try next on a 7900. I have one, just haven’t been motivated since I got the zama running right. Modified zama works just fine for a worksaw.

 

[Steve]

I like the tilly 296 better than either one of them, that’s the one I want to try next on a 7900. I have one, just haven’t been motivated since I got the zama running right. Modified zama works just fine for a worksaw.

HS296?


Might have to look into that.

 

[huskyboy]

HS296?


Might have to look into that.

Yup the only problem is that it’s not exactly a straight bolt on I believe. Might have to tweak some stuff. Haven’t tried fitting it so I am not certain.

 

[huskihl]

Yup the only problem is that it’s not exactly a straight bolt on I believe. Might have to tweak some stuff. Haven’t tried fitting it so I am not certain.

Hard to get a stock air filter to work without carving them up. The high idle linkage on the left hits the bottom of the filter and the impulse on top of the carb hits the other side of the filter. Plus, there’s not really a good way to hold them in there because the filter elbow no longer has the rubber button hold down on the bottom. Probably not great for a worksaw

 

[huskyboy]

Hard to get a stock air filter to work without carving them up. The high idle linkage on the left hits the bottom of the filter and the impulse on top of the carb hits the other side of the filter. Plus, there’s not really a good way to hold them in there because the filter elbow no longer has the rubber button hold down on the bottom. Probably not great for a worksaw

Thanks for the insight, I will be saving that carburetor for a 385/390 then most likely. The modified c3m and hd12 are good enough for me.

 

[huskihl]

Thanks for the insight, I will be saving that carburetor for a 385/390 then most likely. The modified c3m and hd12 are good enough for me.

They work great on a 372. More room in the carb box