670 Jonsered power build. Need input please

[Kozak Logging]

I'm seeing a gain of about 4cc total and .3 hp gain. I think that would be a good build for what I'm looking for. I would guess and hope to see a total of .6 hp total gain with a modded muffler bringing me to a total of 5.5hp maybe a tad more? If I go with this and do the full swap.. can I fit a high velocity air system under the lid?

 

[Kozak Logging]

Guys I think this guy is trolling

Actually I'm not close to trolling. I'm here as any new member and am asking questions.

 

[Adirondackstihl]

Guys I think this guy is trolling

No he's not

 

[Adirondackstihl]

I'm seeing a gain of about 4cc total and .3 hp gain. I think that would be a good build for what I'm looking for. I would guess and hope to see a total of .6 hp total gain with a modded muffler bringing me to a total of 5.5hp maybe a tad more? If I go with this and do the full swap.. can I fit a high velocity air system under the lid?

Horsepower ratings are always a sore subject with chainsaws. They're overrated IMO.

To semi-answer the question, we can only hope that someone who had done this swap will chime in.
Too bad @spike60 isn't here

 

[WKEND LUMBERJAK]

Actually I'm not close to trolling. I'm here as any new member and am asking questions.

Please accept my apology.

 

[Kozak Logging]

Please accept my apology.

Its alright man. I'm a auto and heavy equipment mechanic, not a big saw saw mechanic, besides tuning and maintainence. Just want a decent build, maybe do the swap above i talked about and still have somebody mill it a little and go with that setup.

 

[mdavlee]

Out of the ones I ran the 266 seemed to be the hottest out of the box. I've not ported a 268 but the 266 I have runs so good I won't tear into it.

 

[mdavlee]

Its alright man. I'm a auto and heavy equipment mechanic, not a big saw saw mechanic, besides tuning and maintainence. Just want a decent build, maybe do the swap above i talked about and still have somebody mill it a little and go with that setup.

If you want the degree wheel I'll see if I can find it. I moved it the other day.

 

[WKEND LUMBERJAK]

Now we need a how to on a degree wheel. I know were one is but i hate to go over there except to visit with family

 

[Kozak Logging]

Out of the ones I ran the 266 seemed to be the hottest out of the box. I've not ported a 268 but the 266 I have runs so good I won't tear into it.

I think I'm going to do the kit I spoke about. Mastermind said he's booked til April I believe. I think I will be happy with the build I spoke about.

My only concern is this.: I found a piston and cylinder kit for 35.00 on ebay, its a off brand one. Now I found one built by
Meteor, but those are 135-150. Is that like the best brand name? If anybody has input please enlighten me. I don't need to go cheap, but if its just as good as Meteor I will give it a try. But I do want durability as well. Not just a run it a day and blow up saw lol.

 

[mdavlee]

Stick with OEM or meteor. The new hyway kits look very nice so if Hl has one then maybe try it. It seems they're trying really hard. The oem prices have dropped considerably so check with some dealers before you spend more for aftermarket.

 

[jockeydeuce]

Reading through this thread, I think the OP has two choices. Send the saw out to Mastermind for the full meal deal or stay with his original hopes of getting into it himself and staying with the basics ( with a little guidance from the fine membership here I think he could do squish adjustment and muff mod)....And have the bonus of learning something!

So Kozak, are you saying the 670 has a recent OEM piston? .If so, you may not even need to be shopping for pistons.

 

[beaglebriar]

Now we need a how to on a degree wheel. I know were one is but i hate to go over there except to visit with family

You can just check out Masterminds video on YouTube.

 

[Kozak Logging]

Reading through this thread, I think the OP has two choices. Send the saw out to Mastermind for the full meal deal or stay with his original hopes of getting into it himself and staying with the basics ( with a little guidance from the fine membership here I think he could do squish adjustment and muff mod)....And have the bonus of learning something!

So Kozak, are you saying the 670 has a recent OEM piston? .If so, you may not even need to be shopping for pistons.

Yea, we put a piston OEM replacement in it just to do a basic rebuild many years ago along with crank bearings and seals.. Wouldn't mind replacing the bearings and seals again just to be sure it has a long life and to do it right the first time.

 

[Kozak Logging]

You can just check out Masterminds video on YouTube.

I'm not sure on degreeing.... If I just got the xp kit, I would gain 4cc displacement and I would think alot of power as well. I did swear today I saw the kit it said 52mm big bore kit, where it still had a pulsator in the new cylinder and stated can use stock carb. I have to find it again and I will post a link. Again I think that was a off brand. I will post em up and see what you guys think.

 

[beaglebriar]

In most cases the old saying "There's no replacement for displacement" is true but in chainsaws its more about port timing and flow. The big bore kits can be a real let down because most are poorly built.

 

[Adirondackstihl]

99.9% of all big bore cylinders will typically produce LESS power than the OEM cylinder you replace it for.
Stick with OEM stuff.
Find a good used 272 top end.
I know someone that might be able to help.
@bplust

 

[huskihl]

Horsepower ratings are always a sore subject with chainsaws. They're overrated IMO.

To semi-answer the question, we can only hope that someone who had done this swap will chime in.
Too bad @spike60 isn't here

I've done it. But in my opinion, there's nothing wrong with a 670 jug for what he wants to do. I'd spend my money on porting, not new aluminum. Unless his intake boot is bad..they're scarce. If that's bad, and $ isn't an issue, convert it and the intake to 272 and port it

 

[huskihl]

99.9% of all big bore cylinders will typically produce LESS power than the OEM cylinder you replace it for.
Stick with OEM stuff.
Find a good used 272 top end.
I know someone that might be able to help.
@bplust

And yes. If it's out there, Bryan probably has it

 

[Kozak Logging]

99.9% of all big bore cylinders will typically produce LESS power than the OEM cylinder you replace it for.
Stick with OEM stuff.
Find a good used 272 top end.
I know someone that might be able to help.
@bplust

That would be great if you know someone who has it. I've been tossing around the thoughts on getting a Meteor kit and using my stock carb or doing the full 272 swap with carb too... Do you think carquests machine shop would be able to mill at all? Or is that something a saw specialist would have to do?