066 Rebuild, Port Job etc

[Brewz]

Right!

Its time to kick the tire and light the fire!

I have not taken it past about 8000 RPM yet, It has done a total of 60 seconds of idling and short blips in the garage, and tomorrow it will get a 42" bar bolted on to it and sunk up to its nuts in 4' thick hardwood.

I cant go easy on it....... it will expect it all the time

Treat em mean to keep em keen

I have also switched from Caltex 98 to BP Ultimate 98. I know lower octane fuel can make more power but I will be cutting in 33*C heat (about 92*F) so I like to use 98 to keep the heat down, and I just find it works better than the 91 here in Aus.
The caltex fuel left a nasty black goop in my saws no matter what oil I used. It was worse with the premium Stihl oil which cheeses me off considering what it costs.
I am also trialing moving from 40:1 to a 32:1 mix, and giving Penrite MC2ST Fully Synthetic oil a go.

Fingers crossed it survives..... I am sure it will!

 

[Brewz]

What a great morning!

Bolted on the 42" bar and fired the old girl up, letting it idle over for a few minutes to warm up.

Tuned it up and it now starts to 4 stroke at 13400 rpm with the OEM P&C, bigger openings on the muffler mod and running the K&N air filter.

Super torquey across a wide rev range, it ran the 42" bar like it used to run a 30".

The new fuel/oil mix went really well with the saw now making minimal fumes and smell. The Penrite oil also makes no smoke that I could see, even at 32:1.
I am officially a 32:1 convert!

After 4 or 5 tanks of fuel in dry dusty wood, the K&N air filter is good for another 40 tanks before it needs a clean.
The outer ware cover kept the filter clear and clean with no change in tune, like I would usually experience with a HD2 after a few tanks in timber like this







Now I just need to wait for the new rear cover to show up so I can try my idea of getting the cover to fit on the back again with the new filter in place

 

[dall]

brewz maybe should cover the opening on top of carb with some foam also so top of carb doesnt fill up with saw dust . just a idea

 

[Brewz]

That's a good idea, I will!

 

[Brewz]

I pulled the air filter today while cleaning up the saw and it was spotless inside.

Zero fines and the filter still breathes like it is new with zero restriction.

 

[Brewz]

I am still interested to know if there is a preferred carb when building ab 066 for performance.

 

[Deets066]

I am still interested to know if there is a preferred carb when building ab 066 for performance.

WJ 69

 

[Brewz]

Started work on retro fitting a rear cover to the saw to protect the carb and make it look a bit better when the K&N filter is attached.

Started with a dodgy Chinese knockoff cover..... I was not going to cut an OEM cover up!
hacked a hole in the back of the cover until I was happy with the fit.





"But how are you going to hold it on" I hear you ask.

My plan is to fit a piece of aluminum fat bar between the carb and the velocity stack extending up towards the top and then bent and angled back towards the back.
Drill a hole in the top of the top of the cover and relocate the lock nut to the top



To be continued.............

 

[Deets066]

Started work on retro fitting a rear cover to the saw to protect the carb and make it look a bit better when the K&N filter is attached.

Started with a dodgy Chinese knockoff cover..... I was not going to cut an OEM cover up!
hacked a hole in the back of the cover until I was happy with the fit.

View attachment 15509

View attachment 15510

"But how are you going to hold it on" I hear you ask.

My plan is to fit a piece of aluminum fat bar between the carb and the velocity stack extending up towards the topand then bent and angled back towards the back.
Drill a hole in the top of the top of the cover and relocate the lock nut to the tip

View attachment 15511

To be continued.............

Good idea

I'm gunna cut the filter base to fit on mine

 

[Moparmyway]

I love seeing all of the creativity and different air filter options, but wouldnt installing a Max Flow be easier ?

 

[Brewz]

but wouldnt installing a Max Flow be easier ?

Yeah probably, but why walk with the herd when cutting your own path is so much more fun.

This thing breathes so well it has added noticeable power and revs to the saw.
It ate through 4' thick eucalyptus running a 42" bar like it was butter. It let me dig in the spikes and push the bar in without wanting to bog and drop revs.
Then when I fitted my 25" bar running .404 Stihl full chisel chain, it noodled the 4' high 1' thick rounds in half in about 15 seconds with an 8 pin sprocket. The noodles were landing about 30 feet back. That 404 chain really moves with an 8 pin sprocket.
Once again, dog it in and pull and it just cut faster.

God I love this saw!

 

[Brewz]

Ha ha, I cant wait till I get to porting it

After I get this sorted I plan to get about .030 cut from the squish and sand the base/gasket delete to get compression up a bit..... see how it goes then!

 

[Deets066]

I love seeing all of the creativity and different air filter options, but wouldnt installing a Max Flow be easier ?

Yes it would be easier, but you can't run a V stack with a maxflo

 

[Moparmyway]

Yes it would be easier, but you can't run a V stack with a maxflo

Does the velocity stack really make that kind of a difference ?

 

[Brewz]

A velocity stack offers far less restriction and increases air velocity into the motor.
Increased air velocity will create higher air density in the motor, which equates to a larger volume of air.
More air means more fuel.
More air and fuel means more power.

The velocity stack also helps smooth the airflow passing through the carb. Because the carb rely's on "signal" from the air flowing through it, a more even, consistent flow will allow better tuning and function.

The black plastic diffuser that sits inside the stock filters ( not sure if this is used in the Max flow filters as well ) will effectively stop spit back but will create disturbance in the air flow and reduce velocity as the air has to make its way around corners just before it enters the carb.

One disadvantage I noticed with the v stack is that it is a lot noisier.

With the muffler gutted and the v stack fitted, the 066 is really noisy!!!

I always use hearing protection but it's still loud.

I noticed a big jump in power swapping from the HD2 filter to the V stack and K&N filter.
Picked up a fair few hundred rpm as well with 4 stroking moving from high 12000's to about 13400.

Longer more restrictive intakes are good for low end power and open v stacks are good for top end power.

Who here runs their saw at half throttle?

Not me!

WOT all the way

 

[Brewz]

To add to this, to get the true airflow benifits from a V stack, they should be run with no air filter which introcuced air disturbance,

This is probably good on a race car or bike that won't see much dirt and dust but not feasible on a chain saw.

I also found some info on how to calculate intake length to tune it to intake pulses.
I will do some numbers tonight for a laugh but I think it will involve having the air filter sticking out a long way

 

[Brewz]

Made a bracket to hold the cover on this arvo.
Don't laugh at it being all crooked. It was the only bit of suitable material I could find and I have to drill it crooked as it already had a hole in it.
If it works I will make a better one.

A sneak peak at how it will look





The bracket:



Tomorrow nights job is to make an aluminum block that goes over the stud that the top mounted nut can clamp down on to hold the cover on tight.

 

[Deets066]

Lookin good man

 

[Brewz]

Thanks mate..... its getting there.

I hate the cheap plastic cover!
Its not a perfect fit, its a different color, but i will do the job and I cant bring myself to hack an OEM cover. A new OEM one would likely set me back $300

Haha... just had a thought.
I will put a magnum sticker on it and all will be well

 

[Brewz]

Job done.
It's a bit dodgy and I will probably build a better version but it will do the job for now.

Had to do some plastic surgery



Bored out the alloy block and tapped the inside of the block so it screwed down tight. This gives something for the top nut to clamp the cover onto.







And as I said, to make feel better about the crappy imitation cover, it got a magnum decal to distract attention.
It also gives the saw 20% more power