Building An 064 With A MS 660 BB Kit

[Mastermind]

Here's a different one for you guys...

It's harder to see than I thought it would be, but the jug is bigger than the bore in the crankcase, in other words the piston hits the case before reaching BDC.

That's a big combustion chamber, ain't it???? :msp_ohmy:

I had a case gasket fail recently, so I ain't taking any chances from here on out. That's the good stuff......Johnson Outboard sealer from muh friend Wiggs.

On the case half on the left you can see where I relieved the case for piston clearance.

Anyone know what the propane torch is for????

Yeah I use grease on seals.......Don't everyone????

 

[Bowtie]

Why not just get a good 064 jug and slug and do it right? Kind of a shame to butcher up an 064 like that, and it has been done on here quite a few times. Just my opinion.

 

[pops21]

I'm looking foward to the results. I have most of a 064 I'm itching to put a BB in. Still haven't made up my mind yet.

 

[wigglesworth]

Lookin good my friend. That sealant is the BOMB!!

 

[Jacob J.]

How did your case gasket fail? The case/mixing area generally doesn't see very high pressure, unless of course you're injecting nitrous into the bottom end.

The kart guys were telling me they'd blow sidewalls out of the cases of rotary-valve Euro engines back in the day with bottom end injection. It would have been awesome to see that.

I'm guessing the propane torch is for shooing the cat away if it gets up on your bench.

 

[shelbythedog]

Only those that want to do the job once grease seals during assembly.

Am I the only one who finds it weird that there was no third party reference to Mastermind "meeting the 064/660BB" in the title????

 

[Mastermind]

I'll be adding to this thread as the saw progresses, It's a spare time project, so it may take a few days to build.

The port timing without a base gasket is...

Intake duration: 164° = 82° FTDC
Exhaust duration: 170° = 95° FTDC
Transfers: 120° = 25° Blowdown

 

[Stihl-Pioneer]

I had a case gasket fail recently, so I ain't taking any chances from here on out. That's the good stuff......Johnson Outboard sealer from muh friend Wiggs.

If you ever need more of that gel seal let me know I will send some your way.

 

[blsnelling]

What will you do with that high of an exhaust port, yet the roof is probably flat, or even convex?

 

[parrisw]

Why not just get a good 064 jug and slug and do it right? Kind of a shame to butcher up an 064 like that, and it has been done on here quite a few times. Just my opinion.

Opinions are like A-Holes, everyone has one and only others STINK!:hmm3grin2orange:

 

[parrisw]

Oh, cool build Randy, me likey allot!!

 

[wigglesworth]

Randy, don't forget to upgrade from the 5mm cylinder bolts to
6mm.

 

[Bowtie]

Opinions are like A-Holes, everyone has one and only others STINK!:hmm3grin2orange:

That is correct. And you just stated yours.

 

[Mastermind]

Why not just get a good 064 jug and slug and do it right? Kind of a shame to butcher up an 064 like that, and it has been done on here quite a few times. Just my opinion.

I've got a fine 064 jug and slug, a 066 jug, and...well, I have this BB kit. The numbers on this top end tell me that this saw will be a challenge to build with a #### load of torque. I like a challenge. If everything goes as planned the piston will end up going through the bottom of the case...... Just kidding about the piston.

This saw will end up with a welded popup too, is that wrong????

How did your case gasket fail? The case/mixing area generally doesn't see very high pressure, unless of course you're injecting nitrous into the bottom end.

The kart guys were telling me they'd blow sidewalls out of the cases of rotary-valve Euro engines back in the day with bottom end injection. It would have been awesome to see that.

I'm guessing the propane torch is for shooing the cat away if it gets up on your bench.

Seems like it was flooded, and that helped to blow it out.

The torch is for heating the piece of steel I lay the parts on to heat up. Heat is your friend when putting a bottom end together

Only those that want to do the job once grease seals during assembly.

Am I the only one who finds it weird that there was no third party reference to Mastermind "meeting the 064/660BB" in the title????

That "third party" stuff was wearing on me. :hmm3grin2orange:

 

[Mastermind]

What will you do with that high of an exhaust port, yet the roof is probably flat, or even convex?

Wiggs is gonna build me a popup with that fancy welder at his job. Then I can utilize that exhaust timing. Till it blows the hell up. :msp_wink:

 

[Bowtie]

I've got a fine 064 jug and slug, a 066 jug, and...well, I have this BB kit. The numbers on this top end tell me that this saw will be a challenge to build with a #### load of torque. I like a challenge. If everything goes as planned the piston will end up going through the bottom of the case...... Just kidding about the piston.

This saw will end up with a welded popup too, is that wrong????



Not at all, Im just partial to the 064's. Dont take me wrong, its just the case is not as beefy as the 66 and 660 cases, and the possibility of failure increases with increased power in that application. May never happen. Did I mention I love 064's?

 

[parrisw]

That is correct. And you just stated yours.

Its a joke, lighten up.

Wiggs is gonna build me a popup with that fancy welder at his job. Then I can utilize that exhaust timing. Till it blows the hell up. :msp_wink:

Is there any room to drop the cylinder?

 

[blsnelling]

Its a joke, lighten up.



Is there any room to drop the cylinder?

Still won't buy you less exhaust duration though, not unless you cut the squish band, which is unlikely on these.

 

[parrisw]

Still won't buy you less exhaust duration though, not unless you cut the squish band, which is unlikely on these.

Sure it does. If your squish it at .045 you lower it to .020, you just reduced ex.

 

[Mastermind]

Is there any room to drop the cylinder?

Not without gaining intake timing which I think is a bad idea.

Still won't buy you less exhaust duration though, not unless you cut the squish band, which is unlikely on these.

Again, anything that lowers the jug will increase intake timing. That's the reason for a welded piston.