"Wicked Work Saw" 046/ms460 build

[bootboy]

I've noticed some builders give timing numbers in degrees of the durations and some give just straight numbers of when the ports open...mind explaining why that is...I'm stupid and don't follow the duration readings very well

That's a good point. I understand total durations, but I'd be curious to know the start and end of those durations relative to 0* or TDC.

 

[tlandrum]

160* total ex is 100*
160* intake duration is 80*

 

[treesmith]

Nice work terry!

 

[bootboy]

160* total ex is 100*
160* intake duration is 80*

And that's top of the piston, correct?

Or it is top of the ring?

 

[tlandrum]

top of piston

 

[komatsuvarna]

That's a good point. I understand total durations, but I'd be curious to know the start and end of those durations relative to 0* or TDC.

Simple math will get ya from one to the other. Everyone has their own way to measure I guess................

If the exhaust opens at 100*. Take 100* x 2 and that equals 200*. There is 360* in a total stroke so subtract 200* from 360* and that leaves 160* total open duration. Same for the transfers. Do the opposite to go from duration to ATDC.

On the intake, double it. If it opens at 80*, the duration is 160*.

 

[big t double]

160* total ex is 100*
160* intake duration is 80*

Welp...now I'm thoroughly confused...I think I will sit quietly in the corner and look at the pictures...thanks for posting the build threads...they're why I joined here

 

[HuskStihl]

I guess a video of a wicked work saw 460 is in order

Mmmmmm....Torquey!

 

[bootboy]

Simple math will get ya from one to the other. Everyone has their own way to measure I guess................

If the exhaust opens at 100*. Take 100* x 2 and that equals 200*. There is 360* in a total stroke so subtract 200* from 360* and that leaves 160* total open duration. Same for the transfers. Do the opposite to go from duration to ATDC.

On the intake, double it. If it opens at 80*, the duration is 160*.

Got it


Subtract total duration from port opening to find port closure


My brain wants to put all of this in terms of trigonometry. So I'm having to translate all of it.

 

[rdtreewalker]

Looks good

 

[Moparmyway]

I have a Wicked Work Saw kit for my 044 ............ runs and sounds just like this video. I have about 10 tanks through it now.
AWESOME job on the kit ............I have an AWESOME 044 now !!!!!!!!!!!!!!
Thanks Terry !!!!!!!!!!!

 

[tlandrum]

your welcome my friend

 

[Naked Arborist]

I have always used duration on my timing since back in the days of building car engines. when I bought a cam I bought in by the duration not by when the valves opened

You need a bigger degree wheel lol.

So, I find someone who understands total duration is more important than lift or opening points. You bought the way I always have, good to know. Now, how many will know we can move the cam around or "degree it in"? Last but not least lobe separation angle. Bet I lost most of them with that statement. This is what makes a 2smoke sooo much easier to tune for timing. After doing cams in cars, this "IS" so much easier to do. Who agrees with that statement?

Good runner there Terry.

Sometime we need to discuss lift under the curve and intake velocity based on ramp rate and angle.

 

[TK]

Did you say you were giving this saw a "makeover" ?????? This place sure has changed in the past few months.....

 

[Mastermind]

These ported saws are just a passing fad.....

 

[Adam Smith]

The bigger the degree wheel the more accurate it is, I have a 20 inch degree wheel that I use on both my saws and V8s, Ya it looks pretty goofy on a saw.

 

[sgt7546]

Generally speaking what is the cost to port a stock MS 460 that's getting a little tired.


• Sent from my screen to yours.

 

[nmurph]

$250 + shipping and any parts that need replacement.

 

[sgt7546]

$250 + shipping and any parts that need replacement.

Thank you Mr. Murph.