"Wicked Work Saw" 046/ms460 build

[tlandrum]

well guys its time to do a 046/ms460 thread. I have a saw here that was sent in for a wicked make over and it starts out a little something like this.

 

[rdtreewalker]

opcorn:opcorn:opcorn:opcorn:

 

[z71mike]

Subscribe.

 

[sgt7546]

Subscribed


• Sent from my screen to yours.

 

[splitpost]

I'm in ,always enjoy the build threads

 

[tlandrum]

first things first. I didnt check beginning numbers on this saw because ive done so many of them and know where im going to set final numbers that its not a needed step. first thing I do is get it on the lathe and get to cutting. this cylinder has about .035 out of the combustion chamber then I take .045 off the base to get a squish of .025.

 

[tlandrum]

after doing the machine work I reinstall the cylinder and get my port timing mapped out and marked

 

[pioneerguy600]

opcorn:opcorn:

 

[redfin]

Thanks for sharing.

 

[Adirondackstihl]

 

[tlandrum]

now we have the finished port shapes

 

[tlandrum]

final numbers
squish is set to .025
intake timing is 160 total duration
exhaust timing is 162 total duration
18* of blow down
compression comes in at about 180

 

[Venomvpr900]

Very nice work!

 

[Milkman31]

Awsome!!!I wish I could make myself understand this. to many numbers

 

[tlandrum]

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

 

[bootboy]

Blowdown is degrees with top of cylinder above all ports. Effectively a completely sealed combustion chamber. Correct?

 

[tlandrum]

blowdown is referring to the amount of timing between the opening of the exhaust and the opening of the transfers.

 

[big t double]

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

 

[bootboy]

blowdown is referring to the amount of timing between the opening of the exhaust and the opening of the transfers.

Gotcha. So on the down stroke, exhaust opens 18* before the transfers.

 

[tlandrum]

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

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