Custom EPO's, mild porting

[jay760]

Any body have any idea how to do the combustion chamber like this

not sure what you would use to get a finish like this.

 

[barncat]

thanks goodgollyjosh. we all like the classic lines of these old motors.

 

[gggGary]

i'd prefer not to post someone else's pics unless specifically instructed to do so. the pics i did post were as far as i took this head, and the next step is eliminating most of the excess exhaust guides and blending them in. may try that on the next motor...

Hopefully jack is still watching and will give the OK.

 

[Jack]

i'd prefer not to post someone else's pics unless specifically instructed to do so. the pics i did post were as far as i took this head, and the next step is eliminating most of the excess exhaust guides and blending them in. may try that on the next motor...

You can post the pictures of your E/P and the instructions on working those areas or I can do the explaining. Once the guide protrusion is eliminated,it really opens up the port,then you can proceed trimming the guide boss,don't knife edge it,you round profile it cuz you want the flow to roll off the guide smoothly without creating resistance.

 

[Jack]

Any body have any idea how to do the combustion chamber like this

not sure what you would use to get a finish like this.

Install the valves to protect the seats and use a course sand grid and sand blast the crap out of it,maybe find a way to install a used head gasket to protect the outer aluminum surfaces. A*rougher texture can be beneficial by inducing a swirling action for the mixture.

 

[barncat]

Jack- just tried a couple times to upload the pic you sent of an exhaust port. can't seem to get it transferred from email to file to edit the size down, also not sure what format it is... have hit the limits of my computer skills...

 

[Jack]

Jack- just tried a couple times to upload the pic you sent of an exhaust port. can't seem to get it transferred from email to file to edit the size down, also not sure what format it is... have hit the limits of my computer skills...

That's the problem I'm having,certain shots I can up load while other's won't

 

[weekendrider]

This is an excellent FREE program that can convert a whole bunch of different extensions.
http://www.irfanview.com/
If by chance you do have a file extension it won't work with.
Open the email/ hit the print screen button/ open Irfanview/ paste, crop and save as a jpg.

 

[weekendrider]

the next step is eliminating most of the excess exhaust guides and blending them in. may try that on the next motor...

Jacks photo

 

[MacMcMacmac]

Any body have any idea how to do the combustion chamber like this

not sure what you would use to get a finish like this.

That chamber looks like it's been skulled.

 

[jay760]

What does skulled mean? I've got two heads both have been ported and both have very similar chambers.

 

[MacMcMacmac]

Skulling is where you remove the entire original combustion chamber and replace it with a precision machined insert built for the compression and flow characteristics you are trying to obtain. High end racebike and turbo bike tech. Looking at the other photos in this thread, it appears now to be stock, but even stock it looks like the chamber is made out of something other than aluminum.

 

[jay760]

All xs's have a steel combustion chamber in the alloy head, but it has been altered from the original, the only all alloy heads are the racing ones that yamaha made