Single boost port?

Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F /

On my Vespa, I need to throw together my extra engine pretty quick to try to make it to an event in ypsi. I’ve only cut one boost port so far on my finger port cylinder, and won’t have time to crack the cases and cut for boost ports. I know the transfers need to be the same, just wondering if having only one boost port off center would cause issues

Re: Single boost port?

Dirty30 Dillon /

Do you have corresponding holes already cut in the piston? If not, then it won't matter much at all.

If you do, it probably won't cause negative problems, but you may find it burns very unevenly.

Re: Single boost port?

its not gonna matter, I was staring at a vespa cylinder and it's all unsymmetrical.

Re: Single boost port?

Dirty30 Dillon /

> pat splat Wrote:

> -------------------------------------------------------

> its not gonna matter, I was staring at a vespa cylinder and it's all

> unsymmetrical.

Stock cylinders (am most of the aftermarket) are pretty symmetrical, just not along the vertical center line.

Re: Single boost port?

Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F /

Ok cool. I’ll tear this engine back down once I get my other engine setup assembled and in this bike and do it right

Re: Single boost port?

Keep close watch on your plug reading and pull the head frequently to check the piston crown wash. Poorly placed or angled transfer ports can cause very bad things at high cylinder pressure, AKA: WFO...

Re: Single boost port?

Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F /

decided to just go grab my gray grande instead of risking this motor

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account