Official YouTube Video Thread

Crazy on a bike like that you wouldn’t cnc port them. In this day and age on any multi cylinder bike no idea why you wouldn’t cnc port any head but that’s just me.

 

Ok Soyboy

 

I couldn't tell, but it didn't look like they had a CNC machine in that seemingly small shop.

 

What would the cost difference be door-to-door to CNC a porting job vs doing it by hand?

 

Not the cost it’s the consistency, on a bike that costs that much I’d spend the extra $. That being said those ports may be easy to shape consistently by hand.

 

Wouldn't that require the CAD files (or whatever) on the heads be available?

 

Develop port. Cast silicon. Scan/model whatever. Program... Time... Lots and lots and lots of bullshit out there. Just because it's a CNC port doesn't make it a good port.

 

For those in the know, I thought you were supposed to cut or grind the seats after porting or for a valve job. I always thought lapping was what you did on a lawn mower?

 

I don't do port work but it might depend on the desired result. In the case of the video, he wanted to open the port throat as wide as he could but he needed a reference line. He ground the valve face to clean it up, then lapped it in the seat for his reference line. That gives a pretty tight radius on the valve seat, as opposed to a 3-angle or 5-angle valve job, but not every engine likes the same thing and generally accepted practices may not apply to those "odd" engines. Remember that a Ducati has extremely aggressive opening/closing ramps on their cam lobes...port flow at low lift may not even be a consideration when weighed against a higher benefit.

For a SS build with WERA, you can't touch that throat but you can grind/cut the seat ring to match the throat. This may or may not require a valve job afterward. (I would cheat, rob and steal to get every oz. of gain out of that allowance. )

In either case, I can't see going into an engine and not giving it a multi-angle valve job as a generally accepted practice, let alone going into an engine for repair/maintenance and not doing something to speed it up or otherwise enhance a system's efficiency.

As it has to do with port work, the OEMs spend millions on engine R&D. Some of the best results for aftermarket port work come from simply cleaning up the machining/casting imperfections from the factory. Certainly, you can play with clay on a flow bench to reshape the port throats to your liking with respect to varying valve lifts, etc., but simply cleaning up and matching the manifold/throat/seat interface would make a very noticeable improvement on any well-tuned SS machine - and then it's a SB, so might as well get cams, pistons, crankwork...

 

Bunch of nervous guys in Toronto tonight lol.

 

For Fanboy Ritchie.

 

I thought your people didn't care for swimming?

 

Quadriplegics?...

One would think not.

 

I saw Danny Carey on tour with pigface. Just happened across this video. Damn.

 

Don't remember seeing this here, sorry if repost. Must watch on the tube.