Topic: Has anyone wet-flowed their cylinder head?

[Pinhead]

Just as the title states, has anyone performed any wet flow testing on one of our SOHC4's? I've been frequenting GoFastNews a lot lately and it seems to me that a LOT of power and efficiency can be had through wet-flow analysis. Has anyone taken the time (or spent the money) to look at wet-flow?

[ksmith0034]

Are you talking about flow porting?  From what I've learned, flow porting is very good, but still pricey.  It all depends on your budget and need out of your bike.  Most will tell you that the price-benefit ratio is tilted too far toward the price side.  Again, it depends on your budget and ultimate goal.  If you have the cash and want that extra 2% out of your bike, then go for it.  Personally, I have a family and I'm not a racer so it's not cost effective for me. 
My $.02

[MRieck]

 I've never done it but I've heard of people using it to study wall finishes. Is that what you're getting at?

[Pinhead]

Wet flow testing determines if there is any liquid fuel sticking to the port walls, with the ultimate goal of eliminating liquid in the chamber. With a perfectly homogenized charge due to a good port design that looks past raw flow numbers, a LOT of horsepower potential can be realized. A head with good wet flow characteristics may not flow as much on the flow bench, but still beat a more conventional design in an engine where it matters. Also, good wet flow generally relates to lower BSFC numbers, thus getting better mileage with the extra horsepower.

[USN20]

I've read about it, looks like the technology is somewhere in between an art and a science.

Wet flow testing article: http://www.automotiverebuilder.com/ar/eb110670.htm

[MRieck]

Wet flow testing determines if there is any liquid fuel sticking to the port walls, with the ultimate goal of eliminating liquid in the chamber. With a perfectly homogenized charge due to a good port design that looks past raw flow numbers, a LOT of horsepower potential can be realized. A head with good wet flow characteristics may not flow as much on the flow bench, but still beat a more conventional design in an engine where it matters. Also, good wet flow generally relates to lower BSFC numbers, thus getting better mileage with the extra horsepower.

Right. That's why I asked if you getting at wall finishes. Sure...good port design is essential but I know you have focused on wall finish in the past. I've engaged in this debate on other forums too with some guys that are using a lot of testing and CNC motorcycle ports. Essential differences are application...high RPM/high velocity downdraft FI stuff or side draft, low RPM/lower velocity stuff. The downdraft stuff applies to F1 cars too. Their walls are very smaooth as are the new ZX series from Kawasaki. This is always an area of big debate when it comes to the intake port BUT it is very depenedent on application. Everbody is pretty much in agreement with the exhaust port finish and chamber finish no matter what the application. As I've said many times.....people do not like to see a super rough intake port and there is little SAE information to prove a wall finished in 80 grit flap and green ScotchBrite is better or worse then one finished in 50 grit cartridge rolls.

[Pinhead]

While that is one of the things that could be brought up, I was wondering more about port shape as it effects wet flow.