LaserRed01GT
Banned
This is weird because Matt and I are just taking turns using my laptop here at the shop. But the wet flow testing is very interesting. We made a homemade rig here a while back. Watching the green dye being drawn into the acrylic cylinder and seeing how it behaves around the combustion chamber and exhaust valve is very interesting, but we soon discovered that is was also very messy. Very messy! I looked like the Hulk for days.
Joe Mondello is supposed to have a complete set of patented parts to convert an existing dry flow bench to wet. He also is supposed to have his own WFB-2000 wet-flow bench that is very reliable and has a recovery system that eliminates the mess. That stuff just ain't cheap.
I think on the flow/velocity ratios, you will get some varying opinions from shop to shop. But I would honestly have to say that most of the pro's would agree that the flow ratios are more important. typically a street/strip head will perform the best with a 80-85% flow ratio. Some all out Pro Stock or Pro Mod heads can have as low as a 65% flow ratio and still make the most power.
Another thing that is a big player in cylinder head performance is the primary seat angle, venturi undercut angle, venturi radii, and backcut angle. Most of the street/strip heads to this day still use a 45° primary seat angle, but some of the more serious heads out there are starting to use a much steeper primary seat angle. There are also a number of production heads out there now using 50º, 52º, and up to a 55º primary seat.
There is a guy here in Tampa (he has asked not to be named) that has experimented with a 4.6 2v head using 55° primary seat angles. A 2000 Mustang GT with his heads made 356 to the tire on a MD-250 Mustang dyno. This was a N/A car with no nitrous and standard tension rings with a stock oil pan. I cringe when I hear these kids proclaim that 320-330 RWHP is the absolute max out of a N/A 4.6 2V. They just don't understand the technology that is out there nowadays.
Joe Mondello is supposed to have a complete set of patented parts to convert an existing dry flow bench to wet. He also is supposed to have his own WFB-2000 wet-flow bench that is very reliable and has a recovery system that eliminates the mess. That stuff just ain't cheap.
I think on the flow/velocity ratios, you will get some varying opinions from shop to shop. But I would honestly have to say that most of the pro's would agree that the flow ratios are more important. typically a street/strip head will perform the best with a 80-85% flow ratio. Some all out Pro Stock or Pro Mod heads can have as low as a 65% flow ratio and still make the most power.
Another thing that is a big player in cylinder head performance is the primary seat angle, venturi undercut angle, venturi radii, and backcut angle. Most of the street/strip heads to this day still use a 45° primary seat angle, but some of the more serious heads out there are starting to use a much steeper primary seat angle. There are also a number of production heads out there now using 50º, 52º, and up to a 55º primary seat.
There is a guy here in Tampa (he has asked not to be named) that has experimented with a 4.6 2v head using 55° primary seat angles. A 2000 Mustang GT with his heads made 356 to the tire on a MD-250 Mustang dyno. This was a N/A car with no nitrous and standard tension rings with a stock oil pan. I cringe when I hear these kids proclaim that 320-330 RWHP is the absolute max out of a N/A 4.6 2V. They just don't understand the technology that is out there nowadays.