LW: "Ruins People's Motors," and it is a lot, but you'll be amazed at how much low end this engine will have. It'll stay together and make power, and depending on the manifold I make for it, make peak power past 9,000.
HT: In the B16 versus GSR head debate, which will you opt for?
LW: This month, I like the GSR. One of the big things about the GSR head versus the B16 is the quench pad. On a B16, the pads are recessed about 0.038-inch in the head, but the GSR runs flat quench pads, or the head is the quench. I like using quench this way.
In the combustion chamber, the B16 has bulges on each side between the intake and exhaust, and this can be used to influence airflow. The GSR head is not designed this way. The intake port geometry is also different. When you look at them what you first see is the steep angle of the injector on the GSR, and that's because of the 2-stage manifold. The B16 ports are actually lower in the head and lower as they enter the combustion chamber; they're not as steep as the GSR. Airflow studies suggest that the GSR has more of a random turbulence to it, where the B16 is more controlled.
We can make a bit more torque with the B16 head, and I use them on most road racing engines we build. The exhaust is kind of the same way. The GSR exhaust ports have a fairly short bottom side radius, so the exhaust gas has an abrupt direction change as it exits. The B16 has a higher floor to make that radius less, so what we do is weld in the floors on the GSR and then CNC our B16 exhaust port to get the best of both.
HT: It sounds like the B16 is the better head, though you're saying you like the GSR one. Since Honda already had a good head on the B16, why would they create the GSR head?
LW: I think with the greater displacement and the dual runner manifold, another head design had to be made. But if you do the same aggressive valve job on both stock port heads, we can get a bit more high RPM power with the GSR. The port volume and angle lends itself to high revs. But it's inevitable I'll find something new the next time I work on a radical B16 head and it'll become my favorite again. Then in 6 months the reverse could happen. That's how I am on these things; the heads I do are continuously evolving, based on flow bench studies and analysis on our dyno. Each and every head I do is a custom piece, configured for an exact application.
HT: Then we're all set. You'll build a Dart B20 with an 84.5mm bore, drop in a Crower 92mm crank with custom length rods to take advantage of the taller block, and then top it off with a custom GSR head.
LW: Don't forget, we'll be using Endyn's pistons, cams, valvetrain and intake manifold as well.
HT: We'll save that for next time!
 This is one of the keys to...  This is one of the keys to Endyn's success, a custom-built 1000CFM flow bench. The location of many a late night for Widmer, it is here he finds out if his latest ideas will work or not. |  Think Widmer knows a thing...  Think Widmer knows a thing or two about Honda heads? Likely, considering the amount of head castings sitting in his shop. These have all been through a CNC process that is just the start. From here they will get valve work, and then Larry finishes each by hand. |  "Now you listen careful,"...  "Now you listen careful," says Widmer, owner of Energy Dynamics, or Endyn. Being from Texas, he's got big sayings, big opinions, and huge knowledge. Pictured is an F20C head he's working on for a drag car. |