My point was that cheap power is to add cubic inches. But your wanting stock size to experiment with. Also my other point was that because your dealing with a very Small amount of cubic inches I wouldn't be expecting a whole lot. Unless you put it in a 1500 pound roadster or something light, then you might see that engine wake up a bit more. Keep in mind the 230,250,292 all had the same bore size. More air flow doesn't hurt. The 1.72 intake is rather restrictive, not mentioning that head bolt boss. And I'm not Comparing it to a 292, I'm Saying that adding cubic inches Helps. lol Hence why I mentioned stroking it to a 250.
First.... 230 is not "Small" cubic inches by any means, LOL. That's 3.8 liters, which is HUMONGOUS by European standards. I can easily make 200HP out of a 2 liter 4 cylinder. 100hp per liter of displacement has been achieved decades ago and is now more or less a standard. In contrast.... 3.8 liters should EASILY make 300-380hp.... right?
My 2 liter 1937-based design VW beetle is 2 liters and almost hitting 200hp. USA has always made horsepower primarily with displacement, not focusing on breathing, flow, and efficiency. I wanted to optimize the 230, to see what it could do. Logic says, there's gotta be a lot of reserve power hiding in 3.8 liters of displacement, which is a LOT of displacement. The design is just very, very inefficient. Choked down by many things.
The head is already ported and lumped so it is about as good as it can get with reasonable amount of work. Not sure everyone agrees lump kit is reasonable either. Bigger valves could give me a little more power, but I find it hard to believe that the difference could be as dramatic as some posts here are trying to make you think they do.. I have done many engines with larger valves, and many with stock valves. At THIS mild level of tune, I don't see them being a major bottleneck. It is not the secret key to unlimited power.
