[Stan Weiss]

Originally Posted by dci

Pastry chef, I agree the rpm's will need to be high. That is why I chose the cubic inch I did. It's not to big, but it still big enough to make the 2.3 goal. With a 4.400" bore we can use a big enough intake valve to flow enough air to reach the rpm's we need. I think that on that bore size. An inline valve type head could accommodate a 2.350" - 2.380" valve and still be far enough away from the cylinder to be efficient. That valve is a little bigger than the 52% rule, but I'm not sure that the old 52% rule is still being used any more.Especially since everyone found that shrinking the exhaust valve does not hurt the HP. By shrinking the exhaust valve down it makes more room for the valve package.


Tiger Paw, The time part doesn't scare me. It's the money part LOL. I have not considered that arrangement for my heads, but I am always open to new idea's. I still need to prove to myself though that the way I have my port designed now it will be a limiting factor. I am not so bull headed or blinded though that if someone has a better idea that I will not consider it. I have a port that we have been developing in my 5 heads right now that has about 4.5" csa. at the pushrod or opening. It sounds really smooth on the bench and does not back up. So I am really anxious to get it on an engine to see how the port performs. Unfortunately though it is going to have to wait for now since I was chosen for the engine masters challenge (not enough time and money LOL). We think this port is way to big to operate within the rpm range of the challenge. I know everyone is all cranked up about the pushrod being in the port, but until I have tested and tested and tested for myself. I cannot let it rest.

Bruce, When do you think you will get your software functional again? Do you by any chance have the software to determine intake and header spec's?


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

Don,
I have Larry Meaux PipeMax software which does headers / exhaust systems and also intake lengths. If you need some numbers run.

Stan