318 build

Dan the man said

He may have to be told as it's appent to me that he doesn't understand that bigger valve's and ports affect port velocity plain and simple and that the bigger valve's and ports move the powerband up. Am I wrong that those same bigger valve's and ports hurt port velocity which hurts both throttle response and low to midrange torque, is this correct or not.

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Like Newbomb said…

Here’s the deal, all of the engines are basically under valved. The idea of killing port velocity is a possibility if you screw things up badly enough. This would be an out of wack combo. The issue here is the target goal which is an unknown even with the approximate compression ratio and cam so a provided. Much needs to be filled in. Too many blanks.

The 318 can use a 2.02 valve and even more cylinder head port size. I wouldn’t do a lot as a smaller port will have a good velocity and pedal response and looking at what the OE poster wrote, with some assumptions, it’ll be fine.

Unless the car is going to use a 2.45 rear gear, 28”+ tires, a starter converter while expecting a stock driving experience. This combo is off.