I bought the car with the engine in it as an unfinished project. My machinist screwed the combo together under the advice of a well respected Mopar racer in the US.
Basically a 9 to1 360, heads were 302's with a 1.84 valve no real port work just a tidy up around the valve job, Air gap 750 3310...
As an example Dan Smiths 410 stroker 360 with stock ported heads runs 9.6s at 3050 lbs. He does that with just 28 degrees of total timing. The exceptional performance and the fact he does it with only 28 degrees of total timing is the give away. The burn is very fast and efficient. Slow burns...
It takes an understanding of how an engine actually works. Here's a hint: Its not an AIR PUMP. Until you can grasp that detail you'll always need a bigger head to make more power while those that do understand can make more power with a lot less than you need.
It is and the guy knows what he's doing. There are many others doing close to that but with more. You would need to understand his philosophy and approach to engine building to understand how he's able to do it. Its certainly not all about BIG heads to do it.
Smart people do not rely on luck.
https://wright-here.net/files/articles/phr_1109_sbo/phr_1109_sbo_ocr.pdf
Knowing he wouldn't need enormous runners for the amount of cubes, Dale kept the volume down. He says: "The intake port is way smaller than the original. ,think the factory was 152 cc and...
Sometimes even a blind squirrel finds a nut. Go and think about that sentence and figure out where your blind spot is.
I'll leave you with this: Just because a head flows 250 cfm that doesn't mean that is what the engine uses.
You are giving advice that contradicts the title of the thread.
That figures. When you have and have seen results contrary to what people here say and repeat ad nauseum because they don't actually know. Its not hard to get a 318 head over 200 cfm and I have a set over 240 cfm that I ported...
Not everyone running 11's with a small port 308 is a pro engine builder. Quite the opposite. But by all means stay where you are.
Have you ever ported a cylinder head let alone 318 heads?