340 Vs 360
Who's saying otherwise? Certainly not me.
Really, so if I add a 4" stroke to my 318 I'll end up with less horsepower than I started with?
I'm going to have to disagree there.
Build that 318 with a 4 inch stroke and it will make more power than it did BUT you won’t have enough cylinder head on it. It’s IMPOSSIBLE.
Think about it.
The W2 head was developed in the early 1970’s and was for 330 inch drag stuff and 355 inch circle jerk stuff.
And for those displacements and rod to stroke ratios they were too small. They take an incredible amount of work.
So you tell me, how is that a good thing using a 4 inch stroke and being THAT cylinder head limited because I’m thinking if you are starting with a 318 you won’t front for W2 heads?
You will be severely RPM limited unless you run outrageous cam timing.
Here is an example. This may help you understand.
In 2000 I built a 408. It had fully ported Edelbrock heads and a fully ported Strip Dominator. IIRC it was 10.8:1 but it could have been a skosh higher. It had a custom Cam Motion hydraulic roller that IIRC was in the low 240’s @ .050 and was in the low to mid .500’s for lift. It had a 750 Holley and 1 7/8 headers.
And guess what? At 5200 it was OVER. Used up. No more. It’s tongue was out and bloody.
We could have used more cam but then it would have needed more RPM (which is taboo) and it would have lost some bottom end (another fallacy).
It made 545 HP and I forget the TQ because who cares? It was close to the HP or maybe it was more.
Here‘s the real pisser. I would have built it with a 3.58 stroke (or maybe the 3.79 stroke as either would have been better than the 4 inch arm) and instead of the anemic 5200 RPM I would have turned the 365 inch (3.58 stroke) 7200 or the 387 incher (3.79 stroke) 6500ish and I could make the same 545 HP but at the higher RPM and the smaller engine would kick the living **** out of the 408. Every. Single. Time.
Understanding the math of it is relatively simple. Dealing with the facts is the hard part evidently.