351W F.O. changed to 289

[blykins]

I have a question....not trying to argue....but I'm trying to see where my math is off.

You're saying that it takes 2 revolutions for all 8 cylinders to fire.

If you're turning a steady state 6000 rpm, that means that the total of the 8 cylinders have fired 3000 times....correct?

If I am correct there, then each cylinder has fired 375 times in one minute. By that logic, each cylinder has fired roughly 6 times in one second....not 50.

Multiplying 6 times in one second by 8 cylinders would be 48 times per second....If that's the case then.....

It would be .020 seconds between firing. In the old firing order 5 would fire .020 seconds after 1. In the new firing order, 5 would fire .1 seconds after 1.

I think a valid point was made. It's not necessarily the force of the cylinders firing consecutively, but I'm sure you know how natural frequencies eminate. Also, there is a valid point above, with two cylinders following each other, two cylinders are going to be on power stroke at the same time....trying to drive that crank through the main cap. And you know, if they were in perfect sync, it may not be that bad....but they're not in perfect sync.....which adds a lot of imbalance and vibration on that front bearing.

I don't know....I think it's something worth considering. However, if the old firing order cam made so much more horsepower, I would think more racers would be using them and this would be more of a widespread knowledge.

One of the engine builders here at work said that there is a variant of the GM firing order that allows more horsepower to be made.....and it does it because the old firing order has two cylinders right next to each other firing one after the other. This was disrupting the intake charge and basically had two cylinders fighting for the same intake pulse.

It's probably some good things to consider....but with testing, proof, and tact.