Reply to "Wide and Flat Torque Curve"

28 degrees total timing is consistent with controlling the combustion chamber pressure to avoid detonation of US 93 octane pump gas.

If you were detonating the fuel at somewhere in the 30 to 36 degree range and you lowered the advance to a point where it no longer detonated, you would show an increase in both hp and tq.

That is an indication that the engine was detonating and there were no other obvious indications.

A big engine might not show it except in the dyno numbers, particularly if the combustion chambers had been modified.

The controlling factor to the entire experiment is the octane of the fuel used. You must determine at what pressure the 93 will detonate and then arrive at solutions on how not to exceed that.

Static compression ratio, total timing and camshaft timing are all major contributing factors to that.

If you can control detonation with chamber design alone, without a computer control of the ignition and tailoring those factors to comply to the fuel requirements, then you had better patent this chamber design because you have change the laws of physics and you may have also discovered Warp Drive for the Enterprise?

Changing to a single plenum intake manifold would change the characteristics of the engine and is just a tuning choice.

It is entirely possible that this dual plane will out perform the single plane entirely. Especially since this engine seems to be limited to 6700rpm. Particularly if it has been modified and flowed itself to compliment the air flow characteristics of the heads and induction it is mated to? I'll bet this one was seriously flowed before the dyno test?

The main advantage to the single plane would be above that.

The Yates and Nascar "Ford" single plane manifolds were created to yield hp gains up to 9200 rpm. That right there should be an indication of which is the "better" intake to use for this application.

Anyway you look at this, this is really a hell of an engine.

It out preforms the race 427 Fords at every level at a lower cid number.

The 427 Ford is now quite expensive to build. I don't know if this Australian Cleveland is going to have any price advantage. Looks like a dollar monster to me?

I mention them simply because I use those as the standard by which I measure BB performance and this 393 like it or not is a "BB" in that sense.

BUT there are other issues to consider with it. First of all, it may not necessarily been built for a Pantera.

As such to run it hard in one, you have to consider the longevity of the ZF with it.

I suppose the term "running it hard" now has to be defined as well. Looking at those torque numbers, it is running hard just idling, sitting there doing nothing?

Second as has been mentioned here, does it have the same small block "rev-ability"?

It would appear from the numbers posted that it is just a big bully that is going to break traction consistently just off of idle?

To me, that isn't what I like in an engine.

This really is just a bench racing post with debates over what taste in an engine should be and whose manhood is bigger then the other guys?