I agree with most of the things you say, but not on this.
I think that if you delve into this, that you will find a different conclusion.
>>Detonation is almost always the result of a runaway chamber temp;
control that chamber temperature/eliminate the detonation.
>>I would say, that for a streeter, SCR means as good as nothing.
Scr is just a tool to help us achieve certain pressures/DCR targets that are known-to-be-detonation-free.
>>By empirical testing, we know that we can run a DCR of 8.0 on our pumpgas with iron heads. History has shown, that it almost doesn't matter how poorly you screw that 8.0DCR thing together, you'll be able to tune it to run on pumpgas.
>>And also by empirical testing, we know that we can run a DCR of ~9.0 with alloy heads, detonation-free on pumpgas; again, almost no matter how poorly a guy screws that together.
Lemmee flip it back to you, in a couple of different ways.
1) After I installed the AirGap intake, onto my alloy-headed 367, and routed fresh cold-air into the airhorn, I was able to up the minimum coolant temp to 205* from 185, and add two degrees of Power-Timing (to 34*), without detonation, on 87E10(R+M)2.
Same 11.3Scr/9.0DCR/195psi,engine. The difference was the reduced chamber temperature, due to the reduced induction temperature.
2) Using your example;
I will use the example of a
[email protected], for ease of calculations, and set the elevation to 500ft.
Install a small cam with an Ica of 60*; the Wallace calculator predicts a pressure of 165psi/DCR of 8.16. With iron heads, this is on the upper edge of the pressure limit for our 91 gas. With open chamber heads, a standard non airgap intake, and hot under-hood air, this could be a tough tune.
But it's not the pressure by itself that sets the limit; rather, it's the in-chamber temperature-rise, caused by the pressure-rise. Reduce the inlet air temp, or the coolant temp, or some combination of the two, and it will run detonation-free.
The problem is this; most guys will not cut a hole in their nearly impossible to replace hoods, which then makes it very difficult to reduce that inlet air temperature and/or the temp of the intake manifold.
>Now take the above 9.9Scr/360 engine, and put the next bigger cam into it which will increase the Ica by ~3 degrees. Now the Pressure is predicted to drop to 160psi/DCR of 8.0. This will reduce the tendency to detonate, with the hot intake air. Or, just re-time the earlier cam to 3* later, same result.
I'm pretty sure you know all this,
so IDK why you would say
"CCP means nothing",
If that was true, then we'd all just run 8/1 engines no matter what cam is installed...... and so never have detonation issues.......am I right?