I have done quite a bit of racing with my mustang, both with E7's and trick flow and have had them on the dyno. It doesn't matter to the 'combustion chamber' what your cam is timed at but does matter when you get spark. The TFs are much more effeicient and require less timing and with the factory EEC IV mine always made best power at 14* advance

 

Not sure what you're saying here, but the crank keyway is at #1 TDC. When you align the crank key at 12 o'clock, the #1 piston is at TDC

 

Mine seems to pull better upstairs @ 13*. I am still tweaking the tune, but it feels pretty good right now, even in this hot weather. I hope to get it back to the track soon just to see how much it helped.

 

Baddad, what I mean is that looking at the front of a bare crankshaft one will see that the keyway is located about 45 degrees clockwise to the first (#1) throw.

 

Ok, that puts it's location at 12 o'clock, so that the #1 piston is at TDC. Which is as it should be.

 

I had to replace the water pump on my engine last week, and noticed that the front cover gasket has been leaking for a while. So I've been running on low coolant for I don't know how long, even though the temp gauge showed "normal" temps. Today was the first time that I got the system fully burped after replacing the pump and all the gaskets, and noticed the steady state temp reading was slightly lower than before the fix; it's now right on the first quarter indicator, vs between 1/4 and 1/2 before.

So I took the car out for a really long ride, up some steep grades, accelerating as hard as the engine would go, and magically, heard no detonation. Could I have been overheating the engine for all the time that it was low on coolant, and that was what was causing the detonation I had been experiencing? More driving will tell.

In answer to your question, when it was detonating, it seemed to start at full load as the engine reached 4000 rpm. Since I knew that was bad for the engine, I usually let off at that point, so never found out whether it would continue to do it past 4000 rpm. And the highest grade gas that's readily available around here is 91 octane. I've heard that some stations may still carry 93, but I haven't seen them recently.

 

Running warmer on the temps will increase the tendency to detonate.

 

Yes, you could have had some hot spots in the heads causing detonation. Mine is hard to burp too sometimes.

 

I'll try to insert the picture:



Hey, it works!

Note that the #1 journal is straight up (TDC) while the damper key is about 45 degrees clockwise.

 

When the #1 cylinder is at TDC, that crank throw is canted counter clockwise about 45* and the keyway it straight up at 12 o'clock.

 

That is correct.