Dynoed my 427so Cobra today.... interesting to say the least!

[ByronRACE]

OK, vacuum secondaries. I'll buy that.

The engine is running great; and you have a point...if you're happy with how it goes down the road, there's not much to gain (except risk) by increasing your RPM limit. I'm certain you have enough power/torque to scare yourself, so take the next suggestion with a grain of salt.

If you're not comfortable running the engine up to where it's currently making the power, consider a cam change. By shortening the duration of the cam, you will increase the area under the torque curve in the region you are comfortable running it, while at the same time creating a "natural" rpm limit. The engine will peak lower and make more torque, the power will go peak and flat sooner, and you won't be as tempted to keep your foot buried as the engine soars into the rpm range you're not wanting to run in. Right now you have a 7000-7500rpm engine and I'm sure it's pulling like a freight train right up to where you abruptly bump the limiter, leaving you with the feeling that there's a ton more up there if it were allowed. If that's not what you want, a cam change will give you a 6000rpm engine and a more natural feeling as you approach the rpm limit. Less duration will smooth out your idle as well. Depending on your taste, this may not be desirable. Part of a cobras personality is the idle note/beat.

There's nothing wrong with running it just like it is. You probably can't connect more torque anyway...so its pretty much academic, take it for what it is. I don't think there's a thing wrong with the way your engine behaves. I bet it's a blast.