[Barry_R]

I'll echo a lot of the comments.

The most cost effective budget 390 I would spec for a Cobra would have a freshened up stock bottom end with a set of off the shelf Edelbrocks, an RPM intake with a 750, a Duraspark ignition, and a shelf Comp cam. Cheap to build, would drive just fine in a light car, and would have enough of the external cosmetics of a 427 for shows.

A "funner" version of the 390 would use a 4.250 stroker package, a Comp 282S solid cam and the required hardware, and tuning up the heads a bit. Still reasonable in cost - but more power by a bunch and it'll have that desireable solid lifter sound.

Once you go from a 390 to a 427 of any sort you leave "budget" behind and instead seek value - or glory.......