I'm running a SBF with sync'd Holley 390's (4160 series) on a Weiand #1988 Street T/R intake, with hi-po '66 289 heads at 10.5:1. My cam is fairly mild. I'll be building out to 331 soon (yay, eBay!) and will upgrade the cam to a Crower Level 3, but intend on keeping the dual quad tunnel ram setup.

The biggest problem was having to rebuild the carbs completely to get them to sync. Now that that's done, it runs killer. Idles sweet, goes fast, sounds great, and all that engine is a real head-turner sticking out of my little car. Runs on cheap pump gas.

Most of the negative things I was told about running a dual-quad tunnel ram seem to only apply to overcarbed engines. If you're running 390's, you should be streetable no problem.