Ever heard the saying, "You can't have your cake, and eat it too." In car speak that translates into, "If you want a lot of power, you will have to sacrifice drivability and fuel economy." Granted, most diehard Mopar fans are used to the trade-off, and refuse to give up horsepower for pretty much anything. We've simply learned to cope with all the various drivability issues associated with vintage high performance powerplants. There may even be a little pride connected with how "radical" an engine you are able to manage on the street.

But unless you have been living under a rock for the last few years, you've noticed that Chrysler is producing some pretty hot engines that not only rival the vintage iron for power, they also pass emissions, get decent fuel economy, and run smooth enough that your grandma can take it to church on Sunday and not think that it's anything special.

How are they doing it? Well, you know this too. It's no secret. It's computer-controlled, electronic fuel injection. Certainly there have been other advancements in engine design, but they all work because the computer can precisely control fuel and timing (and a whole lot of other things in the car) at every engine speed, load condition, and temperature.

So what do you suppose it would be like to drive a 500 horsepower big-block that doesn't have any flat spots in the power curve, never loads up in traffic, and always starts quickly, runs the same whether it's hot or cold out, and gets double digit fuel economy? We thought we'd find out if we can have the proverbial cake and enjoy the frosting too.

Our test vehicle is a '68 Hemi Dart replica that's being built at Muscle Car Restorations in Chippewa Falls, WI. The owner doesn't just want a really cool car, he also wants hassle free driving-to be able to get in it and go any distance under any condition. While there are a number of quality EFI products on the market, for this test we will be working with a FAST (Fuel Air Spark Technology) system. The FAST system is extremely flexible and can handle virtually any combination you can dream up. All you need to do is let them know which engine you're running, the approximate power level you expect, and what ignition system you will be using, and they can set you up with everything you need.

In this case, that includes the FAST ECU, a FAST dual-sync distributor, a throttle body, a set of 42-lb/hr injectors, and the wiring harness to tie it all together. There is also an idle-air control motor, a MAP sensor, a wide band O2 sensor, a throttle position sensor, and air and water temp sensors. Of course you need a place to fit the injectors so an Indy single-plane intake and valley cover will also be used (though your stock intake could be fitted for injectors if you'd like). FAST also includes their C-Com EFI Software and a rather in-depth training DVD.

Our engine is a Hemi crate motor that will be used in its stock configuration except for the Indy intake manifold. But before we hooked up the EFI, we broke the engine in with a stock intake and a 750 Holley so that we could both be assured of a clean break in run, and provide some base dyno numbers we could use for comparison after the EFI install. Box stock, our Hemi made a 482 horsepower and 469 lb/ft of torque.

Once the Hemi cooled down, we swapped intakes and hooked everything up. It really couldn't be much easier. Everything is a simple bolt on with the exception of the O2 sensor. You'll need to weld a bung onto one of your header collectors in order to mount it. Connecting all of the wiring is also easy because all of the connections are clearly marked. It's truly plug and play.