Building 400hp Into A 5.0L Small-Block Engine - Down-Low 5.0

How To Make (Almost) 400 HP For (Almost) $1,000.

By Richard Holdener

Is it really possible to build...

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Times are tough for many Mustang enthusiasts. In these uncertain economic times, we are forced to watch every penny, even though maximizing power is always high on the priority list. We all crave more power and better handling, but who has the big bucks for exotic parts? When times are tough, trade offs become necessary and in some cases, this involves trading expense for either knowledge (of the sort you find in the pages of MM&FF) or good old-fashion elbow grease.

For this engine build, which we'll call "Down-Low 5.0," we traded both. The premise or recipe was a simple, albeit popular, one. Take one 5.0L Ford and select the most cost-effective components in order to achieve our seemingly conflicting goal of power and economy. On the power side, we selected 400 hp as an impressive but reasonable output for our small-block 5.0L Ford.

Building a 302-inch small-block to produce 400 hp is really no big deal, but doing it for what amounts to chump change is decidedly more difficult. This meant building our 5.0L with a ceiling of just $1,000. Given the fact that $1,000 is less than the typical cost of a set of aluminum cylinder heads, reaching 400 hp for a grand total of $1,000 looks pretty impressive, not to mention somewhat difficult. Now let's throw in the fact that the $1,000 price tag must not only include the cost of said aluminum cylinder heads, but the entire 5.0L engine to boot. Have we lost our minds?

A little recon and planning...

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Naturally the 400 hp motor was not going to be some off-the-shelf crate motor assembly, unless you count the shelf at your local wrecking yard. Remember, we said that it might be necessary to trade cost for some elbow grease. In this case, the elbow grease came in the form of some computer legwork through the local sites for Craigslist and Recycler, as well as a few trips to a nearby wrecking yard.

Calling first, we found a few yards that offered complete motors for just $200 (plus a core of $45). Of course, the $200 motors were still installed in the vehicle, so this meant trading elbow grease for the additional cost savings. Always up for a quickie R&R procedure, we ventured off to our favorite Pick-A-Part in search of a low-buck but hopefully well-running 5.0L. Believe us, running motors (even good running motors) are out there for the taking. Given the sheer production numbers, this is especially true of 5.0L Fords. As luck would have it, the local Pick-A-Part had special sale weekends, when everything in the yard was 50 percent off. This brought the sale price of our used 5.0L down to just $100 (plus core). Available in both cars and trucks, our only concern was to locate a good-running 5.0L motor with everything intact. Though we would be replacing the fuel injection with carburetion, the factory injection system would help serve a later purpose.

Here are a couple of tips that might help you separate a usable junkyard 5.0L from the rest of the junk. First off, make sure that the motor has everything present that you will need to install in your vehicle. In most cases (like ours), the cost of the motor included everything from the air filter to the oil pan, the fan to flexplate (or flywheel). This also included things like the motor mounts, starter, and all of the accessories, though none of these would be run on the engine dyno.