Horse Sense: Longtime readers may recall reading this story before. Swapstories are so popular we decided to rerun several in this issue.However, since we last ran this story, Doug Durham closed his business.The info in the story is still useful, of course.
The obvious question surrounding a V-8 swap into a four-cylinder Mustangis, why would you want to do it? After all, there are plenty of used 5.0Mustangs for sale in the paper and trader mags, so why screw around witha lame four-banger and go to all the effort of performing an engineswap? Well, there are two reasons. The first is obviously price. Lesser'Stangs are much cheaper to buy than comparable 5.0s. In fact, whileshopping for a four-cylinder car to use for a big-block swap, we'vefound acceptable ones as cheap as $200! But, after buying a decent 5.0engine and trans, and all the parts required to perform the swap, thecost factor is almost a push. There must be some other attrac- tion,right?
Here's one you might not have thought about--level of abuse. Becausethey're so much fun to drive hard, 5.0s are driven hard--real hard. Andbecause of that, the torque boxes get torn up, the body flexes andsometimes cracks, and overall, the car just gets beat on. And that'sjust the chassis. It's really a crap shoot whether or not the engine ismortally wounded. Now think about the typical drivers of four- orsix-cylinder Mustangs. They ease away from stoplights, gently slow downfor corners, and never, ever do five-grand clutch drops. Essentially,they never do anything to stress the car. They're wimps, by and large,but that means the basic cars are usually sound (assuming they haven'tcrashed them). And even if they do drive these cars hard, an 88hp 2.3Lis unlikely to hurt the torque boxes or twist anything more sturdy thana cereal box.
Doug Durham built 5.0 engines...
Doug Durham built 5.0 engines for Blue Oval Racing and other clients.Behind his shop were various Fox-bodied Mustangs.
Swapping a 5.0 into the space once occupied by a four- or six-cylinderis not a huge deal, but it requires some effort in obtaining all thecorrect parts, especially the little bits you wouldn't normally thinkof. In researching this story, we went to some experienced folks inTexas, including Doug Durham, who built 5.0 motors at Doug's Motors ineast Dallas, and Bill d'Happart, who does the swaps at Blue Oval Racingin Rowlett, Texas.
Once you've found the four- or six-cylinder car, the next chore is tofind the engine, the trans, the 8.8 rearend, the 5.0 wiring harness, theMAP sensor, the computer, the vacuum canister, and a dozen other parts.Normally, the easiest way to do this is to buy a complete wrecked 5.0.Concerning the transmission, this story will show a five-speedapplication; if you want to use an automatic, it's much easier to startwith an automatic car so you don't have to deal with swapping the pedalsand such. As for the rearend, you don't have to get an 8.8 right away,but be aware that the four- and six-cylinder cars have the weak 7.5,which will not live long behind even a stock 5.0.
Doug stocked several donor...
Doug stocked several donor cars behind his shop, such as this red '80model four-cylinder. Its cost: $200!
Computer Compatibility
| Model Year | Use |
| '86-'88 | Any '86-'88 computer |
| '89 | '89 computer only |
| '90-'93 | Any '90-'93 computer |
Crossmember Guide for True Dual Exhaust
| Models | Engine | DH Crossmember? |
| '79-'85 | All | No |
| '86-'93 | V-8 | Yes |
| '86 | Four-Cyl | No |
| '87-'88 | Four-Cyl | Some |
| '89-'93 | Four-Cyl | All |
The purpose of this story is to show how to install a 5.0 EFI engineinto a '79-'93, four-cylinder Mustang. It's not a step-by- step how-to,but rather shows what parts you'll need and how to find them. Good luck!

Likewise, Bill d'Happart stocked...

Likewise, Bill d'Happart stocked four- cylinders for future V-8conversions. Here's a pair of '88 LX coupes, one with a five-speed andthe other with an automatic. Both run. The blue LX at the top has a dentbehind the passenger door. It cost $500. Bill paid $725 for the blackfour-cylinder coupe, which was in better condition. It has air and thepaint will buff out fairly nice.

Bill harvested parts from...

Bill harvested parts from wrecked 5.0 Mustangs for his V-8 engine swaps.You can do the same thing and save multiple trips to the junkyard (andmoney) for the many parts needed. You might find a wrecked 5.0 with theengine intact for $1,500 to $2,000. If you already have a 5.0 engine,another possibility is to buy (for about a grand less) a wrecked 5.0without the engine.

Here's a look at the four-cylinder...

Here's a look at the four-cylinder engine bay of the black '88 LX coupe.The V-8 fits using the stock four-cylinder K-member and V-8 motormounts. Stock V-6s also share a K-member with the V-8, while in-linesixes do not. Suspension geometry is common, no matter the engine. Airconditioning parts won't swap from one engine to the next.

Bill harvested parts from...

Bill harvested parts from wrecked 5.0 Mustangs for his V-8 engine swaps.You can do the same thing and save multiple trips to the junkyard (andmoney) for the many parts needed. You might find a wrecked 5.0 with theengine intact for $1,500 to $2,000. If you already have a 5.0 engine,another possibility is to buy (for about a grand less) a wrecked 5.0without the engine.

With the passenger-side front...

With the passenger-side front fender removed, we can see two vacuumreservoirs mounted to the upper structure. Both V-8s and fours have thelarge bulb, which supplies vacuum for the heater and air conditioningrouting under the dash. The small canister is unique to the EFI V-8 andstores vacuum for engine functions.

The small canister has a vacuum...

The small canister has a vacuum hose that routes through the sidestructure of the Mustang and into the engine compartment. Notice it hasfour passages for vacuum. One line goes to the back of the intake, oneline goes to the EGR, and the other two lines route to the air pump.