Do you remember when classic Mustang enthusiasts said late-model 1979-93 Fox Mustangs would never be collectable?
Well, there’s nothing quite like the indigestion that comes from eating your own words. The 1979-93 Fox Mustangs are back and hotter than ever.
Why? They’re popular for the same reasons classic 1965-73 Mustangs were 30 years ago — nostalgia. They remind us of our youth. It’s time to reconnect with them.
Fox and SN-95 Mustangs are user-friendly rides to enjoy and cruise in the true spirit of Mustangdom, be it a 1979-93 Fox or a 1994-95 SN-95.
Building More Power in our Ford 5.0L
Nice thing about the Ford 5.0L pushrod small-block V8 engine is its simplicity. No overhead cams to sweat out. It actually has a distributor.
The small-block Ford V8, introduced in 1962 as the “90-degree Fairlane V8” displacing 221 and 260 c.i.d., enjoyed a long production life that spanned four decades making it one of Ford’s most popular performance engines ever.
We wanted to understand what we had under the hood of a dusty-dirty-forgotten 1989 Mustang GT convertible snatched from a San Fernando Valley driveway for $500.
When we put it on the dyno, the well-worn 5.0L High Output (H.O.) engine managed 220 horsepower and 230 foot-pounds of torque at the wheels — not bad when you consider how abused this engine was.
This means Ford’s tried and proven 5.0L engine makes 300 hp and 300 ft.-lbs. pounds torque at the crank from the factory. The seller included the car’s original unmolested 5.0L engine with the sale.
We put together a plan to make 400+ hp and 400 ft.-lbs. of torque at the crank by merging great engine building technique with terrific speed parts from Summit Racing.
The result was in excess of 400 hp and 400 ft.-lbs. of torque proven on the chassis dyno at Full Throttle Kustomz in Fillmore, CA along with a custom tune.
We wanted a good streetable Mustang with road manners that we could drive anywhere.
We looked to Air Flow Research (AFR) for off-the-shelf cylinder heads, Crane Cams for the bumpstick and valvetrain, Holley for induction, MSD for ignition, BBK Performance for innovative power adders, Fel-Pro for terrific gasket technology, ARP for fasteners, and Ford Performance Parts for an assortment of speed components.
Down under, we reached out to Eagle Special Parts for a 4340 steel crank, H-beam rods, and Mahle coated and forged pistons; and Centerforce for the Dual-Friction clutch and flywheel.
We unbuttoned the Mustang’s original 5.0L H.O. engine, which had a spun rod bearing and a damaged crank.
We hit pay dirt when we discovered that we had a standard bore block and that the heads had never been off. We took this original matching number 5.0L engine and hauled it to JGM Performance Engineering in Valencia, CA.
We’ve assembled a great formula for streetable/weekend racing performance — a balance of brute power on demand and civil street manners for the daily commute.
We wanted a smooth idle along with abundant power when the throttle was pinned. AFR asked us what we wanted in terms of horsepower, torque, and overall performance. Then — AFR went to work in its research and development lab fine-tuning a pair of custom AFR 185 “Renegade” cylinder heads for our blueprinted Summit Racing 5.0L small-block.
To get the desired compression, 10.67:1, AFR shaved the heads to achieve 48cc combustion chambers, then, massaged the ports and chambers along with a nice custom valve job with 2.02/1.60-inch intake and exhaust valves.
The 10.67:1 compression ratio was achieved with .041-inch thick Fel-Pro Perma-Torque #1135 head gaskets right off of the shelf. AFR enabled us to build a 400-500 horse small-block from a 4.030-inch bore and 3.000-inch stroke (306 c.i.d.).
We investigated what Crane had available for this application and came up with a nice grind from an off-the-shelf hydraulic roller with 110-degree lobe centers — .584/.550-inch intake/exhaust, duration at .050-inch 222/226.
For greater valve lift, Crane suggested its Gold 1.7:1 ratio roller rockers along with single-piece .080-inch wall thick hardened pushrods. We have a slightly lumpy idle, which is tolerable at the traffic light, and offers gangbuster power when the light turns green.
When you’re planning 400-500 hp, you want an engine that’s going to stay together at 6,000-6,500 rpm.
We grabbed an Eagle ESP Armor 4340 steel crank with a 3.000-inch stroke off the shelf with H-beam rods and coated Mahle forged flat-top pistons with valve reliefs large enough to clear our cocktail-table-sized 2.02-inch intake valves.
Eagle’s ESP Armor Plate ESP treatment is a revolutionary new surface finishing process developed exclusively by Eagle Specialty Products and is available from Summit. Eagle stresses that this is not a coating. The material you see is the same material on the surface you have always seen — just micro-finished to perfection.
Jim Smart is a veteran automotive journalist, technical editor, and historian with hundreds of how-to and feature articles to his credit. Jim's also an enthusiast, and has owned and restored many classic vehicles, including an impressive mix of vintage Ford Mustangs.