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Need a V8 ? A quick guide to getting more power.
A basic 302/5.0 or 351W swap should take 50-70 hours if using the components listed below. Before starting a conversion, we recommend that you check local and state vehicle regulations to insure the modifications are legal. James Duff Inc cannot be held liable for any vehicle modifications since all conversion components are intended for off-road use only. See inside back cover of our catalog or website for warranty information.

When converting your Ranger or Bronco II to a V8, many of your stock components can be reused. However, it is easier and cheaper to purchase a complete "take-out" engine from a wrecking yard that already has the necessary components and brackets. If you cannot find one of these motors, we have provided a list of accessories and brackets to assist you with your conversion. You need a belt system using three belts to gain sufficient radiator clearance.

There are 3 popular options for engine swaps:
Carbureted 302: For '83-85 trucks with the carbureted 2.8, this is the easiest swap. On later models, it is nearly impossible to pass emissions with this setup. Refer to the following information for the modifications necessary for installation.

4.0L V6: On '86 and newer 2.9L V6 equipped vehicles, this is essentially a bolt-in swap. The 4.0 engine control computer, engine wiring loom, cooling system, and transmission should all be swapped in. This engine makes 170 hp, and can be upgraded with a Duff Power Chip, a free flow air filter, and even a supercharger.

5.0L V8 (Fuel Injected 302): On '86 and newer 2.9L V6 equipped trucks, swapping in the 215 hp 5.0L is similar to the 4.0L swap, in that you'll need to take the engine control computer and engine wiring loom from the donor vehicle. The modifications necessary for installation are mostly the same as the carbureted 302. If all emission equipment is retained, most states will accept it as emissions legal.

It is possible to swap in a 351W with many of the same components as the 302, but tight clearances make this much more difficult.

The original Bronco II and Ranger transmissions are too weak to withstand V8 power, and must be swapped for a heavier duty transmission. You have the option of changing your Manual truck to an automatic, or vice versa at this point.
In '83-'84, some vehicles came with a C5 automatic. In these vehicles, a V8 torque converter and bellhousing can be installed on the C5, though we suggest buying a stronger C4 originally used with a V8. Then have the C5 main shaft and tailhousing installed in the C4. A used C4 trans should cost between $75-$200.

There are two different belt systems, serpentine and "V" belt. Your pump should have an intake spout on the driver's side to match our radiator. The serpentine belt is reverse rotation, so you must keep the belt system your pump came with.

You can use your stock power steering pump by using the correct brackets, found on most Ford passenger cars, 1978-86. You need the correct V8 pulley for proper belt alignment. Original length hoses can be used on most conversions. For your convenience we've provided the Ford part numbers below. 2wd will need to modify a V8 bracket to fit.
Ford P/S Brackets........#E7TZ-3C511-A
Ford P/S Pump.............#E6SZ-3A674-B
Ford P/S Reservoir.......#E1FZ-3A697-A

Your stock V6 alternator can be kept by using the correct V8 pulley, alternator bracket and adjuster. If you are replacing a 4 cyl. engine, you should purchase a V8 alternator to provide the correct amperage. Ford Alternator Mounting Bracket...#E7TZ-10A313-B Ford Alternator Adjuster Bracket....#E6AZ-2888-A

If your vehicle has air conditioning and you wish to keep it, the heater box on the firewall will need extensively cut, though a body lift helps reduce this. The stock compressor may be used if you can find V8 mounting brackets. The wiring and hoses may need extended to reach the new compressor location. The AC condenser must be relocated to the front side of the radiator to clear the fan. The center vertical bar in the core support must be cut out to make room.

On carbureted V8s you must use an in-line electric fuel pump with a 5-7 psi rating. In most cases, a mechanical fuel pump will interfere with your steering box. If your vehicle came with electronic fuel injection, you have an in-tank fuel pump with a 40 psi rating. A regulator must be used to reduce pressure to 5-7 psi. If a regulator is unavailable, you need to remove the in-tank fuel pump and install an in-line electric fuel pump. On fuel injected V8s, you can retain the stock in-tank pump. If you install a highly modified engine, you may need to upgrade to a more powerful pump to supply more fuel pressure.

The starter motor, flywheel, bellhousing, and torque converter (or clutch) are a matched set. V8's in F-series came with 168 tooth flywheels which are larger and harder to fit around the firewall. The 157 tooth flywheel from passenger cars is smaller and easier to fit. It is important to check your flywheel and starter for proper engagement before installing the engine.

Your firewall and floorpan area is narrow and may need some slight modifications. We suggest using a 14" torque converter and bellhousing to make clearance. Otherwise, a 3 lb sledge hammer can make enough room. The body seam between the floorpan and the firewall must be bent over. In some instances, additional clearance may be needed near the bottom corners where the firewall and the floorpan meet. The heater box will need to be trimmed slightly and patched to clear the valve cover.

When converting to a V8, you can use the stock V6 temperature and pressure gauge sending units. If your vehicle has a mechanical tachometer, you will need to have it re-calibrated for the new engine.

Most swaps do not require the use of a suspension or body lift. However, a 2" body lift can greatly reduce the amount of firewall, heater box and floor pan modifications. See the Bushing section for body lift information. Reinforcing the front suspension with a suspension lift or double shocks is highly recommended.

Front: The Dana 35 from 89-97 4.0L Rangers and 91-94 Explorers is the easiest upgrade. It bolts into the same mounting points as the Dana 28, but does require some driveshaft modifications. We also offer the components for swapping in a Dana 44 solid axle from an Early Bronco. Check the Solid Axle category for these parts.

Rear: For Rangers, the 8.8" rear axle from '89-97 Rangers is a bolt-in, with some driveshaft changes. For Bronco II's, the same axle can be used, but the spring perches have to be relocated. The 9" is also a good choice, just be sure to check it for the correct width before installing. However, most 9" axles have a 5x5.5 bolt pattern, which will need changed to 5x4.5 to match the front axle.

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Water Pump Bypass Hose V8 Engine Conversion 90° thermostat Ford Small Block
90° Water Pump Bypass Hose, V8
Our Price: $11.85

Water Pump Bypass Hose with a 90° bend molded in to go with our 90° Thermostat for all 289/302/351W V8. Necessary for most Bronco II, 83-97 Ranger or 91-94 Explorer V8 Conversions.

K&N Air Filter Cleaning/Recharger Kit
K&N Air Filter Cleaning/Recharger Kit
Our Price: $15.00

Kit contains K&N air filter cleaner and air filter oil for cleaning any K&N Air Filter. Restores air flow efficiency so your K&N air filter performs like new!

V8 302 5.0 efi Engine Conversion Upper Radiator Hose Ford Bronco II Ranger
V8 Upper Radiator Hose Bronco II, Ranger
Our Price: $25.25

Upper Radiator Hose to go with our Aluminum Radiator on a V8 conversion in a Bronco II, 83-97 Ranger or 91-94 Explorer.

V8 302 5.0 efi Engine Conversion Lower Radiator Hose Ford Bronco II Ranger
V8 Lower Radiator Hose Bronco II, Ranger, Explorer
Our Price: $25.25

Lower Radiator Hose to go with our Aluminum Radiator on a V8 conversion in a Bronco II, 83-97 Ranger or 91-94 Explorer.

V8 302 5.0 efi Engine Conversion Upper Radiator Hose Ford Bronco II Ranger
5.0 Upper Radiator Hose for Serpentine B2, Ranger, Explorer
Our Price: $25.25

Upper Radiator Hose for our Aluminum Radiator with a 5.0 conversion in a Bronco II, 83-97 Ranger or 91-94 Explorer with a Serpentine Belt System.

Stage 8 Header Collector Exhaust Bolts V8 V6 6 cylinder 289 170 351w Ford
Stage 8 Collector Bolts (6)
Our Price: $29.95

Ordinary Header bolts can be a real pain to keep tight due to the expansion and contraction that headers go through. No one likes getting in there and busting their knuckles if they don’t have to. We swear by these (not at them)! They use a patented locking system that won’t come loose.
90° Thermostat Housing Bronco Ranger Explorer Thermostat housing 90° outlet Early Bronco, Bronco II, 83-97 Ranger 91-94 Explorer V8/5.0 Conversion
90° Thermostat Housing
Our Price: $29.95

Thermostat housing with a 90° outlet for your 289 302 351W Small Block Ford V8 in Early Bronco, Bronco II, 83-97 Ranger or 91-94 Explorer V8/5.0 Conversion.

Lokar Rectangular Shifter Boot & Stainless Steel Bezel
Lokar Stainless Bezel & Rectangular Shifter Boot
Our Price: $36.95

Set includes black vinyl boot, foam rubber seal to eliminate air flow from the floor through the boot, polished stainless ring and stainless screws. Outer dimensions 6.75" x 5.25" Inner dimensions 5.25" x 4".

Valve Cover Gasket Perma Dry Ford 289/302/351W Gaskets 1966-77 Classic Early Ford Bronco
Valve Cover Gasket Perma Dry Ford 289/302/351W
Our Price: $39.95

You may never have to replace your gaskets again! These reusable heat resistant silicone gaskets are quick and easy to install without adhesive. No mess to scrape up and they last up to 5 times longer than cork/rubber. Metal torque limiters prevent overtightening. Center steel reinforcement provide shape, making them easy to install.
Lokar Braided Stainless Throttle Cable Kit 94-95 EFI Satin Midnight Black Billet
Lokar Braided Stainless Throttle Cable Kit 94-95 EFI
Our Price: $47.95

All Lokar Hi-Tech Throttle Cables are available in either stainless steel braided housing or black stainless steel braided housing. They are designed with a specially extruded liner for extended life of the cable – not to be confused with ordinary braided brake hose. Cables are equipped with aluminum fittings and aluminum ferrules to eliminate fraying. "U-Cut-to-Fit" outer housing is 24" in length with a "U-Cut-to-Fit" stainless inner wire. Custom lengths available upon request. These cables are Bronco friendly and attach directly to the stock Bronco throttle pedal assembly. Kits complete with installation instructions. Works on all carbs, 86-93 ford EFI and aftermarket fuel injection systems. Note will also need the #2341 bracket.