Joe Hutcherson's 1976 MGB with Chevy 4.3 EFI V6

Joe Hutcherson · 1976 MGB roadster

MG MGB

BritishV8: the site for enthusiasts of modified British sports carsas published in British V8 Newsletter, Volume XV Issue 2, September 2007

Read the full write-up at BritishV8: the site for enthusiasts of modified British sports cars ↗

Photo: BritishV8: the site for enthusiasts of modified British sports cars

A 1976 MGB roadster converted to a Chevy S10 4.3 V6 with EFI

Joe Hutcherson, with Terry Hutcherson, swapped a 1991 Chevrolet S10 4.3 liter V6 and its stock throttle-body injection into a 1976 MGB roadster. The job involved extensive floor, crossmember, and transmission tunnel fabrication plus a full air conditioning installation, and the finished car has covered about 5000 miles since completion. It is a useful reference for anyone tackling a V6 automatic swap with factory EFI and retrofitted A/C in an MGB.

Specs

As stated in the original write-up.

Engine: 1991 Chevrolet S10 4.3 liter V6, stock including original throttle-body fuel injection
Exhaust: Custom fabricated manifolds, 3 inch tube collector into two 2.5 inch Supertrapp mufflers
Transmission: GM 700R4 automatic, home-made driveshaft
Rear axle: Stock MGB
Front suspension: Stock MGB with spacers added above coil springs; Ford power steering rack retrofitted after initial completion
Rear suspension: Stock MGB plus home-made traction bars
Brakes: Stock MGB with cross-drilled rotors
Wheels/Tires: Stock
Electrical: Chevy S10 wiring harness and fuse block, electronic S10 Autometer speedo and tach
Other: Air conditioning added with large condenser and radiator, modified center console for A/C controls and automatic shifter, custom roll hoop, rubber-to-chrome bumper conversion
Completed: August 2002, about 5000 miles driven as of May 2007

Parts used

Parts named as used in the original write-up, grouped the way the Parts page groups them. Where one of the shops we index lists the same thing for this car, it is shown underneath with a link to the shop.

Engine 1

Chevrolet 4.3 liter V6 engine (1991 S10)Chevrolet
Stock engine used as the powerplant, retaining its original throttle-body fuel injection

Fuel & Ignition 2

Stock S10 throttle-body fuel injection systemChevrolet
Retained from the donor engine to run the V6 unchanged
In the shops
Jenvey Heritage Throttle Body Fuel Banjo Fitting ↗Racetorations· £35.20 GBP
Jenvey DCOE Throttle Body Air Horn ↗Racetorations· £30.00 GBP
Jenvey DCOE Body Throttle Linkage Kit ↗Racetorations· £134.00 GBP
Custom exhaust manifolds
Fabricated manifolds feeding a 3 inch collector

Cooling 1

Larger radiator
Installed with major front-end reconstruction to handle the V6 and air conditioning

Gearbox & Drivetrain 2

GM 700R4 automatic transmissionGM
Paired with the V6 and a home-made driveshaft
In the shops
Borg-Warner Type 35 Automatic Transmission Brake Band ↗Sports & Classics· $89.95 USD
Borg Warner Type 35/65/66 Rear Automatic Transmission Seal ↗Sports & Classics· $12.95 USD
BW-8 Automatic Transmission ↗Moss Motors – Triumph TR6/TR250· $0.00 USD
Home-made driveshaft
Fabricated to connect the 700R4 to the stock MGB rear axle

Suspension & Steering 2

Ford power steering rackFord
Retrofitted after initial completion to reduce steering effort
In the shops
EZ Power Steering Kit ↗Moss Motors – Triumph TR6/TR250· $2,702.99 USD
EZ Power Steering Kit ↗Moss Motors – Triumph TR6/TR250· $2,699.00 USD
EZ Power Steering Kit ↗Moss Motors – Triumph TR6/TR250· $2,349.00 USD
Home-made traction bars
Added to the rear suspension to control axle wrap from the V6
In the shops
Innovative Mounts Competition Traction Bar Kit - Black (92-00 Civic EG/EH/EJ/EK/EM, 94-01 Integra DC) ↗JDMuscle — Mazda MX-5· $393.65 USD
Innovative Mounts B-Series Competition Traction Bar for JDM/EDM RHD - Black (90-93 Integra, 88-91 Civic) ↗JDMuscle — Mazda MX-5· $367.41 USD

Brakes 1

Cross-drilled brake rotors
Fitted to the stock MGB brake system
In the shops
Brake Rotor Pair, Cross-Drilled and Slotted ↗Moss Motors – Triumph TR6/TR250· $131.50 USD
DBA Cross-Drilled and Slotted Brake Rotors (Pair) ↗Moss Motors – Triumph TR6/TR250· $237.00 USD
Drilled and Slotted Brake Rotor Set (MGB) ↗bpnorthwest.com· $98.99 USD

Body & Trim 2

Custom roll hoop
Added to the car during the build
Rubber-to-chrome bumper conversion
Bumpers converted from rubber to chrome style
In the shops
Chrome Bumper Conversion Kit with Rubber Tip Overrider ↗Moss Motors – Triumph TR6/TR250· $1,787.50 USD
Chrome Bumper Conversion Kit ↗Moss Motors – Triumph TR6/TR250· $1,418.75 USD
Chrome Bumper Conversion Kit with Chrome Overrider ↗Moss Motors – Triumph TR6/TR250· $1,418.75 USD

Interior 1

Modified center console
Reworked to add air conditioning controls and house the automatic transmission shifter
In the shops
ARE Center Console ↗Moss Motors – Triumph TR6/TR250· $105.25 USD
Center Console Lid Repair Plate ↗Moss Motors – Triumph TR6/TR250· $9.50 USD
Center Console Lid (MGB 1972-80) ↗Moss Motors – Triumph TR6/TR250· $120.50 USD

Electrical 2

Chevy S10 wiring harness and fuse block
Used to wire the swapped engine and electrical accessories
In the shops
Main Wiring Harness (Vinyl) ↗Moss Motors – Triumph TR6/TR250· $663.25 USD
Main Wiring Harness (Vinyl) ↗Moss Motors – Triumph TR6/TR250· $736.50 USD
Main Wiring Harness (Vinyl) ↗Moss Motors – Triumph TR6/TR250· $583.75 USD
S10 Autometer speedometer and tachometer
Electronic gauges fitted to match the donor driveline
In the shops
Tachometer or Speedometer Cable ↗Moss Motors – Triumph TR6/TR250· $17.99 USD
Glass-Tachometer or Speedometer ↗MGbits4U· £22.89 GBP
Opel Tachometer/Speedometer Cable (NOS) ↗Sports & Classics· $19.95 USD

Other 2

Supertrapp mufflersSupertrapp
Two 2.5 inch mufflers used in the custom exhaust system
Air conditioning condenser
Fitted alongside the radiator, requiring reconstruction of the front structure

Photos

40 pictures collected from the write-up, in the order they were posted, shown from BritishV8: the site for enthusiasts of modified British sports cars. A picture opens larger here, with the way through to the page it is on.

Joe Hutcherson's 1976 MGB with Chevy 4.3 EFI V6Photo: BritishV8: the site for enthusiasts of modified British sports cars

Chevrolet 4.3 V6 throttle-body fuel injectionPhoto: BritishV8: the site for enthusiasts of modified British sports cars

radiator shroudPhoto: BritishV8: the site for enthusiasts of modified British sports cars

custom center consolePhoto: BritishV8: the site for enthusiasts of modified British sports cars

custom exhaust manifoldPhoto: BritishV8: the site for enthusiasts of modified British sports cars

air conditioningPhoto: BritishV8: the site for enthusiasts of modified British sports cars

GM 700r4 automatic transmissionPhoto: BritishV8: the site for enthusiasts of modified British sports cars

fuel lines for EFI conversionPhoto: BritishV8: the site for enthusiasts of modified British sports cars

fuel filter for EFI conversionPhoto: BritishV8: the site for enthusiasts of modified British sports cars

custom traction barsPhoto: BritishV8: the site for enthusiasts of modified British sports cars

MGB on the rotisseriePhoto: BritishV8: the site for enthusiasts of modified British sports cars

painting an MGBPhoto: BritishV8: the site for enthusiasts of modified British sports cars

modified MGB front clipPhoto: BritishV8: the site for enthusiasts of modified British sports cars

MGB front fenderPhoto: BritishV8: the site for enthusiasts of modified British sports cars

custom MGB V6 radiator supportPhoto: BritishV8: the site for enthusiasts of modified British sports cars

highly modified MGB front structurePhoto: BritishV8: the site for enthusiasts of modified British sports cars

modifications for early-style turn signal indicatorsPhoto: BritishV8: the site for enthusiasts of modified British sports cars

modified front structurePhoto: BritishV8: the site for enthusiasts of modified British sports cars

MGB floorboard replacement/reinforcementsPhoto: BritishV8: the site for enthusiasts of modified British sports cars

modified MGB front crossmemberPhoto: BritishV8: the site for enthusiasts of modified British sports cars

steering rack mountingPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Modifications of the front suspension crossmemberPhoto: BritishV8: the site for enthusiasts of modified British sports cars

automatic transmission shifter mountingPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Mounting of the automatic-transmission shifterPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Modifications to the transmission tunnelPhoto: BritishV8: the site for enthusiasts of modified British sports cars

driveshaft tunnelPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Custom exhaust manifolds and pipesPhoto: BritishV8: the site for enthusiasts of modified British sports cars

exhaust pipesPhoto: BritishV8: the site for enthusiasts of modified British sports cars

heating ductworkPhoto: BritishV8: the site for enthusiasts of modified British sports cars

radiator mountingPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Radiator and air-conditioning condensorPhoto: BritishV8: the site for enthusiasts of modified British sports cars

air conditioning condensorPhoto: BritishV8: the site for enthusiasts of modified British sports cars

transmission selector indicatorPhoto: BritishV8: the site for enthusiasts of modified British sports cars

engine control unitPhoto: BritishV8: the site for enthusiasts of modified British sports cars

HVAC ductworkPhoto: BritishV8: the site for enthusiasts of modified British sports cars

air conditioning control panelPhoto: BritishV8: the site for enthusiasts of modified British sports cars

HVAC connectionsPhoto: BritishV8: the site for enthusiasts of modified British sports cars

air conditioning / heater fanPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Chevy S10 wiring harness and fuse blockPhoto: BritishV8: the site for enthusiasts of modified British sports cars

Chevy S10 fuse blockPhoto: BritishV8: the site for enthusiasts of modified British sports cars

How it was done

The conversion

Joe and Terry Hutcherson fitted a stock 1991 Chevrolet S10 4.3 V6 with its factory throttle-body injection into a 1976 MGB, paired with a 700R4 automatic transmission and a home-made driveshaft. The swap required strengthened floor pans, reinforced crossmembers, and a modified front suspension crossmember to accommodate the drivetrain.

Chassis and driveline fabrication

The transmission tunnel was reworked to mount the automatic shifter, and custom exhaust manifolds and pipework were fabricated to route spent gases into Supertrapp mufflers. Home-made traction bars were added at the rear axle to control wheel hop under the V6's power.

Cooling and air conditioning

Major reconstruction of the front structure was needed to fit a larger radiator alongside an air conditioning condenser. The center console was modified to house both the automatic shifter and new air conditioning controls, and the Chevy S10 wiring harness and fuse block were adapted to run the electrical system.

Later changes

After the car was initially completed, a Ford power steering rack was retrofitted to reduce steering effort. The car was finished in August 2002 and had been driven roughly 5000 miles by May 2007.

A summary in our own words. The full account, with all its detail, is in the original write-up: read it at BritishV8: the site for enthusiasts of modified British sports cars ↗