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Simon Austin's 1977 MGB with Rover SD1 V8

Simon Austin · 1977 MG MGB Roadster

MG MGB

BritishV8: the site for enthusiasts of modified British sports carsas published in British V8 Newsletter, Volume XIV Issue 3, December 2006

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 1977 MGB roadster converted to a Rover SD1 3.5 V8

Simon Austin spent four years turning a rust-free, late-model California MGB shell into a V8 roadster using a rebuilt 1980 Rover SD1 engine and five-speed gearbox. The build covers a rubber-bumper to chrome-bumper conversion, a Sebring fender flare kit, a custom hood scoop, and a reworked interior with Miata seats and hand-made white-face gauges. It is worth reading for the detailed problem-solving around air filter clearance, header fitment, and ride height.

Specs

As stated in the original write-up.

Engine
1980 Rover SD1 3.5L V8, rebuilt to stock specs, remote oil filter
Intake
Edelbrock Performer intake, Edelbrock 500cfm carb with re-jetted needles/jets, K&N filter with Extreme top
Exhaust
RV8 headers, ceramic-coated, 2.5 inch stainless steel single-pipe system
Ignition
Buick distributor, Pertronix ignition, MSD ignitor box and tachometer adapter
Cooling
Custom 4-row radiator (stock width, 20 inch tall), two rubber-bumper electric fans, stainless articulated hoses, Rover water pump
Transmission
Rover SD1 5-speed (LT77)
Rear Axle
Stock MGB axle with 3.07:1 gears
Front Suspension
Stock rubber-bumper setup with lowered springs, V8 bushings, new lever dampers
Rear Suspension
Reverse-loop springs (part MGS 40721), new bushings, original lever dampers
Brakes
Front: stock hubs/calipers, cross-drilled/slotted rotors, EBC Greenstuff pads. Rear: stock drums, new shoes. Stainless braided lines, converted to non-servo system
Wheels
Minilite 15x7 inch in Anthracite
Tyres
205/60R15 Toyo; Saab compact spare
Body
Rubber-bumper to chrome-bumper conversion, Sebring fender flare kit, ST front spoiler, functioning hood scoop, header cutouts, custom mesh grille
Interior
Early 1970s dash, custom white-face gauges, Grant steering wheel, Mazda Miata seats, AM/FM with CD and hidden antenna, carpeted trunk

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

Fuel & Ignition 8

  • Edelbrock Performer intake manifoldEdelbrock

    Fitted for the V8 conversion induction system

    In the shops
    Intake Manifold ↗Moss Motors – Triumph TR6/TR250· $305.25 USD
    Intake Manifold Adaptor ↗Moss Motors – Triumph TR6/TR250· $0.00 USD
    Intake Manifold to Head Gasket ↗Moss Motors – Triumph TR6/TR250· $6.40 USD
  • Edelbrock 500cfm carburetorEdelbrock

    Re-jetted with new needles and jets as stock setup ran too rich

  • K&N air filter with Extreme topK&N

    Paired with a 1.5 inch drop-base to clear the hood scoop area

  • Buick distributor

    Used for ignition on the V8 conversion

  • Pertronix ignition modulePertronix

    Installed in the distributor for electronic ignition

    In the shops
    Pertronix Ignition Coil ↗Moss Motors – Triumph TR6/TR250· $68.50 USD
    Pertronix Ignition Coil, ballasted ↗Moss Europe (UK)· £112.50 GBP
    Pertronix Ignition Coil, non-ballasted ↗Moss Europe (UK)· £112.50 GBP
  • MSD ignitor box and tachometer adapterMSD

    Used to run ignition and tachometer signal

    In the shops
    Reduction Box, tachometer ↗Moss Europe (UK)· £104.50 GBP
  • RV8-style headers

    Ceramic-coated, routed through the inner fenders with reinforced cutouts

  • Stainless steel 2.5 inch exhaust system

    Single-pipe system fitted for the V8

Cooling 4

Gearbox & Drivetrain 2

Suspension & Steering 5

  • Lowered front springs

    Fitted to the stock rubber-bumper front suspension to lower ride height

    In the shops
    Lowered Front Spring Set ↗Moss Motors – Triumph TR6/TR250· $159.99 USD
    1" Lowered Spring Set ↗Moss Motors – Triumph TR6/TR250· $147.50 USD
    Spring coil lowered MGB ↗Motaclan Limited· £43.44 GBP
  • V8 bushings

    Fitted to the front suspension for the conversion

  • New lever dampers (front)

    Replaced on the front suspension

  • Reverse-loop rear springs (MGS 40721)

    Used as an alternative to lowering blocks at the rear

  • Grant steering wheelGrant

    Fitted in the interior conversion

Brakes 3

Wheels & Tyres 3

Body & Trim 4

Interior 3

Electrical 1

  • AM/FM with CD player and hidden antenna

    Installed in the interior with a concealed antenna

Photos

20 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.

Simon Austin's 1977 MGBPhoto: BritishV8: the site for enthusiasts of modified British sports cars
1977 MGB with 3.5L Rover SD1 V8Photo: BritishV8: the site for enthusiasts of modified British sports cars
1.5 inch drop-base air cleaner, K&N filter, and K&N Extreme topPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Ceramic-coated RV8-style through-the-inner-fender headersPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Ceramic-coated RV8-style headersPhoto: BritishV8: the site for enthusiasts of modified British sports cars
transmission tunnel modification for LT77 transmissionPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Rover LT77 transmission clearancePhoto: BritishV8: the site for enthusiasts of modified British sports cars
making room for the Rover SD1 transmissionPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Grant steering wheelPhoto: BritishV8: the site for enthusiasts of modified British sports cars
One-of-a-kind custom white-face MGB gauges.Photo: BritishV8: the site for enthusiasts of modified British sports cars
Mazda Miata seats in an MGBPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Original MGB grille-surround (re-chromed), owner-installed mesh insertPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Lund hood scoop and K&N air filter systemPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Lund hood scoop from belowPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Authentic Minilite 8-spoke wheelsPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Sebring style fender flaresPhoto: BritishV8: the site for enthusiasts of modified British sports cars
Reverse-loop springs, part number MGS 40721Photo: BritishV8: the site for enthusiasts of modified British sports cars
Reverse-loop springs, part number MGS 40721Photo: BritishV8: the site for enthusiasts of modified British sports cars
Saab compact spare tire.Photo: BritishV8: the site for enthusiasts of modified British sports cars
Donate Now!Photo: BritishV8: the site for enthusiasts of modified British sports cars

How it was done

Starting with a clean shell

Simon bought a late-model California MGB shell in 2000 with no engine, gearbox or interior, but crucially no rust. He chose a late shell specifically because it would be easier to convert from rubber bumper to chrome bumper than to modify an early car.

Sourcing the V8 drivetrain

A few months later he acquired a 1980 Rover SD1 3.5 and its five-speed gearbox. The engine was rebuilt to stock specification and the gearbox only needed an oil pump change before being paired with the Edelbrock intake and carb setup.

Fitting the induction system

Finding room for the air filter under the stock hood was difficult. After trial and error with needles and jets to pass local emissions testing, he fitted a 1.5 inch drop-base with a K&N filter and Extreme top, leaving about 1/8 inch of clearance.

Converting to chrome bumper

The rubber-bumper to chrome-bumper conversion kept original chrome-bumper brackets at the rear, attached to the frame rails, while the front rubber-bumper brackets were removed and replaced with longer L-brackets using the factory captive nuts.

Bodywork and the Sebring kit

Fitting the Sebring fiberglass fender flare kit took considerable work; Simon found the front fenders fit poorly and suggests others cut off just the flares and bond them to steel fenders instead, though the rear quarter flares fit better.

Hood scoop and cooling

A Lund ABS hood scoop was modified with a Dremel to open functional inlets, then fitted by his body shop, who plasma-cut the hood and bonded the scoop from below. It clears the air filter assembly and feeds cool air into the bay.

Interior and finishing touches

Mazda Miata seats were reupholstered for comfort and style, a Grant steering wheel was added, and a friend created custom decal white-face gauges by reversing scanned dial images. The grille surround was re-chromed with a hardware-store mesh insert.

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 ↗

Worth knowing

  • Starting from a rust-free late shell made the chrome-bumper conversion much easier than modifying an early car.
  • Fitting an air filter under the stock hood took persistent trial and error even with a drop-base and low-profile filter.
  • The Sebring fender flare kit's front fenders fit poorly; cutting off just the flares and bonding them to steel fenders works better.
  • Drilling extra lowering holes above the factory front mount holes dropped the ride height too far, so the original holes were best.
  • A small Edelbrock carb still needs careful needle and jet selection to meet local emissions testing.

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