Brad Chapman's 1975 MGB GT with Rover 3.5L V8
as published in BritishV8 Magazine, Volume XVII Issue 1, July 2009
Owner: Brad Chapman
BritishV8 UserID: evoconvert
City: Bicton, Western Australia
Model: 1975 MGB GT
Engine: Rover 3.5L V8
Conversion by: Owner
| Engine: | Rover 3.5L engine. Holley 600cfm with vacuum secondaries on an Offenhauser "360"
(part number 5165) single-plane intake manifold. Pertronix Ignitor ignition module
mounted inside the dizzy in lieu of breaker points.
Rebuilt SD1 starter motor. Pre-facelift P6 alternator bracket. |
| Cooling: | modified stock MGB (four cylinder) radiator with relocated ports. |
| Exhaust: | custom headers (purchased "used" from a racer.) |
| Transmission: | Toyota Supra alloy case 5-speed manual transmission with Dellow bellhousing.
Dellow clutch kit including transmission mounts, slave cylinder, throw-out fork
and bearing, etc. |
| Front Susp.: | stock MGB. |
| Rear Susp.: | stock MGB. |
| Brakes: | stock, except for MGB GT V8 front calipers. |
| Wheels/Tires: | Minator 15x6 8-spoke alloy wheels. |
| Body: | Sebring front and rear valances. (The heavy rubber bumpers have been removed,
and a 1974-spec grille has been installed.) |
| Interior: | stock MGB. |
| Weight: | 1020kg (2248Lbs). |
| Completed: | February 2009. |
| Comments: | Where to start! I think the main areas of concern I had were the engine
location and the selection of which gearbox to use. I purchased the engine
mounts from the MGOC website. In hindsight, I believe I could've placed the
motor slightly further back (e.g. maybe an inch or so.) However, the height
is good and I have enough clearance to remove the sump pan with out lifting
the engine. I decided to use a Toyota Supra gearbox. In Australia they're
readily available with four different length casings (18, 19, 20, and 21 inch
long respectively). I think the longest version is the most appropriate. I
found that it located the gearstick very near the MGB's original location.
The box I used is referred to as a "w55" box and has very similar gear ratios
to the MG RV8 model. These boxes are good for about 500hp, so they're
virtually break proof. The Dellow bellhousing was a easy install. It clears
the tunnel by about 10-12mm either side, so I did not have to modify the
tunnel at all. At the time of writing, I have not upgraded the
differential yet but I intend to do that soon. (I'd like a limited slip
differential.) |
Holley 600 (vacuum secondaries) on Offenhauser "360" single-plane intake manifold.
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How It Was Done
Custom four-into-one, block-hugger headers.
Toyota Supra W55 5-speed gearbox.
Dellow bellhousing.
Installation of a Sebring front valance.
Installation of a 1974 MGB grille.
The Completed Conversion
