The Cooling System
On all MGBs fitted with an engine-driven cooling fan, the radiator is not large enough to cool the V8, The larger MGB GT V8 radiator should be used, mounted towards the front of the engine bay.
Unfortunately there is no room for an engine-drive. fan, so twin electric fans are fitted under the slam panel. Be sure to check the clearance between the bonnet release lever, in both the open and closed positions, and the left hand fan blade as it is very close. A Kenlowe thermostatic control is used to switch the fans (however it is best to wire the fan motors through a relay as they do consume a large current), some converters have wired in a manual over-ride switch. A guard can be mounted over the blades.
The V8 radiator requires a separate header tank, which is positioned on the left hand inner wing, adjacent to the distributor.
On late model MGBS, with an electric cooling fan, the core in the original radiator is the same as the V8, but the top and bottom tanks will require reversing and modification. The late model MGB is already fitted with a header tank.
On most production Rovers the radiator is normally mounted higher than the engine and the top hose is at an angle. In the MG the radiator is on the same level, so problems may occur with air locks. If this is the case a special thermostat housing is available.
A rear water outlet should be fabricated to enable the I800 B heater valve to be used.
The Wheels and Tyres
The MGB has been fitted with 14" diameter wheels. There have been three types: 4 J bolt-on steel wheels, 4 1/2 J wire wheels 5 J Rostyle wheels. The standard tyre fitted to the 1800 was 155 or 165 SR 14. With the increase in power and possibly in top speed there will be a greater strain on the tyres. If you have changed the axle ratio you will nave to fit HR rated tyres to comply with insurance regulations.
The works V8 was fitted with 5 J Dunlop wheels and 175 HR 14 tyres, This size tyre is the largest you can ft to the wire or Rostyle wheel, although some owners have increased to 185.
The MGRV8 is fitted with 6J alloy wheels with 205/65 VR 15 but do not forget the wheel arches have been modified.
Once the tyre size is increased beyond 175, problems may occur with the wheel arch to tyre clearance. If you decide to change your rims, the choices of profiles, rim sizes etc. are very extensive. Smaller track rod ends are available if the clearance on the inside of the rim is a problem. I5" diameter wheels are another option.
The standard B size wheels have been used in the past but these will obviously have to be in good condition. If the car is driven hard it is well worth considering the wider competition wire wheels with more spokes.
V8 Conversion Project
Overview of Project
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