Stage 1 V8

Hi, I don't have a Stage 1 V8 Series 3 Landrover although I drove a nearly new one in 1980 from Ely to Watford. I have a Triumph Spitfire with an SD1 3.5 V8 which would be MOT exempt if it could make so little power! What was done to the Stage 1 V8 to get it down to 91 bhp?

http://www.glencoyne.co.uk/stage1/v8improv.htm

Why would your Triumph Spitfire be MOT exempt?

Presuming that you are using a concurrent SD1 or SE engine, then: compression ratio, jets, needles, distributor advance curve and restrictors in the carbs. Otherwise the camshaft profile as well.

Geoff wrote:http://www.glencoyne.co.uk/stage1/v8improv.htm

Why would your Triumph Spitfire be MOT exempt?

Under the VHI Roadworthiness Testing Exemption Legislation, the Draft Guidelines on the Definition of 'Substantially Changed' allows for vehicles which meet the 8-point rule and have no more than a 15% increase in power to weight ratio to qualify for MOT exemption if they are over 40years old (coming into force next May), unless kit cars or rebodied chassis with totally changed appearance. As my Spitfire has gained weight from the engine/gearbox swap it can have about 30% more power. Just curious as to what I'd need to do to halve the output! It has the Holley 390 on Offenhauser manifold at present, which is rather too torquey for the good health of the differential and driveshafts. I didn't build it!

If you could live with the bonnet bulge, the smartest move would be to change to EFI with two programmes. One for 'economy', essentially minimal power and the other being the opposite. The slightly later Range-Rover plenum being highly effective in standard form. The Rover Se version being capable but not as good. A modification rarely performed but extremely possible with aftermarket computers for the past twenty years.