Taper Throttles kit are made up from 4 single bodies (on a 4 cylinder engine) which is 66mm long tapering from a 48mm diameter hole at the ram pipe end down to 42.7mms at the manifold face, with a 45mm butterfly in the middle.

The main advantages of using a tapered singled body over parallel bodies & slides that we have found in tests are:-

1.        Being individually adjustable they can be perfectly set-up.

2.        We have found that the use of a taper that continues the shape of the ram pipe right through the throttle & manifold up to the valve, has improved torque through almost the entire power band

3.        Also we have found that the use of a 45mm butterfly in junction with a taper has improved throttle response. We carried out tests quite a few years ago comparing a taper throttle body with a slide throttle; both being of a similar size, as it is had been suggested to us that an intake system such as slide or barrel throttle systems, would surely produce more power because there is no butterfly restricting the port. The back-to-back test showed virtually no difference in peak power at all, but the throttle response on the taper body system was significantly better than the slide system. We also have found more recently in tests the similar poor throttle response with barrel throttles.

4.        The peak BHP that we have seen from the tapers (with 45mm butterfly’s) is better than we have achieved in similar tests using 48mm parallel bodies or a slide throttle assembly.

The injectors are the same as the MT system and we use the same ECU but that is where the similarity ends. With a very different programme using this basic kit on a standard 2.0 litre 16v XE engine an output of 208 BHP is achieved. Needless to say we used one of our exhaust manifolds, on a closed cell Dynamometer. It cannot be stressed too highly that these kits will only yield their true potential when used in conjunction with our exhaust manifold or one made to our design and a suitable exhaust system.

The same high specification of loom used which is available off the shelf in 3 versions, rear wheel drive, front wheel drive and mid engine versions. These have been specifically designed to be as neat as possible and to cover as many applications. These wiring looms are kept on the shelf with a selection of coil adapters which will allow you to fit to a range of ignition systems e.g. engines with distributors, engines with distributorless coils (Bosch 3 pin connector type as fitted to the LN engines), or by using our coil COIL-4. Although the kits do allow you to use the standard distributor/coil amplifier set up, it is not recommended because even if you have these parts, the standard cap & rotor reduce in efficiency as they wear & cost over £60.00 to replace each time. The distributorless coil has no moving parts so it can maintain a perfect spark & we have never seen one wear out yet, making the distributor/coil amplifier set up a false economy.

Where space permits this is unquestionably the way to go; smooth power application, high torque and wide power band, this set up has it all. It almost behaves like a standard production car. Starting is simple and the air temperature sensor & Lambda control will take care of the warm up. Once it has been set up correctly, apart from the occasional set-up to adjust out small wear variants the engine will not need re-setting at all throughout the season. It is extremely reliable and forms the basis of all our winning engine/car/driver combinations. It is also the same basic kit that OPEL have been homologated with the FIA and SBD for the Astra Mk III kit car for rallying.

So it is with considerable 'track record' and proven reliability that this style of kit is offered. Certainly all those who have purchased it are extremely complimentary about it and the reports are continually coming in with very positive results.