RND 800 BHP 7.2 litre Speed 12 roject breaks cover at 2025 UK Classic Motor Show
On display upon the TVR Car Club stand at the NEC Classic Motor Show in November 2025, was the first the general public has had a chance to view current progress on RND Engineering's Speed 12 engine project. The unit is based upon the proven Jaguar V12 block, whose bore spacing was found to be virtually identical to that of the DOHC cylinder heads used on the TVR Speed 6 models. 800 BHP is projected from the 7.2 litre displacement power plant, with 600 ft lbs of torque at 6,500 rpm.
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IN-CAR DRIVERTRAIN SPECIFICATION RND Speed 12 7.2 LITRE V12 ENGINE | |
| Bore - | 3.84 Inches or 97.5mm |
| Stroke - | 3.150 inches or 80 mm |
| Compression ratio - | 12.1 to 1 |
| Throttle bodies - | Jenvey 50 mm |
| Ignition - | E.M.S 3 map wasted spark semi-sequential injection system |
| Rotating Assembly - | Forged Pistons, H Beam Rods with 7/16 th ARP 2000 lbs ft tensile strength rod bolts, steel crankshaft. |
| Block - | ll Aluminium, with 6 bolts main Cap |
| Cylinder Heads - | TVR 4 Valve Per Cylinder, quad camshafts, duplex timing chains, one to each bank |
| Clutch - | 10 Inch / 234mm twin plate so as to support 1000 BHP + |
| Transmission - | Quaife 6-speed sequential gearbox |
| Differential - | 9 Inch / 228.6mm independent LSD 3.09 Ratio > |
| Power Output - | projected, Sim 5 dyno power simulation program |
| Peak BHP = | 800 @ 7500 rpm |
| Peak Torque = | 600 Ft Lbs @ 6500 rpm |
Projected power/torque curves for RND Speed 12 engine. Source: DynoSim5 Version 5.03.1011
The Speed 12 showcases the automotive design skills of RND Engineering and CNC specialists John Finch Engineering, leading Al Melling, the originator of the TVR Speed 6 as well as other notable road and race engines, to comment, 'The engine is a study in maintaining the typical V12 appearance and shows that the small volume engine experts are (still) out there'.
For Melling, 'My experience with the Jaguar cylinder block brings back memories of the sadly shelved TWR V12 for the Jaguar 220 car, and the TWR engines. This cylinder block was designed many years ago and has gone through many modifications, for race use and now in this wonderful guise, using my designed cylinder heads'.
Melling is in a unique position to comment, as his career in the motor industry has been peppered with an involvement in both multi-valves and Vee engines. His work with TWR led to the Jaguar team winning Le Mans for several years in a row, and under the banner of his own consultancy, he developed both the 200 mph plus Hellcat and the later Wildcat sports cars. And in the bike world, his name will always be linked to that of the Norton Nemisis V8, whose back story is included along with many other intrigueing insights, in a recent autobiography, 'Under the Cam Covers'.
Al Melling - biography, 'Under The Cam Covers' ISBN 978-1-3999 8157-6
Much more than a mere 'tribute' engine, the RND Speed 12 project was developed around power with reliability. Dave Davies of RND Engineering, is no stranger to the TVR legend, admitting to - like a dog with a bone - 'Having spent four months studying the original Melling design blueprints for the Speed 6', when considering how best to extend overhaul intervals and improve performance of the road cars.
Workshop view of semi-assembled long block for RND Speed 12
Whilst Melling did some work for TVR om both a V12 and a V10, TVR went their own way, and built at least two V12 prototypes of their own design themselves, one of which was installed in a Cerbera. But the engines suffered from reliability problems, and it is said that for a road car, they were deemed to be 'too powerful'.
The RND interpretation also draws upon Davies' long experience in modifying high-power, high torque American V8 blocks, and features 6 bolt main bearing caps, with steel crankshaft, 'H' beam rods and forged pistons. It is also unusual in this day and age, for delivering the power that it does without the benefit of turbo or super charging.
Bore and stroke are 'over-square' at 97.5 mm x 80 mm respectively, yielding rapid throttle response from this 12.1 : 1 compression ratio engine. Matched to 50 mm Jenvy injection throttle bodies feeding fuel and air through the 24 valve heads on each bank, the RND TVR Speed 12 is expected to produce 800 BHP at 7,500 rpm, and should reach a maximum torque of 600 lbs ft only 1,000 rpm below its actual power peak.
What is also interesting about this 'bespoke' variation upon the V12 theme, is the way great care has been taken to 'productionise' the engine. Though still largely hand built, and demanding a high degree of traditional fitting skills in balancing, and in the careful assembly of the many rotating assemblies, extensive use has been made of CNC and CAM technologies. This means that components which would formerly have been specially cast and then conventionally machined, can now be made from billet materials. A case in point being the front timing chain enclosure, which carries the duplex chain drive from crank nose to the two camshaft sprockets in each cylinder head.
Not by any means a V12 'for the masses', but certainly bringing an engine of this power and potential within the reach of perhaps more people than would formerly have been the case.