Ford Capri Turbo May

Mike May

Mike May (Europe's first Formula Junior champion and a winning Spyder RS racer) was a German-domiciled Swiss turbo specialist - and his V6 2.6 turbo kit was keyed to a specific engine/gearing combination, as designed on his own engine dyno. These were then sold as after-sales kits (which helped beat American emissions laws) through selected Ford dealers.

Even Ford of Cologne went along with this and their largest garage in Germany had been fitting smaller V6 Fords since 1970. The short, stiff crank made the 2.6 litre an ideal engine for turbo-charging. There were three figures that told you why the Turbo May Ford Capri (Cologne 2600 V6) was a different ball-game entirely. One was the maximum horsepower, lifted from 125 DIN to 208. The second was a full-bodied 192 lb/ft of torque at 5000 rpm. But the figure most published by auto journals of the time was 12 seconds - that being for the 60 to 100 mph sprint using top gear only.

Jekyll and Hyde

The Turbo May Capri was a bit of a Jekyll and Hyde proposition. Around town, you could drive it sparingly and it would behave just as any 3 litre European car from the time. But sink the foot, and the power on tap was more akin to that derived by a big-bore American V8. For the time, the power and torque curves were simply amazing. It was easy to achieve acceleration figures like 15.6 seconds for the standing quarter mile, and this could be improved on with practice. Compared to the works injected Capri RS, the Turbo May was faster and nearly half the price. A real bang-for-your-buck proposition.

In fact, the May was so good they left the factory with an electronic rev limiter aboard to avoid engine damage, and primarily because it was required by the German licensing authorities in deference to the only slightly modified 2600 GT XLR Capri chassis and brakes. If you disconnected the rev-limiter, you could really push some boundaries. The normal red-line was 5800 and for most driving conditions you never needed to exceed this. But some road testers, in the interests of good journalism, did push the boundaries. These brave few found the practical limit for full thrills was more like 6500.

Removing the Rev-Limiter

Even at the nominal rev-limited redline you were doing 35-60-93-120, finally winding out to a top speed turned of 128 mph. These figures were nearly matched by the RS, but again that car cost a lot more, and in the process of getting near the performance the fuel consumption would suffer dramatically. The normally aspirated RS would admittedly accelerate hard, but the second half of the acceleration curve was slower than the first. And that's where the turbo came into its own, with a willingness to climb the tachometer like a demented monkey (no offence to monkey's, of course).

A turbocharged Capri went up to 100 in 21.5 s and did it by gaining speed nearly as rapidly above 80 as it did below that point. As an example, 60 mph in top gear with a 2.6 Capri required 3000 rpm. And that was precisely the point where the turbocharger came in when you need to overtake suddenly. For a given speed, say 70 miles per hour, the consumption in the Turbo May Capri was less than 0.5 mpg above that for a carburetted 2.6 Ford V6. It put in consumptions figures just a touch under 19 mpg.

We are not sure that anyone bothered, but it was possible to unbolt the turbocharger and switch it to another V6 unit as required - perhaps when selling or trading up. That was because you didn't need to touch anything else. Bearings, gaskets, even the carburettor were stock. Only the plugs needed to be changed, for colder Champion N2G items. The two exhaust manifolds had to be swapped of course, for May units with the turbocharger mounted directly on the right manifold and a pipe from the left bank crossing under the engine to the blower. The blower itself, its trunking, air filter and a welded-up can atop the carburettor (May used the original air cleaner can) completed the kit. The installation was particularly neat under that Capri bonnet.

The Patented Control Unit

The heart of May's blower success was his patented control unit which took care of atmospheric twitches, temperature, flow and revs, thereby surmounting the problems which turned GM off with the Corvair and Olds. It meant that, on the road, there was not any surging on acceleration, there were no flat spots from 600 revs to 6000 and no loading up on over-run.

But some road testers, particularly those that spent some time with the car, did discover a small problem - heat build-up. To keep modifications to a minimum, May used a stock Capri cooler. For cold starts you simply waited a moment for the pump to fill the carb (a la injection) and turned the key. It started immediately every time. When the engine was fully warm and you had to start and stop it several times it took some cranking of the starter with right foot well away from the accelerator before it would fire. Initial idle was about 1250, but once the engine warmed up it would tick over at 600 even after long, hard runs.

Apart from the engine, the Turbo May was virtually standard and that meant no modification to the Capri chassis. This is where the RS perhaps earned its keep. Ford lowered the RS with special front links and single-leaf rear springs. That meant that the RS would bottom on pretty much anything, but it also meant the car was capable of handling the extra power. The Turbo May kit did not include suspension change, but for his own car it is telling that May compromised. He used the single-leaf RS back end but left the front nearly standard Capri, which gave a drag strip launch attitude when you scan the profile. It also let the car wander at higher speeds, so that driving could be an adventure.

Inside the car was almost standard - but that was not such a bad thing as the Capri was a great car to be inside. Ford were usually leaders in instrumentation and seating, and the Capri was no exception. Bucket seats were a good idea if you added the Turbo May, given the lateral g forces possible. All this and the cost was only a few dollars over $A700, a fair deal for turning your Ford (any 2.6-litre V6, sedan or Capri) into a fire-breathing beast.