Though the J2 was the most famous of all Allards by far, only 90 were built. Untangling the web of which cars had which engines is nearly impossible. Generally, U.S.-bound cars were shipped across the ocean with no engine, and one was fitted to customer specification before, or often after, delivery. In any case, the hot engines, the ones that made the J2's reputation, were the Cadillac and Chrysler Hemi, each displacing 331 c.i.d. From the factory, the Cadillac was rated 160 bhp at 3800 rpm and 312 lb-ft at 1800 rpm, while the hemi-head Chrysler was said to be good for 180 bhp at 4000 rpm and 312 lb-ft at 2000 rpm. Both were easily improved. Interestingly, the solid Ford rear axle used on other Allards had a track of 56 in., while the De Dion rear suspension of the J2 had a track of only 52 in. The result was that J2s often appeared to be "crabbing" down the road, when in fact they were running straight. The J2 was the ultimate British hot rod. Because its components were built for much heavier cars, they seldom broke, and for a few glorious years before the rest of Europe caught up, it was very difficult to beat.