Is the Jaguar F-Type’s old V6 really just a V8 with two cylinders blanked?

We’re huge fans of the AJ133 V8 plumbed into the sleek nose of the Jaguar F-Type P450 RWD. It’s loud, punchy and extremely charismatic. Of course, it’s not short of its quirks, most notably around timing chain tensioners and plastic parts in the coolant system and inlet manifolds, but it’s nevertheless one heck of an event. Every single time.

One story keeps cropping up about the AJ133 engine, however, and it sounds so implausible that it almost has an element of bar-room urban myth about it. It’s the claim that the AJ126 V6 that Jaguar also offered was this same engine just with a pair of cylinders blanked off. So is it true?

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Supercharged V6

Well, pretty much. There are some materials differences between the two engines. The AJ126 takes the AJ133 block and does indeed blank off the rearmost pair of cylinder bores. There’s more to it than that, however, as Jaguar also reduced the bore of the remaining six cylinders from 92 to 84.5mm and the stroke from 93 to 89mm, reducing swept capacity from 5000 to 2995cc.

While the exterior dimensions of the block are the same as the V8, there’s a shorter cylinder head. Still, the six-pot is probably carrying around 20kg of extra – and redundant – heft from the bigger block, crank and oil pan.

Also because the AJ133 features a 90-degree design rather than the usual V6 60-degree preferred for NVH reasons. A split-pin crankshaft means that a cylinder fires every 120 degrees of crank rotation and a contra-rotating balancer spins at the end of the crankshaft.

So, yes, it’s kind of true, although Jaguar did more than just bog up a pair of cylinders. With the facelift of the latest F-Type, Jaguar’s waved goodbye to the AJ126 six-pot, on these shores at least. What better reason do you need to look at the full monty V8?

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