We’ll start with the specifications:
Overall length - 690 mm
Overall width - 580 mm
Overall height - 495 mm
V-type 12 cylinder engine - 75* angle
Total displacement - 3,493 cc
Maximum output - 646 PS @ 12,000 RPM (early design) / 765 PS @ 13,500 RPM (late design)
Maximum torque - 41.0 kg/m @ 10,000 RPM (early design) / 42.5 kg/m @ 11,500 RPM (late design)
Bore - 85 mm
Stroke - 51.3 mm
Compression ratio - 13.0:1
Weight - 158 kg
I think that mostly speaks for itself! 765 hp at 13,500 RPM - from Isuzu! So, why did this motor even exist?
There’s actually some decent information on the Japanese Wikipedia page, which I’ll try to sum up here, right quick.
At the time (the late 80s/early 90s) Isuzu was mostly famous for building diesel engines. Interestingly, they’re still really famous for building stellar diesels, but back then they wanted to see just how far they could push themselves in the world of gasoline engines. So, they wanted to build an engine that could be capable of competing in Formula 1 and Group C. Interestingly, Nissan also had a 3.5 liter, twin cam V12 engine called the VRT35 installed in their P35 group C racing car. The Nissan engine made 630 hp @ 11,600 RPM, so the Isuzu engine would have been a very strong competitor.
As we all know from the “Handling by Lotus” badges that many Isuzus came with, Isuzu and Lotus had a bit of a relationship in the early 90s (largely due to their both being tied very closely to GM). As such, the engine was installed into the Lotus 102B, creating the 102C. The car was largely the same, but in order to fit the V12 into a car designed around a V8, some modifications had to be made. Namely, the engine mounts, the bellhousing and the engine cowling were all modified. On top of that a larger radiator was installed.
The V12 equipped car underwent fairly heavy testing at the Lotus test course, and then at Silverstone circuit. At Silverstone, it set a fastest lap of 1:30, approximately 6 seconds slower than what Ayrton Senna managed in the Mclaren Honda at the time. Peter Collins, the former racing team manager for Lotus, said “This is the first time I’ve seen a racing engine start on the first try.” Do keep in mind that that quote is going from the original English Mr. Collins said it in, into Japanese and then back to English, so it may not be exactly what was stated.
After the test, Isuzu judged that they were indeed capable of creating a wicked engine and ceased production of the motor after just seven examples. This engine was quite literally an engineering exercise – a “let’s do it, just to see if we can.” Interestingly, the engine did get installed in one more vehicle: the Isuzu Como concept. This was a mid-engined monster that really didn’t fall into any category.
Here’s a translation from the Isuzu website:
“It’s not a passenger vehicle nor a recreational vehicle. Designed to whisk passengers and a large amount of cargo from the city to a resort in comfort and at high speeds, it’s an all new genre: ‘Grand Sports Utility’.” The website goes on to further explain that by placing the engine in the middle, they have ensured enough space for luggage as well as passengers, creating a super sports pickup.
Aside from the absolutely mind blowing looks, it’s quite amazing when you realize that they even designed it to fit four full-size adults. Isuzu claims this is due to the mid-engine placement and the long wheelbase. Isuzu is no stranger to awe-inspiring designs (I’m looking at you, 4200R), but this one takes the cake in my book! The Como name was actually used on a production vehicle, however, it was just a badge engineered Nissan Caravan. Oh how I wish we could have gotten a mid-engine super sports pickup truck!