Because the Rover V8 is not the same as the popular Buick V6 or the Olds 455. It was derived from the Buick 215 which was discontinued by Buick in 1963. The iron Buick small block took over after that and ran through 1980. So the great majority of Buick small blocks out there are those later model iron jobs.

The Olds 215 was based on the Buick 215. It was arguably a little better or at least stronger than the Buick version because Olds made a few changes with the intention of producing a turbo-charged version, which they did and called the Turbo-Jetfire. It went into one of the first turbo cars offered to the public, the '62 F85/Cutlass (some say it was the very first turbo car ever, others argue the Corvair beat it to be the first by two weeks). It was also discontinued in 1963. After that, Gen 2 Olds engines took over and that is what we mostly have today.

Ultimately the reason Rover could buy the Buick 215 is because GM was done with it. They were going another direction, notably with less problematic iron blocks. According to the literature, the chief reason GM dumped the 215 was because of the high cost of the Aluminum blocks due to the high scrap rate. They had casting problems with porosity and what made it especially costly was that they could sometimes not determine the need to scrap a block until it was as much as 90% complete. That ate up a lot of machine time making paper weights, which made the cost of a successfully finished block much higher than expected. What made them more viable later on was improvements in casting-sealing technology. In the beginning, they were way ahead of their time. Although I understand they were not alone at all. Aluminum had certainly been used earlier in aircraft engines, but in the late 50's Alcoa has started a big push with auto makers for Aluminum use and by the early 60's there were a number of new aluminum engines like the AMC straight six. The Buick was the first V8. Even toward the end (the 90's and up to 2006), they still suffered a bit having been an early adopter in a time when some of the competition was using designs that were birthed out of mature technology.

So essentially the reason we don't use Buick and Olds 215 engines is because they are far more rare than Rover V8's, which are quite plentiful.

If you're just asking why we don't use an Olds 455 or any of the newer engines, the reason is simply because they don't fit. If you found one that physically fit into the engine bay, you could adapt the bellhousing to the tranny (the ZF automatic is not an uncommon tranny at all), and then you just need to make engine management work. If you just had a distributor and a carburetor, you'd be set. But if you want electronic ignition and fuel injection, the adaptation gets trickier. For most people, the Land Rover is not worth it. If you're going to build such a custom project, why go farther with your own chassis and suspension and body or at least do the swap on something that doesn't leave so much to be desired.

 

put a BMW motor in it. guy on pirate started with a M52 straight 6, now is in the process of dropping the M70 V12 in it. bolts right up to the ZF trans. this is in a RRC but its the same thing.

 

That's eye opening. I would have never thought to use an in line six in the Rover's short ish engine bay. Very cool. I went and read his "build' thread and apparently he didn't finish w it. No ps would be my biggest problem.

 

I read all those from the BMW engines (which I have experience with and love them), to Jaguar 3.6 I6, Volvo I4 diesels, and yes the BMW V12. All bolt up to the HP22, but all have problems that could prove to be a pain. From oil pan sumps on the wrong side of the engine, to ECU configuration. It isn't as easy as you'd hope. I really gave thought to the older BMW I6 (M50B35) which is 3.5L and is easily turbocharged with no mods. I've had one of these in a 535i, and they are bulletproof. A small turbo that spools up instantly would provide instant torque (like 300+ from 1500rpm up), and be perfect for a Rover. However, the sump is facing the wrong way (as is the V12's). The Volvo 2.4L diesel would be cool, but making enough power on those is tough to do, plus everything involved with swapping from gas to diesel. At the end, for my time and budget, a stroked 4.0 to 4.6 makes the most sense for me. However, a turbo I6 or V12 would be awesome given the time and $$$ to do it right.

 

My son has a 94 BMW 530i (E34) with the M60 3.0L V8 32V and it out produces our junk by almost 40 ponies and it has the ZF 5 speed auto. His car scares me, it's so sure footed on snow with the posi that it is perfectly manageable fishtailing back and forth at 60mph.

I'm looking for a 540i right now.... I'm surprised nobody's mentioned these as a perfect transplant before now.

 

So, not to belabor the point, but you're saying that a small block engine out of a 1990 (let's say) LeSabre or Delta 88 with throttle-body fuel injection would fit right in place of the L/R 4.0? I wouldn't necessarily do it either but I can see where it could be a very cheap swap if a guy bought a cheap carbed RRC that had a blown motor and a Delta 88 sitting at the neighbors house kind of thing. I was just wondering if the late model buick small block would technically mate to the tranny and everything fit right up. (don't worry, my disco's motor is running nice..)



Thanks.

 

I thought of that one too. Cool engine, and a kind of a BMW rarity. It being rare and only 3.0L (I need down low torque) never made me seriously consider it though. It did come with the HP22 in the 530i too (I think). 215ft. lbs ain't cutting it though, so forced induction would be the only answer, which is why I went with a turbo B35 (more parts availability reliability, and linear torque). I think that would be a cool build for someone willing to do it.

 

It is rare and sat in a garage not started for eight years.

 

My Ol' Ladies 2010 X3 has a inline six 3.0i and it gets up and moving. Good motors and very efficient.

 

When the motor went in my 110 I gave serious consideration to the Jag 3.6, it is a fantastic motor and the wonderful noise it makes at WOT is addictive. I drove a 89 Jag XJ6 for a few years and loved the car. The only reason I didn't do it was I found a good 3.9 RV8 and hadn't found a good Jag motor. Hell I'd love to stuff the Jag 3.6 into my MGB, I bet it would be a blast.