Originally Posted by Shraka
The overall weight isn't a problem. The problem is the length. A longer engine means you have to either have a really long bonnet, or put more of the weight over the front of the front wheels, which makes the balance worse. You always want your engine as close to the center of your car as possible.
Another reason they are not being used as much anymore is because it is harder to make them meet pedestrian crash regs (due to the long, tall engine being closer to the front being more likely to cause injury).
The final reason they are not used so much anymore is because you can't easily make them into a FWD application. A lot of sports engines share a heritage with a consumer engine, and if you can't make it front wheel drive nobody will buy your car (with a few exceptions). Not to mention if you're already designing V6s, you already know the pitfalls of those engines, and are more likely to 'stick with what you know' and not start from scratch on an inline 6 sports engine.
As for Inline 6s being 'old tech', that's not true. They're a layout, not a technology. You can update a layout with new technology.
There are a few more examples than you mentioned too! Just some off the top of my head:
- Nissan RB20, RB25 and RB26 engines, the RB26 being included in the Skyline GT-R, one of the leading sports cars from Japan.
- TVR Speed Six engine in the TVR Cerbera, Tamora, T350, Tuscan, Sagaris and Typhon.
- Inline 6s were used in Formula one from 1947 to 1960.
- Ford Australia's DOHC Turbocharged I6
Also, the ones you did mention: The Toyota Supra 2JZ-GTE is considered by many to be the BEST turbo engines ever developed. It's solid, reliable, and can make LOTS of power without exploding (1000+hp models are almost common). And the M3 is the best, longest lived sports coupes ever. The old M3 engine was brilliant. So you can't tell me they don't make good sports applications.
An inline six not used for ease and convenience, not because the engine design is bad.
Good point, it can be used in high performance applications, however you've only named a few, there are far more V6-V12 variations. As you sited earlier, the size of an inline 6, is somewhat of a hinderance. You have to take into account, the more modern TVR's are considered to be large displacement, some of their engines are similar in size to the smaller "large" displacement V8's.
As for the Supra, it has been well documented that the car is reliable, however that has nothing to do with the application, it's much more based on the design of the iron block, the same can be said of the LS1 and the 5.4 in the Ford GT's (which uses an aluminum block, but still has a bottom end capable of accepting over 1000 hp).
I have nothing against inline engines, my mothers SUV has one, and the idle and pick up is quite smooth. I myself drive a blown V8, and couldn't be happier (except at the pumps). I can understand where you're coming from in regards to rednecks who equate the size of their engine, with their cars performance (that bothers me as well), however I'm just as annoyed by guys in FWD 4 cylinder Civics who continously talk about engine technology, without first taking into account, the final output of the engine and automobile (this was not a reference to you).
The Z06, is quite an engine, but it's performance output would likely be lost on all but the sports car fans, because the tuner crowd would continue to preach about V-Tech this and forced induction that (which as I said earlier, my car is FI).
In all honesty, some of my favorite cars are smaller displacement 4-6 cylinders and rotary; S2000, 93-95 RX-7's, Porsche 911's, not to mention the TVR Sagaris (easy favorite outside of the Ford GT and AM Vantage).