new MR2, Lotus?

[rgh0]

I did not say the BDA was not a contributor to the 4AGE design, it was, just as many engines contribute to many engines design as i have tried to highlight. All true great engineering work is evolutionary.

There is no need to denigrate the Toyota engineers as mere copyists just because you think the Ford and Cosworth engineers were the best and the only people in the world who do original work. They were good, but please understand what true engineering is all about and don't denigrate some of the best engineers in world at Toyota. Read Shigeo Shingo and Taiichi Ono, their books are a great source of learning and may be you will get some idea about what real engineering is all about

cheers
Rohan
Yes I have a name

[2cams70]

I have utmost respect for Toyota in the areas of uniformity, conformity, systems and quality. Product innovation is not one of them (generally speaking of course - there are some notable exceptions that I highlighted earlier).

Uniformity and conformity does not foster a creative environment. The two are mutually exclusive.

If you want to read about a Japanese automotive company with a long history of innovation and sucessfull competitive motorsport at the highest level I'd suggest you read the "Power of Dreams" about the history of Honda and it's founder Soichiro Honda.

The main reason why I don't share my name publicly to everyone on this forum is that I actually work in the Automotive Industry and so have a bit more at stake than those that don't. Provided people aren't using anonymity as cover for being abusive they should be respected for that wish. Send me a PM if you want to know who I am. If I feel comfortable I'll be more open.

[vstibbard]

The arguments are simplistic and there are many many more issues in engine design than a journalistic comparison of bore and stroke and port shapes. To say the 4AGE is a simplistic copy of the BDA is a trivial comparison. The 4AGE is a great engine in its own right just as the BDA is a great engine with a long history of engines it was developed from as you have highlight ( and some you have not)

Its like saying the Datsun L16 engine is a simple copy of the Ford bottom end and Mercedes top end as that is some of the sources of their design and why an L16 crank drops into a twin cam with a little machining. The L16 is a great engine in its own right The fact that an L16 crank is as good a the purpose machined racing cranks shows it was not a simplistic copy of the crude value engineered to death Ford cast iron crank.

cheers
Rohan

always happy to discuss engine design

As I understand it the Datsun l16 is a rip off of BMW1600 engine and Reese independent suspension!!!

[rgh0]

The arguments are simplistic and there are many many more issues in engine design than a journalistic comparison of bore and stroke and port shapes. To say the 4AGE is a simplistic copy of the BDA is a trivial comparison. The 4AGE is a great engine in its own right just as the BDA is a great engine with a long history of engines it was developed from as you have highlight ( and some you have not)

Its like saying the Datsun L16 engine is a simple copy of the Ford bottom end and Mercedes top end as that is some of the sources of their design and why an L16 crank drops into a twin cam with a little machining. The L16 is a great engine in its own right The fact that an L16 crank is as good a the purpose machined racing cranks shows it was not a simplistic copy of the crude value engineered to death Ford cast iron crank.

cheers
Rohan

always happy to discuss engine design

As I understand it the Datsun l16 is a rip off of BMW1600 engine and Reese independent suspension!!!

I agree there are many similar features between the BMW 1600 engine and the Datsun L16 engine as well as with the 4 cylinder 1600 cc engines of Ford and Toyota and Mercedes engines of the time. All these designs are evolutionary most have a few innovative features at the detail level but at a macro level they are very similar as they are all driven by the same fundamental requirements and manufacturing technologies used at the time

e.g. There is a lot of similarity between the bottom ends of the various manufacturers 4 cylinder 1600cc motors from people like Datsun, Toyota, Ford, BMW, Mercedes of the time as they are driven by the fundamentals of iron casting technology used, engine packaging requirements and desirable bore / stroke ratio, required bearing diameters and lengths to carry the loads, all of which interact and create a small space to operate in, in terms of design dimension selection. If you go into the next layer of details of material selection for individual components and component detail design and manufacture you start to see more variation.

If you look at the cylinder head designs for single OHC production engines of the era you see a little greater variation driven by variation in the general type layout selection for the valve train and how its cam is driven and port layout etc but the fundamentals of gas flow into and out of an engine again drives a lot of similar outcomes.

Similarity in engine design outcomes does not mean the designs, were specifically copied, it just means that the same fundamentals applied and why reinvent the wheel if the work has already been done.

If you look at the typical 2l 4 cylinder turbo engines of today they are again mainly similar from all manufacturers with the notable exception of Subaru who made a fundamentally different engine packaging choice going to a flat boxer engine layout many years ago and have followed that path for a long time now with the exception of the most recent partnership with Toyota.

cheers
Rohan

[2cams70]

As I understand it the Datsun l16 is a rip off of BMW1600 engine and Reese independent suspension!!!

I agree the Datsun L16 is very similar to a BMW M10 engine. It looks to be a combination of BMW M10 bottom end and Mercedes SOHC top end. Despite the fact that the crankshafts drop into a Ford Kent engine with little modification there's not much else that's similar. The L16 and M10 engines both have main bearing caps recessed into the block. This has the disadvantage of making the engine taller and heavier. It may contribute to block rigidity but probably not a great deal and certainly not as much as modern engines having a very rigid ladder structure for the main bearings. The Datsun engine is way over designed for what it needs to be. The reason why a nodular graphite cast iron crankshaft is a good choice for an engine not required to spin at high RPM's is that it's much lighter than steel and the engine is more responsive as a result. Ford recognized this with the 105E and the original crankshafts were hollow as a result (a revolutionary idea but not durable long term). The beauty of the 105E engine family (that includes derivatives Twin Cam, BDA, etc., etc., etc....long list!) and what went a long way in making it such a good basis for a competition engine were it's simplicity, minimalism, weight versus strength balance and compact exterior dimensions. Even against today's engines it's still remarkably compact for the power it's capable of producing when developed (I'm talking naturally aspirated here, 3 cylinder turbo engines of today are a different kettle of fish!)

I have amongst my collection of junk a Datsun L16 engine. As you can see in the picture the bottom end is quite different in architecture to a Ford Kent. There's really nothing much "Kentish" about it.

On the subject of Datsun crankshafts Datsun must have realized their initial mistake in overdesigning the original crankshaft for the L16. Later L16 crankshafts had considerable material removed from the webs in order to help make the crankshaft lighter and so improve engine performance and responsiveness. Pictures attached.

[alan.barker]

I like the Honda S2000 tasty.
Alan