This thread is about normally aspirated V8 vs forced induction what does a 2.2D have to do?

 

Other notable manufacturer moving to 6 cylinders...

Report: Next BMW M3 Will Have Inline-6, Not V-6 - Rumor Central

 

Which make this thread a total contradiction as inline 6 are by no means as efficient as V6 configuration...go figure.

 

The 1995-1997 XJR/6 were pretty nice cars. Supercharged inline six cylinder displacing 4.0 litres. The Jaguar flagship model for those years.

Except for the Mk I, all Toyota Supras have been six cylinders. The Mk III and Mk IV being turbocharged. The Supra's are Toyota's flagship models.

Both were highly desirable, premium priced cars.

 

See the title, and see where the thread has wandered.

 

By what criteria?

BMW has always been known for great inline six cylinder engines. Inline sixes are inherently perfectly balanced.

Given the BMW tradition, they may have met some buyer pushback when it comes to V6 configurations.

 

I have yet to see any comments on how Jaguar has designed the new V6. My earlier comment on Jag not following the direction of Formula 1 was not picked on. In F1 they basically took their V10 & chopped of 2 cylinders. Jaguar has taken a different approach, they are using the V8 block with the back 2 cylinders eliminated & counter weights installed. Take a close look at the photo of the engine it is a V8 crank.

 

90 degree V6 has some packaging advantages and can be made to run as smoothly as a more conventional 60 degree V6. Ferrari also built their famous 65 degree V6 (and V12) which was never criticized for unbalanced vibration.

 

I never said six cylinders are not well balanced. They are. I have a BMW 3.0CS and its smooth. However a smaller displacement V6 will outperform it as in my 2.6 V6 Ford Capri. Just plain physics. Thats why there are no
V12 or V8 not practical and you can get more power from a V or W configuration. I rest my case.

 

If they use a V8 block how is that compact ???

 

V8 is compact compared to an inline 8.

It is suggested that the new V6 would use 3/4 of the V8 block, not the whole thing. It also would use a shortened crank.

It is not possible for a V6 to use a V8 crank or any part thereof.

To suggest that a V engine can make more powertrain an inline engine is over simplified. For a road engine this simply isn't true.

Also, an inline four will make more power than a V 4. This is one reason the most powerful V8 engines are flat crank engines, two inline fours cast in one block and on a common crank.

It depends on a number of factors.

The main advantage V engines have is very short and rigid crankshafts. However, firing order and second order imbalances have to be addressed. Intake and exhausts are tricky to optimize also.

 

Hmmmmm..........Interesting topic. The in-line engines rule when it comes to large block diesels. When you get to 1000++ HP in big diesels, they are all in-line, normally 6 cylinders. Old style were V type, but not anymore.

 

Jagular we are aware you know it all, however it is a V8 block & crank with counter weights that they are using. I will try & scan a photo as I am unable to copy it.

 

This is true, both my supras are inline V6 and those suckers put out over 1K RWHP on stock blocks. Total beast of a inline 6!!!

 

A V6 cannot use a V8 block. It has to have only 6 holes in it. 8-)

I concede I cannot visualize how an 8 cylinder engine's crankshaft could be modified to be used in a V6 but it would still have one less journal (at least) and one less main bearing. I think the journals would have to be spaced differently to accommodate the V6 firing order and timing.

I understand that a 90 degree V8 block casting design can be used to also cast a V6 at 90 degrees, and that modern engineering techniques can even make such an inherently unbalanced design run smoothly. It will still not be a V8 block.

 

Introduction

 

Here is the photo that is in the first post on this subject. Jagular would you be so kind to tell me what the big gap is before the flywheel? As I said before it is a V8 block & crank with counter weights in the back.

 

That's a better view of a picture I've seen before. It still isn't a V8 crank. It is hard to see if the three crank pins are double and offset as one would expect, or common as for a normal V8 crank. You can see it isn't a 90 degree bent crank nor a flat crank. It is definitely machined only for a V6.

As I suspected there is no fourth connecting rod journal and one less main bearing journal (V8 cranks typically have five main bearings). At first I thought the fifth main bearing journal was there but not machined and that may be the case. But the fourth connecting rod journal(s) definitely isn't there. There is space for it but it is not there. I've never seen such a long tailed crank. Looks like the only function for the extended portion is to house the crank position sensor. I do note the odd extra crank weight unusual also in that it is attached to the center of the crank, not an offset journal.

Hard to see why this design would be adopted as the engine is longer than it needs to be. Although, if I think about it, this crank could be easily machined on the same robotic lathe as the V8 cranks, the long tail making it the same length. The main reason for using a chopped off V8 block (and presumably heads) is to facilitate machining of two engines on one production line. Jaguar has built its own engine plant. Previously their V8 was built by Ford in Wales,UK while the V6 is a Cleveland or Canadian Ford product. They don't build their own diesels so maybe Jaguar is trying to use one engine line in their new plant for both gasoline engines.

 

Here is a link to the new Jaguar V6 engine