what has more potential for power?

[HULK_I6T]

With the same displacement which design of motor has the better potential for power?

4000cc inline 6 or 4000cc V8?

Assuming a modern design in both such as multiple valves and cams.... which design would be more likely to produce more power with the same displacement.

[Falcon SXR8]

Probably the same power but the v8 will sound better doing it so it wins

[ratter]

what bore and stroke of each combination?

[Sox]

Originally Posted by ratter

what bore and stroke of each combination?

I would imagine that in a hypothetical question such as this, we can assume that a bore and stroke ratio optimised for each cylinder config.

Otherwise it's a huge can of worms with numerous answers.

Considering this, the maximum outputs for each engine should be mostly similar.

[Franco Cozzo]

That Toyota 1UZFE 4L V8 is a pretty neat engine:

The 4.0 L (3,968 cc or 242.1 cu in) all-alloy 1UZ-FE debuted in 1989 in the first generation Lexus LS 400/Toyota Celsior and the engine was progressively released across a number of other models in the Toyota/Lexus range. The engine is oversquare by design, with a bore size of 87.5 mm (3.44 in) and stroke of 82.5 mm (3.25 in).[1] It has proved to be a strong, reliable and smooth powerplant with features such as 6-bolt main bearings and belt-driven quad-camshafts. The water pump is also driven by the cam belt. The connecting rods and crankshaft are constructed of steel. The pistons are hypereutectic.

There is a lot of supercharger/turbo kits out there for them too.

[mechanic]

Originally Posted by Big Damo

That Toyota 1UZFE 4L V8 is a pretty neat engine:



There is a lot of supercharger/turbo kits out there for them too.

That sure is oversquare, at what rpm does it get it's HP and Torque?

[Franco Cozzo]

Originally Posted by mechanic

That sure is oversquare, at what rpm does it get it's HP and Torque?

Japanese versions are rated at 191kW at 5400 rpm together with 353Nm at 4600 rpm, while Australian delivered versions (from early 1990) make 1kW and 3Nm less. It is claimed that 90 percent of peak torque is spread from 2000 to 5600 rpm but, curiously, it doesn’t feel that way – the engine seems to come alive at around 4000 rpm.

Its not overly torquey, but it was fitted to the Lexus LS400 which was a big luxury car at the time in the late 80s/early 90s.

Someone on Fordmods has one in an E Series Falcon.

[mik]

Originally Posted by Big Damo

Its not overly torquey, but it was fitted to the Lexus LS400 which was a big luxury car at the time in the late 80s/early 90s.

Someone on Fordmods has one in an E Series Falcon.

They are a nice little engine, I have one in my ls400, my young brother has 3 cars with 1uz donks, soarers (one super charged one na)and one sleeper na in a smaller vehicle, and I have done the glass of water trick on the engine, they really are a nice smooth donk.

[LoudPipes]

I'll take the one with the most useable torque.

[Nikked]

More cylinders = more valve area...

Does that mean more power though?

String, how long...

[Sox]

Originally Posted by Nikked

More cylinders = more valve area...

Does that mean more power though?

String, how long...

On first look, we might think this.
However if the bore/stroke is optimised for both, the valve area can be roughly the same.

[AU1XLS]

If you don't like posts by any member put them on ignore
Anymore off topic posts and or digs will result in warnings being given

[FPV GTHO]

The V8 will have more exhaust pulses allowing a bigger exhaust without loss of scavenging, lighter pistons and smaller stroke allowing higher rpm peak. The 6 cylinder will be simpler and likely produce more torque though.

[mik]

Potential power = how big is your bank account ???

[Franco Cozzo]

Originally Posted by mik

Potential power = how big is your bank account ???

Thats it, its all about how much you want to spend, everything is possible with cars the only limit is $$$ and the five-oh.

[dragons90]

I6 is too long for most cars that's why they go v6 or v8

[GASWAGON]

Still an I6 will use less fuel compared to a V8 plus they're very balanced even stock bottom end.....Look at the Nissan 3.0ltr engine Holden put in the VL commo....Great injected motor with only 3 ltrs.

[FPV GTHO]

Why would an I6 use less fuel, everything else equal?

[mik]

Originally Posted by FPV GTHO

Why would an I6 use less fuel, everything else equal?

Less friction, less cranking pressures.

[XR Martin]

TVR made a 300kw+ 4L Inline six back in the late 1990s

[Bossxr8]

One factor to consider is the more cylinders, the more friction would be generated from 8 pistons/conrods etc Vs 6 pistons/conrods etc.

But then again those 6 cylinders would have to be bigger so maybe it would balance out. I doubt there would be much in it at all, all things being equal.

[HULK_I6T]

Why not a huge 4000cc 4 cylinder with vtec?

Discussion not limited to other types of designs. Just looking at a certain displacement and considering the options.. Let's say 4000cc

[Franco Cozzo]

Originally Posted by HULK_I6T

Why not a huge 4000cc 4 cylinder with vtec?

Discussion not limited to other types of designs. Just looking at a certain displacement and considering the options.. Let's say 4000cc

Cummins 4BT, 3.9L 4 cylinder lol.

[Vesper Martini]

Originally Posted by HULK_I6T

Why not a huge 4000cc 4 cylinder with vtec?

Discussion not limited to other types of designs. Just looking at a certain displacement and considering the options.. Let's say 4000cc

A large capacity 4 cyl will have a Huge Bore and stroke will result in a low revving engine with lots of Torque.
wouldn't be very smooth either

not really suited for Hondas V-Tec

[XP6]

Given the same specs the V8 should pip the six in torque because of the extra power strokes per single revolution of the crank.

[yearby]

Getting back to the question-

"With the same displacement which design of motor has the better potential for power? 4000cc inline 6 or 4000cc V8?

The answer is the V8 and here is why.

Divide the 4000cc by 6 for the inline 6 cylinder and you will get 666.66cc
now
Divide the 4000cc by 8 for the V8 and you will get 500cc

First thing to notice is that inline 6 has a greater volume per cylinder than the V8 and this greater volume affects the amount of time for the flame front to cross the combustion chamber. The larger the volume, the more time the flame takes to cross the camber.

Now we are talking in micro seconds here, but if you think about the size of the atoms/molecules colliding inside the combustion chamber and their relationship to the size of the combustion chamber this a big deal on their scale.

Now the engine with the fastest complete burn time is the engine with the most potential, in this case the V8.

1. The V8 with it's faster burn time allows the torque curve to be raised up the rev range thus producing more power.

2. The faster burn time allows the fuel mixture to be leaned, (that is to run a leaner mixture under full throttle), a leaner mixture burns slower but releases more energy (heat) than a richer mixture, and this is compensated by the smaller combustion volume.

The evidence to support this would be the very high revving motorcycle engines doing 10,000 rpm plus. I guess it would be like bolting 8 small high revving engines together.


Peter

[Nikked]

Could having more cylinders have an advantage in rotating mass? Smaller piston size, and lighter...more free revving?

[Vesper Martini]

Originally Posted by Nikked

Could having more cylinders have an advantage in rotating mass? Smaller piston size, and lighter...more free revving?

I would say yes, where as the lesser cylinder engine could potentially produce more Torque.

[Nikked]

Or cars, for that matter...

[Crazy Dazz]

There are some problems with large 4 cylinder engines. Not really sure, but I think it has something to do with the mass of the moving components (pistons, rods, and crack) increasing relative to the mass of the block. (They're balanced vertically but not horizontally?) That's why in the past engines much bigger than 2 litres had balance shafts.
With modern engines it seems 2.4~2.5 is ok, and diesels upwards of 3 litres.
I think straight 6's and V8's are better balanced in all axis.

The reality is that if the bore & stroke are similar, you're going to have similar potential. As somebody said, how long is a piece of string. It really is a question of packaging. In the past I reckon that under any given bonnet, you could get better induction and exhaust with the angled cylinders of the V8. Not so sure that still applies with EFI and forced induction.