I was messing around on the net at work today and decided to look into the new Ford GT that's coming out. I don't understand how they use the 5.4 engine, supercharge it and still only produce 92.6 hp per liter. To me, any modern engine should be able to do that N/A. Especially on a car like this one. And I noticed that it has a 10 quart oil capacity! Is this normal? What's this car supposed to be going for again? $140k? Sheesh! I can't wait for the HSC!
Ford GT
- Thread starter White92
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White92 said:
From everything I have read about the Ford GT it is an amazing automobile. I applaud Ford for coming out with such a wonderful car when they were in such financial trouble. You might be the only person I know that would complain about 500hp! This engine develops its power at lower RPM's which give it a lot of low end grunt. Most of the engines that you are refering to that develop above 90hp / liter do it at a much higher RPM with significantly lower torque. The reason it uses so much oil is because it has a dry sump oil system. This is what all true race cars have and is very necessary to always provide oil to the engine even during hard cornering. I have heard of a few NSX's that have burnt down because of oil starvation on the track. My 911TT uses 13 quarts of oil is this bad? Maybe it is good that you don't want the GT because if you did you would have to pay significantly over the price you mentioned to get one as all of the cars are already sold. I also believe the HSC (new NSX) won't perform as well as the GT and in my opinion doesn't look nearly as good.
I guess that is why they make many different types of cars.
Oh, don't get me wrong. I think the new GT is going to be an awesome car. I'm not in the market to buy one either. I was just wondering why they were using the 5.4 liter engine. Is this the same engine that they use in the mustang? I'm sure it's stronger internally. If it is the same engine, I would think that they would have designed a new engine for such an exclusive car rather than beefing up a Mustang engine and putting a supercharger on it. If it's a different engine, then I take back that statement. I guess the oil capacity thing just threw me when I saw that. I don't know alot about higher end oiling systems, but what you say makes sense. Thanks for the schooling.
The Ford GT's motor will be built by Saleen, and is probably extremely similar to the S7's engine. Saleen and other manufacturers often use Ford blocks or base their engines on Ford blocks (I think perhaps Koenigsegg, Aston Martin, etc. also) because they are good engines to build off of.
There is absolutely nothing wrong with using an engine from a "lower" model car, even if its a Mustang. That just goes to show how well the original engine was designed/how flexible it is, and mind you there are still plenty of differences between a normal 5.4L Ford V8 and Saleen's tuned monster ~ just as there are vast differences between the C-block Legend engines and the DOHC VTEC iterations that power your NSXs.
There is absolutely nothing wrong with using an engine from a "lower" model car, even if its a Mustang. That just goes to show how well the original engine was designed/how flexible it is, and mind you there are still plenty of differences between a normal 5.4L Ford V8 and Saleen's tuned monster ~ just as there are vast differences between the C-block Legend engines and the DOHC VTEC iterations that power your NSXs.
Rarely do engine power ratings scale along with size.
For example, the 2.1 L S2000 engine puts out 240hp @ 7,800 RPM. One would think that a similarly designed 4.2 L V8 would be able to generate 480hp. But it doesn't work that way.
There are frictional and inertial losses that get in the way. I would expect a 4.2 L S2000 V8 to produce about 400hp.
The 500hp Ford V8 is indeed an accomplishment and I think it's going to be a great engine for a great car.
-Jim
White92 said:
I do agree to some extent on why not design a new engine. But as a few other members have stated its often times common and much easier to improve on something already exisiting
Remember the Mclaren F1 is just a BMW V12 with some work done
I would love to have a ford GT... Tried to get the parents intrested but they decided on the jet timeshare
they are just not as into cars o well. Can't wait till i catch one out on the streets or a track 
Remember, the GT 40 just gave a serious spanking to the 360 Stradale and the GT3 in a recent track test! Pushrod engines may be "low tech" but they still make big reliable power.
FF Drifter said:
Ford owns Aston Martin and Jaguar. That's why they use Ford V8s.
The Ford GT engine is hardly a low tech pushrod design.
It's a DOHC all-aluminum V8 with a supercharger and sequential multi-port electronic fuel injection with 2 injectors per cylinder. It has forged internals and it probably doesn't weigh that much more than the engine in our NSX.
In fact, I'd love it if Honda saw fit to purchase these engines for the next-gen NSX.
I should read more. I had no idea it was dohc. I was able to see a prototype two years ago at the Concorso Italiano and last year I even had one of the original designers sign a poster of it for me, er... my step son. Beautiful car, but I've yet to see one running though.
Jimbo said:
Wouldn't that be wild!
Jimbo said:
Im not sure I understand why this would be the case.
Suppose you took 2 separate S2000 engines and you connected their crankshafts end to end to make an inline 8. They share nothing other than the crank (and assume that it doesnt snap under the load).
Why wouldnt this 4.0L combination make 480 HP?
Each engine still has the same amount of rotating mass. Each engine still has the same contact area and friction. Where do these extra frictional and inertial losses come from?
Please explain.
-- Joe
Joe,
OK. Let me try and explain...
OK. Let me try and explain...
Oops. I hit the wrong button...
Anyway. Let's first look at a little chart I made up...
I gathered data at random for a number of performance oriented cars. I sorted the list by the amount of hp per cc of displacement.
Notice how for the most part the smaller engines do better than the larger engines. The S2000 is really an amazing accomplishment considering that it's naturally aspirated.
So why is this?
Let's use the S2000 engine as an example. If we had two of these engines running side by side each engine would produce 240 hp for a total of 480 hp.
Now let's imagine that both engines just so happened to be running in sync. That is to say that when cylinder #1 fired in the left engine that cylinder #1 in the right engine fired at the same time and so on for the other cylinders in the firing order. So we got 480 hp, OK?
Now let's imagine that we designed a new V8 block that essentially merged the two inline 4 blocks together (or an inline 8). Do we still have 480 hp?
No, because if we look at the firing order of this engine, only one cylinder is firing at any given time. Let's say the firing order is 1-8-3-6-4-7-5-2.
So when one cylinder is firing - it has to overcome the frictional forces in the engine for all the other cylinders (i.e. valve springs, cylinder wall friction, compression, etc).
To further make the point - imagine that we extended this block to be a V16. That is to say we put two of these V8s together front-to-back?
Would we have 960 hp?
No, because the losses would be even worse because one cylinder has to pull the load for the other 15.
Of course there are also issues of balance and smoothness and that's one nice thing about V12s and V16s. And there's issues of heat efficiency with small vs large engines, but that's another story.
Does this make sense?
PS: You might ask why couldn't two cylinders fire at the same time. I suspect that the very slight unpredictability of ignition and flame fronts would wreak havoc with the internals. Like if one cylinder happened to fully burn 3 microseconds before or after its partner all kinds of stresses and problems would be seen. But this is just a guess on my part.
Anyway. Let's first look at a little chart I made up...
I gathered data at random for a number of performance oriented cars. I sorted the list by the amount of hp per cc of displacement.
Notice how for the most part the smaller engines do better than the larger engines. The S2000 is really an amazing accomplishment considering that it's naturally aspirated.
So why is this?
Let's use the S2000 engine as an example. If we had two of these engines running side by side each engine would produce 240 hp for a total of 480 hp.
Now let's imagine that both engines just so happened to be running in sync. That is to say that when cylinder #1 fired in the left engine that cylinder #1 in the right engine fired at the same time and so on for the other cylinders in the firing order. So we got 480 hp, OK?
Now let's imagine that we designed a new V8 block that essentially merged the two inline 4 blocks together (or an inline 8). Do we still have 480 hp?
No, because if we look at the firing order of this engine, only one cylinder is firing at any given time. Let's say the firing order is 1-8-3-6-4-7-5-2.
So when one cylinder is firing - it has to overcome the frictional forces in the engine for all the other cylinders (i.e. valve springs, cylinder wall friction, compression, etc).
To further make the point - imagine that we extended this block to be a V16. That is to say we put two of these V8s together front-to-back?
Would we have 960 hp?
No, because the losses would be even worse because one cylinder has to pull the load for the other 15.
Of course there are also issues of balance and smoothness and that's one nice thing about V12s and V16s. And there's issues of heat efficiency with small vs large engines, but that's another story.
Does this make sense?
PS: You might ask why couldn't two cylinders fire at the same time. I suspect that the very slight unpredictability of ignition and flame fronts would wreak havoc with the internals. Like if one cylinder happened to fully burn 3 microseconds before or after its partner all kinds of stresses and problems would be seen. But this is just a guess on my part.
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Hi Jimbo,
Thanks for responding.
(White92 - Sorry, I realize this is getting off topic, but I just got to know.)
OK, I still dont get it.
I dont see how staggering the firing order affects the net amount of friction. The combustion cycle lasts for 180 degrees, but a cylinder fires every 90 degrees in the V8. At any given time, 2 cylinders will be in the combustion cycle. So you end up with 2 cylinders trying to overcome twice the frictional forces (relative to an inline 4), or basically 2 cylinders pushing and 6 cylinders dragging. This is the same ratio as the inline 4.
Applying this to your 16 cylinder example, a cylinder will fire every 45 degrees, or basically 4 cylinders will be in varying stages of the combustion cycle. 12 will be dragging, not 15. Again every cylinder in the combustion cycle will be dragging 3 other cylinders.
As long as all cylinders fire over the course of 2 rotations, I dont see why the power output will not be the same whether you fired them staggered, synchronized, or all at once. The main difference should be in the amount of vibration you get.
Boxer engines do exactly this and they have been around for ages. This is a common engine configuration with porsches and subarus.
Again, I do not understand why you could not graft 2 inline 4's into this configuration and get the same 120HP/L number. Aside from the arrangement of the crank, everything else is the same as in the base engine.
I dont understand this one either. If we are merely grafting 2 inline 4's together, we are not changing the volume or shape of the combustion chamber. The intake and exhaust would be kept separate between the banks. How will doubling the displacement in this fashion affect the heat efficiency of the engine? (Ignoring the need for a bigger radiator.)
-- Joe
Thanks for responding.
(White92 - Sorry, I realize this is getting off topic, but I just got to know.)
Jimbo said:
OK, I still dont get it.
I dont see how staggering the firing order affects the net amount of friction. The combustion cycle lasts for 180 degrees, but a cylinder fires every 90 degrees in the V8. At any given time, 2 cylinders will be in the combustion cycle. So you end up with 2 cylinders trying to overcome twice the frictional forces (relative to an inline 4), or basically 2 cylinders pushing and 6 cylinders dragging. This is the same ratio as the inline 4.
Applying this to your 16 cylinder example, a cylinder will fire every 45 degrees, or basically 4 cylinders will be in varying stages of the combustion cycle. 12 will be dragging, not 15. Again every cylinder in the combustion cycle will be dragging 3 other cylinders.
As long as all cylinders fire over the course of 2 rotations, I dont see why the power output will not be the same whether you fired them staggered, synchronized, or all at once. The main difference should be in the amount of vibration you get.
Boxer engines do exactly this and they have been around for ages. This is a common engine configuration with porsches and subarus.
Again, I do not understand why you could not graft 2 inline 4's into this configuration and get the same 120HP/L number. Aside from the arrangement of the crank, everything else is the same as in the base engine.
I dont understand this one either. If we are merely grafting 2 inline 4's together, we are not changing the volume or shape of the combustion chamber. The intake and exhaust would be kept separate between the banks. How will doubling the displacement in this fashion affect the heat efficiency of the engine? (Ignoring the need for a bigger radiator.)
-- Joe
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