Confused about the GT Engine...

[351CJ]

my understanding that the new 3 valve GT engine eill be all aluminum. which means it will be basically the old 4 valve block with 3 valve heads

Not quite correct. The 4.6L 3V block is a new casting. It is supposedly both more rigid and lighter than the old 4V aluminum block.

If you go back and search for the 05 Mustang press releases, they talk about the new block.


05 Mustang Overview Press Release

Because of its all-aluminum construction, Mustang's MOD V-8 – a member of Ford's modular engine family – weighs 75 pounds less than a comparable cast-iron design and stokes up 40 more horsepower than the 2004 engine. That's over 50 percent more power than delivered by the fiery, small-block 289-cubic-inch V-8 found under the hood of the classic 1964 model.

Electronic throttle control, faster engine management controls and the new three-valve cylinder heads with variable camshaft timing all contribute to this impressive output.

The three-valve heads with VCT allowed engine designers to use a higher compression ratio with regular 87-octane gasoline to maximize the energy used by every drop of fuel. Intake runners with active charge motion control valves also shape each combustion event for strong, low-end torque and maximum high-rpm power.

05 Stang Powertrain press release

The High-Tech Road to 300 Horsepower

Mustang's new 4.6-liter, three-valve MOD V-8 has its roots in Ford's modular engine family that spawned stalwarts like the F-150's workhorse 5.4-liter Triton™ V-8s and the 6.8-liter V-10 found in Super Duty F-Series pickups.

The V-8's deep-skirt, lightweight aluminum engine block provides optimum stiffness and strength, saving 75 pounds compared with a cast-iron design. Computer-aided engineering was used to reinforce key areas of the block, adding rigidity without weight.

The three-valve heads are smaller than the previous two-valve heads, reducing weight. They also offer a more direct, "ported" style path to the valves for better air flow at peak engine speeds. Magnesium cam covers suppress valve train noise and reduce weight. Taking weight out at the top of the engine helps lower the car's center of gravity and its roll-center axis, improving handling.

Ford's modular engine architecture lets Mustang share its aluminum heads with the new, 5.4-liter, three-valve Triton V-8 of the F-150, benefiting manufacturing efficiency. The heads in the F-150 and Mustang GT engines even share the same part number, including camshaft. However, sophisticated electronic controls, including the ability to regulate camshaft timing, allowed Ford powertrain engineers to tune both engines quite differently to achieve their individual missions.

The Mustang's torque curve is steeper and peaks at 315 foot-pounds at 4,250 rpm. The Triton delivers more total torque, at 365 foot-pounds, with peak torque coming in more quickly at 3,750 rpm.

In addition, a couple of the car rag preview articles on the 05 Stang mentioned that the block was new.

 

[351CJ]

Now if you assume that the correct weight for an assembled DOHC head is 60lbs.

I bet they weigh a lot more than that.

Also doesn't the Cobra engine have an aluminum intake manifold, that would add another 10 lb too.

 

[SVTdriver]

At this point I personally would bet that rumors of a V10 cobra mustang are greatly exxagerated. Especially with all the work Ford has been putting into it's V8 motors so far. There are a lot of V8 engines to choose from. Long before you get to the V10.

 

[SVTdriver]

I bet they weigh a lot more than that.

Also doesn't the Cobra engine have an aluminum intake manifold, that would add another 10 lb too.

So far I have found varying weight fors the DOHC heads. But complete with sparkplugs the highest weight I have seen is 68lb. But it has also been stated as low as 55lbs. With the hollow camshafts and all the other work they did to lighten it. Doesn't it seem just a little ridiculous to only gain 9 lbs but have all the extra expense of an aluminum block cast in Italy?

 

[351CJ]

Doesn't it seem just a little ridiculous to only gain 9 lbs but have all the extra expense of an aluminum block cast in Italy?

Look at it the other way, if they had used an iron block on the 99-01 Cobra engine, it would have weighed 60lb more than the iron block SOHC engine.

I'd bet that the intent of the aluminum block was just to keep the total weight of the 4V about same or less than the iron block 2V.

Again, doesn't the DOHC engine have an aluminum intake manifold? That adds a bunch of weight over the SOHC plastic manifold. Look at the FR-500 engine, FRPP used a magnesium intake manifold in order to save a few lb. Ford is putting out some major effort to shave weight off the mod motor.

 

[351CJ]

At this point I personally would bet that rumors of a V10 cobra mustang are greatly exxagerated. Especially with all the work Ford has been putting into it's V8 motors so far. There are a lot of V8 engines to choose from. Long before you get to the V10.

I agree, it is doubtful that we will ever see a V10 Mustang. I'd love to see a 351 CID, V10 Stang, but at this point we stand a much better chance of getting a Mustang model with a version of the new 6.2L Huricane V8 than of getting a V10. Bill Ford made a comment a while back about the Ford brand having a long and strong tradition built around V8 engines. That says it all.

I'd say there is a slight chance we'll see the V10 in a VERY limited production SE like a Cobra R, but I wouldn't hold my breath waiting for a V10 Mustang.

What Ford REALLY needs to do is make a low deck version of the upcoming Huricane with the same stroke as the 4.6L. This would work out to 5.3L. With it's larger 96.6mm bore (bigger valves which means better airflow) a 5.3L V8 like this would blow the present 5.4L away in a Mustang or similar car application. 400 HP normally aspirated would be a piece of cake for such an engine with 3V heads, normally aspirated. It would be exactly what Ford needs to compete with the 400 HP GM engine.

 

[TomServo92]

Aren't two new 3V engines (4.6L and 5.4L) the same block with a longer stroke in the 5.4L? That being the case, it seems fitting the 5.4 into the Mustang would be no problem since the physical dimensions (especially deck height) are the same.

 

[RandyB]

Aren't two new 3V engines (4.6L and 5.4L) the same block with a longer stroke in the 5.4L? That being the case, it seems fitting the 5.4 into the Mustang would be no problem since the physical dimensions (especially deck height) are the same.

They are still different deck heights, as before.

 

[TomServo92]

OK. I swear I read somewhere that the deck heights were the same on the new 3V engines but I can't find it anymore.

 

[351CJ]

OK. I swear I read somewhere that the deck heights were the same on the new 3V engines but I can't find it anymore.

If you read that, whomever wrote it is incorrect. The deck heights are exactly the same as the old engines. 8.937" for the 4.6 and 10.0787 for the 5.4L

 

[TomServo92]

If you read that, whomever wrote it is incorrect. The deck heights are exactly the same as the old engines. 8.937" for the 4.6 and 10.0787 for the 5.4L

I believe ya! Based on your previous posts, I know you tend to have your facts straight.

Maybe I dreamed it....