Dont shoot, 4.6 vs 5.0 question

Modular2v - you don't have to look far to see how almost every other manufacturer out there EXCEPT Ford managed both bottom end and 7K power with their 4v V8's. Pretty straightforward really. Most of them have variable length runner intakes, and variable valve timing and/or lift. Ford finally bit the bullet on variable valve timing with some of their 3-valves. But 4 valves and variable timing/runner length would've made the motor too expensive for the market they were trying to serve - to 5spd's point.

Your comment about improvements in bottom end torque compared to the 4v illustrates MY point -- it doesn't make sense to build OHC unless you're gonna take advantage of the breathing/revving capabilities it gives you. If bottom was what they were after, you can get it less expensively with a pushrod motor. Just ask Chrysler and GM. The 2v motor for the most part was initially deficient on both ends. It didn't have bottom, and it didn't take advantage of OHC's long suit - unobstructed ports and multi-valve layouts that breath. They ultimately developed their way back to 'break even' after making a fundamentally poor choice on architecture. Of the architectural choices - 1) 4 valve OHC V8; 2) completely re-engineered pushrod motor a la GM/Hemi; 3) 2v OHC -- the least attractive was number 3. Which is probably why the engine is no more.
 
My Father brought up the point and my Brother summed it up best. He said the 4.6 Mustang is powerful, but it doesn't have the low end torque. To which my Brother added, it's only 281 cubic inches.

Volumetricly it's a small engine. The LS1 is 5.6 litres - that engine is 346 inches BTW. The Dodge/Chrysler Hemi is like a 350 inches I think. Build a 350ish inch modular engine and it'll make some serious torque.

If you took a Lincoln Navigator DOHC and made it a big bore engine, ie..3.70" bore, it becomes a 358 inch engine. That would make torque and hp by the bucket load. 4.165" stroke is loooooonnnnnggggg. 3.55" stroke in teh 4.6 isn't too bad really. It's more than a 351. It's that dam tiny bore.

The engine is not at fault, it's the diminutive displacements it's burdened with.
 
Michael Yount said:
Modular2v - you don't have to look far to see how almost every other manufacturer out there EXCEPT Ford managed both bottom end and 7K power with their 4v V8's. Pretty straightforward really. Most of them have variable length runner intakes, and variable valve timing and/or lift. Ford finally bit the bullet on variable valve timing with some of their 3-valves. But 4 valves and variable timing/runner length would've made the motor too expensive for the market they were trying to serve - to 5spd's point.

Your comment about improvements in bottom end torque compared to the 4v illustrates MY point -- it doesn't make sense to build OHC unless you're gonna take advantage of the breathing/revving capabilities it gives you. If bottom was what they were after, you can get it less expensively with a pushrod motor. Just ask Chrysler and GM. The 2v motor for the most part was initially deficient on both ends. It didn't have bottom, and it didn't take advantage of OHC's long suit - unobstructed ports and multi-valve layouts that breath. They ultimately developed their way back to 'break even' after making a fundamentally poor choice on architecture. Of the architectural choices - 1) 4 valve OHC V8; 2) completely re-engineered pushrod motor a la GM/Hemi; 3) 2v OHC -- the least attractive was number 3. Which is probably why the engine is no more.
you say the engine is no more although it is being used in a number of ford vehicles still! when you say other companys 4 valve v8s.....WHO DO YOU MEAN? cadalliac is the only other company that i can think of off the top of my head with a dohc v8 and that motor produces a whopping 270hp! in my opnion ford did a pretty good job
 
Modular2v said:
you say the engine is no more although it is being used in a number of ford vehicles still! when you say other companys 4 valve v8s.....WHO DO YOU MEAN? cadalliac is the only other company that i can think of off the top of my head with a dohc v8 and that motor produces a whopping 270hp! in my opnion ford did a pretty good job

He was talking about the SOHC 4.6. It's only used in police Crown Vics still and they are fleet vehicles only. Everything is 3V or DOHC 4V now.

Nissan Titan has a 5.6 DOHC V8 that makes like 305 hp 4900 and 379 ft-lbs at 3600 rpm. Toyota has a 4.7 DOHC V8 with 271 hp in their pickup.

Fords own 5.4 DOHC makes 300 hp @ 5000 and 355 @ 2750.
 
Modular - I mentioned other manufacturers in a previous post, but for you I'll go through them again. The question ought to be who DOESN'T make 4v V8's - off the top of my head - Toyota, Lexus, Infinity, Nissan, Jaguar, Volvo, Audi, VW, Mercedes, Porsche, Lincoln, Aston-Martin, Rover and BMW all make 4v V8's in addition to Cadillac. Some are 'family' engines (Toyota/Lexus for example) - but by brand, MOST V8's are multivalve/DOHC. By the way, Cadillac's current version of the Northstar displaces 4.6L and makes 290 HP naturally aspirated, 440HP supercharged. It is a design derivative of the old Mercury-built ZR1 Corvette engine -- it's fundamental design is approaching 20 years old. So it's probably not the one you want to compare others to and conclude that the others are doing ok. The Northstar is WAY past it's prime. My comment about the 2 valve being gone -- check the 2005 product offering. The Stang, Explorer, 5.4L pickups are all 3 valve now. 4 valve versions available in some of the high-line stuff (Navigator for example). Is the base 4.6L 2 valve still available in the F150? Enlighten me - I don't know. When I read about the 3-valve showing up in so many vehicles, I (mistakenly it sounds like) assumed the 2V was gone. Sounds like you might still be getting it in pickups and Crown Vics.

tfm - it's not just a displacement issue. All of the dohc V8's mentioned above power 4 dr. sedans and sport utes that generally weigh in the 4200-5500 lb. range. Except for Cadillac, they are all SMALLER than 4.6L (most in the 4.0-4.3L range) -- and they make PLENTY of torque to power vehicles even heavier than the porky 05 GT (just for you 5 spd!). It's not simply a displacement issue. GM/Chrysler have essentially done with displacement what others have done with breathing/revs/technology (variable timing/runner length).

But - when you build it relatively small (281), you don't give it enough valves/port to breath and rev, and you don't equip it with available technology to let it work on the bottom and the top -- you end up, well, with the 2 valve modular.
 
Modular2v said:
you say the engine is no more although it is being used in a number of ford vehicles still! when you say other companys 4 valve v8s.....WHO DO YOU MEAN? cadalliac is the only other company that i can think of off the top of my head with a dohc v8 and that motor produces a whopping 270hp! in my opnion ford did a pretty good job
bmw uses several versions from 4.4-4.8 dohc V8s ranging from 270-365hp. all of these are n/a and don't rev higher than 6300. some of those have variable cam timing, and the only V8's in thier lineup with variable intake runners are sohc 4v design. imo ford has done an acceptable job with what the accountants have told them they had to work with. i still would rather see an "evolved" pushrod engine with a big bore, short stroke, and long rods. damn epa.
 
I think the 7 series V8's control engine speed entirely with variable lift. They have no throttles -- engine speed is controlled by infinitely variable valve lift; throttle by wire....just like the new GT, but completely different.
 
my personal opinions on this matter are that there is no clear winner between the two as both motors bring something to the table that the other doesnt. the modular motor is the new age of the mustang and i welcome it. i dont see to many cars such as the 03 cobra that can run 10's at the track and then drive home with the a/c on and get 20+ mpg. but these cars also dont have the fun to drive factor that a 5.0 does due to the torque band of a 5.0, let alone a stroker motor for the matter. it all depends on what the person preferences are as to which one is better.
 
Michael Yount said:
Just a note - the Explorer is classified as a truck; in the mid-90's the emissions standards it had to meet weren't as stringent as for a car. You were right the first time - one reason the 4.6 came into being (since 2002 even in the Explorer) was because it was engineered to comply with ever tighter emissions regs. The 5.0L wouldn't have been able to get there without a complete re-engineering. Ford made a choice to go in a different direction. And given GM's success with the LS1/2 variants, as well as Chrysler's recent 'hemi' boom, there are those even at Ford who are wondering if they shouldn't have stuck with a clean sheet pushrod approach much as GM and Chrysler (hemi) have. It has made for a smaller, lighter power plants that are certainly not suffering in the power wars. (GM's 6.0L at 400HP and Chrysler's 6.1L at 425HP).

The basic benefit of OHC's are 2-fold: 1) it removes the pushrod from the picture completely freeing up intake port size/shape; and 2) valve train weight is generally reduced allowing higher revs, or equal revs with lighter springs (less losses). The downside is size/packaging/cost -- makes for a taller/wider/more expensive engine. All you need do is look under the hood to see how large the (especially) 3-valve or 4 valve mod motors are compared to Ford/GM pushrod offerings. And look at prices for aftermarket heads and cams for OHC stuff (you need two or 4 of them). Most automotive engine designers would tell you it probably only makes sense to go OHC if you're gonna fill up the chamber with valves (4 valve) and take advantage of the breathing capabilities. You'll pretty much see this at work with almost all imported V6/8's - nearly all of them are 4 valve (BMW, Lexus, Audi, VW, Infinity, Honda, Toyota, Acura, Volvo, etc., some Mercedes exceptions in years past). So many scratched their heads over Ford's decision to go with a 2-valve OHC engine. And even Ford has partially remedied that as all mod-motors are now 3 or 4 valve.

I did pick up this interresting little tid bit from Al Kirschenbaum's book concerning 5.0 emissions in the Explorer. Evedently, the 1997+ GT40P 5.0 produced much LOWER emission levels than even the 4.6. Also, ads from 1999 stated "as a LEV (Low Emissions Vehicle), the new Explorer actually runs cleaner than most cars on the road today." Ford neglected to make any direct comparsions to the 4.6 to avoid getting egg all over its face. With these facts at hand, I don't think the 5.0 would have needed a complete redesign to meet future demands.
 
Michael Yount said:
....and bmw has it's own Five-Oh.....

V10 -- 500 HP somewhere up around 8000 rpm
don't forget the original 5.0 engine in the E39 M5 and Z8. as far as the 7 series engine, it is a 4.6 sohc with variable valve lift(valvetronic), variable cam timing(vanos), and infinetly variable intake runners(deiza). the engine has a throttle body, but is only used for a backup and stays open 99% of the time. it makes 325hp/340tq, but feels like it has a roots blower because of the broad torque curve. the newer 6.0 V12 has a similar setup only adding direct injection.
 
Michael Yount said:
My comment about the 2 valve being gone -- check the 2005 product offering. The Stang, Explorer, 5.4L pickups are all 3 valve now. 4 valve versions available in some of the high-line stuff (Navigator for example). Is the base 4.6L 2 valve still available in the F150? Enlighten me - I don't know. When I read about the 3-valve showing up in so many vehicles, I (mistakenly it sounds like) assumed the 2V was gone. Sounds like you might still be getting it in pickups and Crown Vics.

I got curious, so I checked and the 4.6 SOHC F-150 is still a 2 valve engine. That will likely change in the next year or so I suspect. The Crown is 2V SOHC.

The Explorer was 2V and in 2006 is going 3V.

Looks like the rest of SUV line is still 2V. I'm guessing that will change too.
 
tjm73 said:
He was talking about the SOHC 4.6. It's only used in police Crown Vics still and they are fleet vehicles only. Everything is 3V or DOHC 4V now.

Nissan Titan has a 5.6 DOHC V8 that makes like 305 hp 4900 and 379 ft-lbs at 3600 rpm. Toyota has a 4.7 DOHC V8 with 271 hp in their pickup.

Fords own 5.4 DOHC makes 300 hp @ 5000 and 355 @ 2750.
i know he was only talking about the 2valve motors! I see them in excursions (5.4) expeditions (4.6) crown vics, lincoln town cars, mercurys etc and the 04/05 f-150 single cabs still sport the 2 valve on occasion my brother has one....and all those dohc motors just listed in the last post are larger displacement motors than the 4.6........my point is that the 2valve 4.6 is pretty stout for what it is
 
Modular2v said:
i know he was only talking about the 2valve motors! I see them in excursions (5.4) expeditions (4.6) crown vics, lincoln town cars, mercurys etc and the 04/05 f-150 single cabs still sport the 2 valve on occasion my brother has one....and all those dohc motors just listed in the last post are larger displacement motors than the 4.6........my point is that the 2valve 4.6 is pretty stout for what it is

For it's displacement and valve configuration you are correct.
 
tjm73 said:
Three letters..... NVH, and emissions. Period. That's why Ford changed to a different engine.

NVH (Noise, Vibration, Harmonics) was significantly reduced in the 4.6. Drive both back to back (I do regularly) and you'll understand how much smoother the engine runs and sounds. No pushrods makes the NVH values significantly lower. Rotation of cams is much smoother than the up, stop, down, stop, repeat action of the pushrod. It makes vibrations, noise and harmonics.

Emissions. The 4.6 was easier to make meet the stricker emissions guidelines that came on board around the mid 90's and moving forward.

In addition, they can have tighter tolerances and longer lasting engines with fewer warrenty claims.

They should have simply redesigned the 5.0 keeping the 4 inch bore 3 inch stroke dimension and giving it a totally new block and OHC's. That would have been a beast.

Have you ridden in any 5.3L V8 equipped GM vehicle lately?I'd put it up against any Modular ford puts out as far as NVH...The 5.3L in my Yukon makes 290 hp./320 torque...The 4.6 liter in the GT of the same year made what?280hp or so?

I know that it's a "truck"engine,but hell,the LS1 is all you need to know as far as "how far in technology" can the pushrod go debate..Not to mention the lS2,LS6,ect....GM simply refined a design that already worked..And the gas mileage between an 02 GT and an 02 Z28(for comparison) was pretty compareable....I like the 4.6L and all of the Modular motors,but I think Ford jumped ship way to early with the Windsors...JMHO..Makes me wonder how the 5.0L with todays technology would be doing... :shrug: