Dont shoot, 4.6 vs 5.0 question

J_Squared

Active Member
Jun 28, 2005
98
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28
Buffalo, NY
OK now i know there is a ton of controversy over which is better blah blah. i like them both, but i am curious how the OHC makes any real difference. is it like better response or something, what is the performance difference. guess i just dont see any real difference other than placement of the cam between that and the OHV. i feel kinda dumb asking but eh, curiousity is getting me. thx.
 
Bang! I shot you. Just kidding. The truth is, an internal combustion engine does not "care" how its valves are actuated, only that it recieves the best air/fuel mixture possible. While 4.6s turned out to be descent motors, it wasn't always so. '96 was not a good year. Fords line was that the 4.6 was technically superior to the 5.0 which wouldn't meet the tightening emission regulations. The truth? The first 4.6s didn't have the balls of the old 5.0 and the 5.0 DID turn out to be a very clean motor (as witnessed by it continued development in the Explorer line). Let's face it, Ford was also trying to cut cost by offering one basic motor platform to suit all its needs. 4.6s aren't called "modular" for nothing. Ford probably though they'd be able to "control" more aspects of the mod motors which gives them a better grip on emissions, economy and performance. GM however seems to being doing fine with push rods still. Me? I'd take a 5.0, but that doesn't make the 4.6 a bad motor by any means. Just personal preference.
 
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 agree with Micheal on this... By switching to modular (OHC) you can eliminate the pushrod.

Less moving parts means higher RPM cababilities in an engine that comes from a factory (Production build tolerances and all that stuff)
 
....so the challenge with the original mod motor becomes clear. Ford simply didn't take advantage of the design's strong points with the 2-valve motor. They achieved all the downside, with little of the upside. And of course, the car it went in got heavier - so performance was worse. I don't know what they were thinking.
 
I have a simple question related to this topic.

Have there been any modular, normally aspirated, OHC, motors that are at or very near the 5 litre diplacement that make 450 - 460 FWHP and 400 FWTQ?
 
None that I know of come close when they are Naturally Aspirated. The motor is more effecient, but not at making power.

Ford was trying to make their cars more advanced than GM. GM pounded on the Mustang from 96 on... Only now when there are no more camaros / firebirds does the mod motor really make sence in my eyes. (nothing against it) I just never understood
 
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.
ummmmm the 2valve is technically "bigger" than the 3 valve as far as sheer mass concerned... and the 2 valve has made HUGE performance strides in the past 4 years!
 
Modular2v said:
ummmmm the 2valve is technically "bigger" than the 3 valve as far as sheer mass concerned... and the 2 valve has made HUGE performance strides in the past 4 years!


Yes, it has. The mod motors, when they were 2V, have come a long way since 1996. But just imagine what the little 302 would have been like if Ford had stuck with it in the Mustang. Sooner or later Ford would have put better heads and intakes on them and maybe we would have been able to keep up with the F-body's.
 
They shouldn't have had to make 'progress' -- it should've been a 4 valve motor from the start guys --- that's the whole point. They didn't take advantage of the OHC layout's benefits even with the 'improved' 2-valve.

Daggar - FRPP sells a 'cammer' crate engine; 5.0L; 4 valve/cylinder; they advertise it this way: "the engine will exceed 400 bhp and have a very broad torque curve, peaking over 365 lb-ft." Suggested retail on that puppy is $14,995.00.
 
J_Squared said:
OK now i know there is a ton of controversy over which is better blah blah. i like them both, but i am curious how the OHC makes any real difference. is it like better response or something, what is the performance difference. guess i just dont see any real difference other than placement of the cam between that and the OHV. i feel kinda dumb asking but eh, curiousity is getting me. thx.

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.
 
tjm - your last comment is the most interesting though. Chrysler and GM have achieved similar levels of efficiency, emissions compliance and low NVH with their redesigned pushrod motors. Why did Ford choose to go OHC vs. pushrod? That's the question.

I think they wanted to have a motor that they could be proud of globally. Everyone else's V8's - non-domestic - were headed into 4-valve OHC architecture. Problem is Ford's price structure/market couldn't bear the cost of a 4-valve V8; so they built what their market would bear at the time - a less expensive 2-valve version. My 'guess'.
 
Michael Yount said:
They shouldn't have had to make 'progress' -- it should've been a 4 valve motor from the start guys --- that's the whole point. They didn't take advantage of the OHC layout's benefits even with the 'improved' 2-valve.

Daggar - FRPP sells a 'cammer' crate engine; 5.0L; 4 valve/cylinder; they advertise it this way: "the engine will exceed 400 bhp and have a very broad torque curve, peaking over 365 lb-ft." Suggested retail on that puppy is $14,995.00.

Whoa! That's a healthy price tag!
 
Michael Yount said:
tjm - your last comment is the most interesting though. Chrysler and GM have achieved similar levels of efficiency, emissions compliance and low NVH with their redesigned pushrod motors. Why did Ford choose to go OHC vs. pushrod? That's the question.

I think they wanted to have a motor that they could be proud of globally. Everyone else's V8's - non-domestic - were headed into 4-valve OHC architecture. Problem is Ford's price structure/market couldn't bear the cost of a 4-valve V8; so they built what their market would bear at the time - a less expensive 2-valve version. My 'guess'.

I know. And I think you are right. I think Ford really wanted to try to move themselves up-market and sell themselves as a technologicly advanced company. Make them into a real forward thinking, energetic company. Well, that's the tail end of the Nasser era. one that will go down as one of the worst in Ford's overall history. He ignored cars, and it's gonna take at least decade to fix. I believe it's under his leadership that they nearly killed off the Mustang (remember the Probe situation folks) and it's under his watch that the 4.6 was given the green light over the 5.0. And I'll bet that their was another plan that basically redesigned the 5.0. The 5.0 was it's peak of popularity and had mad street cred and it got killed for a smaller engine. Can some one say mega F-up?

As proof of this, it's widely rumored that Ford is developing a new pushrod engine. They say it's for trucks because trucks need low end torque and the SOHC/DOHC can't deliver the goods for some reason. But if it's smaller, lighter, makes as much or more power and it's cheaper to build, while being environmentally clean, it'll end up in the Mustang. You know it will.
 
i dont know if you would call the 2valve "not taking advantage of the ohc" it has its place.....in naturally aspirated form the 2 valve has more low end torque and reaches peak hp/tq before the 4valve motor does...torque levels are VERY similar
 
tjm73 said:
I know. And I think you are right. I think Ford really wanted to try to move themselves up-market and sell themselves as a technologicly advanced company. Make them into a real forward thinking, energetic company. Well, that's the tail end of the Nasser era. one that will go down as one of the worst in Ford's overall history. He ignored cars, and it's gonna take at least decade to fix. I believe it's under his leadership that they nearly killed off the Mustang (remember the Probe situation folks) and it's under his watch that the 4.6 was given the green light over the 5.0. And I'll bet that their was another plan that basically redesigned the 5.0. The 5.0 was it's peak of popularity and had mad street cred and it got killed for a smaller engine. Can some one say mega F-up?

As proof of this, it's widely rumored that Ford is developing a new pushrod engine. They say it's for trucks because trucks need low end torque and the SOHC/DOHC can't deliver the goods for some reason. But if it's smaller, lighter, makes as much or more power and it's cheaper to build, while being environmentally clean, it'll end up in the Mustang. You know it will.
do u have any documentation on this "new pushrod motor"?
 
Modular2v said:
do u have any documentation on this "new pushrod motor"?


I read it at www.thecarconnection.com a few months back. And it is the truth. Ford needs a motor to compete with the Chrysler Hemi and the GM LS2. The powertrain folks at Ford commonly refer to the Chrylser V-8 as the 'HEMROID' becuase their 4.6 / 5.4 can't compete! This might have been in a couple ragazines recently also, but I can't remember.
 
Modular 2V - Good Job:nice:

the 99+'s with the "horrible" 4.6L wipe the mat of a stock 5.0L. 96-98 was a drivers race with a sn95 5.0L.

There is a reason why they didn't come with 4v's. Not everyone needs a 7k revving machine. Not everyone can afford the extra price tag. There has got to be a difference between the gt and cobra right? (2v vs. 4v).
 
Modular2v said:
do u have any documentation on this "new pushrod motor"?

I tried to get onto Blue Oval News (one of the couple places I read about it), but the site was not coming up. I'll try again.

Nope. Still down.

I found this.... Looks like it's been shelved. Bummer.


Ford halts work on engine

Development costs shelve V-8 intended to compete with high-output rivals.

By Eric Mayne / The Detroit News

Ford Motor Co. has halted development of a new, high-output V-8 engine designed to boost the performance of future F-150 pickup models and challenge the popularity of DaimlerChrysler AG's acclaimed Hemi.

The program was suspended because of high development costs, according to Ford officials.

Code-named Hurricane, the 6.2-liter engine was seen as Ford's response to the 5.7-liter Hemi, which has attracted a cult-like following among consumers. A larger 425-horsepower 6.1-liter version of the Hemi will debut this year on the Chrysler 300C SRT8 sedan and Dodge Magnum SRT8 wagon.

While consumer demand for horsepower remains strong, Ford has come under repeated attack from environmentalists for placing at or near the bottom of the industry's fuel economy rankings.

For years, the automaker's average fleet fuel economy has been lower than competitors, spawning anti-Ford campaigns such as Jumpstart Ford, which urges the automaker to adopt advanced fuel efficiency technologies more quickly.

Ford is not abandoning the profitable high-output or high-performance engine market, however. And the automaker's racing arm continues to research and develop new engines.

On Sunday, Ford Racing recorded a 1-2 finish at the opening event of the 2005 Grand-Am Cup season at Daytona with a pair of Mustangs powered by 5.0-liter V-8 engines that debuted at the 2004 New York Auto Show in the Mustang GT-R concept car.

"The 5.0-liter Cammer engine family represents the future of Ford Racing Performance Parts," said Dan Davis, director of Ford Racing Technology.

Ford is also developing an all-aluminum 6.4-liter V-10 engine that produces 605 horsepower. Featured in the Shelby GR-1 concept car that debuted at the Detroit Auto Show, it's lighter than the 550-horsepower supercharged V-8 engine that powers the 2005 Ford GT.