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ford f350 vs. chevy silverado 3500

24

Comments

  • kg11kg11 Posts: 530
    Just kidding.I don't know what I'm going to do.Nothing else on the market matches the power and comfort of GM,and I NEED an A/T cuz my left leg don't work too good.I'm too old to build my own again.Maybe F250 v10.Id feel silly driving a freightliner with 7000 lb behind it.Maybe sell the big boat and just buy a ticket on a party boat when I want to go fishing.I don't want to think about it right now.
    kip
    BTW my friends at whipple superchargers here in Fresno are working on a kit for Ford's v10 but it isn't smog certified yet and I don't know about Ford's A/T
  • hunter98hunter98 Posts: 273
    I am tired of this Tundra is King Debate.

    Put 10,000 or 16000 lbs behind the tundra, and then behind my Duramax going down a hill without trailer brakes. Comparing apples to oranges isn't the point, and all three of the new style Sierra trucks I have had the privilege of owning would flat haul or flat shut down, with or without a trailer.

    3/4 ton truck brakes are designed for durability, resistance to brake fade, heat disapation, and ability to stop heavy loads. Also, a heavier built, stiffer suspensioned truck handles a trailer better.

    I love my Duramax, averaging 17.5 mpg on winter fuel driving hard. Got 12 MPG running 65-70 with 12000 lbs in tow. Can run 55-? in OD towing without any problems. Will outrun and outtow any STOCK Ford or Dodge. And has a transmission designed to hold up to the power and torque of a Diesel. I have friends who have installed multiple transmissions behind their Cummins or Powerstoke. But both are excellent engines.

    Toyota aint even in the game, or in the same class, so don't try and compare again to a 1500HD, 2500, 2500HD or 3500.

    Hunter
  • a 4.8 Silverado or 4.6 F-150 wouldn't be in the same game or class as those trucks you mentioned. Like it or not, the Tundra is competitive when you compare apples to apples. Only a moron would compare a 4.8 Silverado, 4.6 F-150 or a 4.7 Tundra to a 1500HD, 2500, 2500HD or 3500.

    But if it makes you feel better comparing oranges to apples so you can have the advantage, more power to you. I always thought those Chevy Duramax/Allisons were awfully weak compared to those Freightliners...
  • modvptnlmodvptnl Posts: 1,352
    Pluto you are burying yourself.

    Your orginal statement, "I don't recall modelfarm's question so I can't comment" is/was ignorant. This WHOLE topic is about that question.

    Your incredible/important braking performance statements have NOTHING to do with this topic. You have not once shown ANY braking performance quotes for a 2500HD or 3500. You can't compare an Allison equipped or a 6 speed manual equipped vehicle to other vehicles that aren't so equipped. I'm sure you know the manual will assist in braking and the Allison also has a feature to do so.

    Get off your high horse and stop justifying your ignorant braking comments that have nothing to do with the trucks being compared here.

    We all understand your disdain for the 1/2 ton GM's and even if a 1500HD shares rotor size with a 3500, there are other factors that influence the braking performance.

    You can't use info gleaned from 1500's, HD or not, and use it as factual info for a 3500.

    You're wrong, now get over it.
  • The Silverado's brake problems were due in part to a faulty ABS system and had nothing to do with shared rotor sizes (if they are shared). It is a well known and documented fact that GMC ABS brakes IN GENERAL (meaning a broad spectrum of GMC vehicles are affected) have their share of problems, and it is entirely possible the 3500 model series suffer from "premature ABS activation" as well. Given GMC's propensity to employ "parts bin technology" it is highly likely the 3500 series trucks use the same ABS modules/sensors/electronics as do the 1500 series whose braking problems are well documented. The brake "hardware" may or may not differ between the trucks as you stated earlier; however, the hardware isn't the problem, the "software" is so your point is irrelevant. When these facts are taken into consideration, one cannot automatically preclude the 3500 series from suffering from ABS braking problems simply because Edmunds' review of their Sierra does not address this issue or because the trucks in question may or may not share common brake hardware.

    I can't help to think the reason your panties are all bunched up over this is because a Toyota fan brought this fact to light. The title of this thread implies that pros and cons of the F-350 and Silverado 3500 be discussed so that a potential buyer (in this case, the original poster "modelfarm") may make an informed decision.

    Why don't you contribute something informative to this discussion instead of throwing your temper tantrums?
  • Let's see...you say you know problems are due to faulty ABS, but then you don't know if the rotor sizes are shared. Then you speculate the 3500 suffers premature ABS activation. Premature ejaculation of the mouth more likely!
  • I know this is confusing for you, but how would different rotor sizes fix a braking problem when the problem is caused by a faulty ABS system?

    Oh, and the last time I checked, English is spoken in the United States, not Spanish. Though I must say I'm impressed! It also sounds like you know more about premature ejaculation that me...well, at least you're knowledgeable in SOMETHING...
  • modvptnlmodvptnl Posts: 1,352
    Gee Quad, your explanation couldn't be any more simple.

    Let's see, earlier toy pick ups rusted out.....Therefore, I speculate all toys may rust. Some v6' toys blow head gaskets.......Therefore, I speculate it is a problem on all toys. There is a current sludge problem on some toy motors......Therefore, I speculate all toys are prone to this.

    I get it Uranus.....er I mean pluto. GREAT LOGIC.

    Your reading skills must be fading. I did contribute back at post 2....Oh, I forgot, you selectively choose what to read/understand.
  • modvptnlmodvptnl Posts: 1,352
    Your lack of mechanical knowledge will never cease to amaze me.

    Even if the EXACT same ABS "software" is used on the 3500 as the 1500. The weight difference, tire size and a myriad of other factors could/would affect the ABS performance. Please stop, like the combo LSD/locker, you're embarrassing yourself.
  • 2000 Chevrolet S10, Silverado, GMC Sonoma and Sierra Trucks Recalled

    Washington, DC (SafetyAlerts) - The National Highway Traffic Safety Administration has published the recall of certain 2000 Chevrolet S10, Silverado, GMC Sonoma and Sierra trucks, manufactured in August 1999, because certain light duty trucks equipped with 4-wheel disc brakes, the Antilock Brake System (ABS) motor contains an out-of-specification spring clip.


    This clip could allow the motor bearing to become misaligned. If misalignment occurs, eventually the ABS would be non-functional. The base brakes would remain fully functional, but the Dynamic Rear Proportioning (DRP) system, which optimizes front to rear brake balance, would become inoperative, increasing the likelihood of a crash.


    This came from:


     http://www.safetyalerts.com/recall/autorecall/00/055.htm

    --------------------------------------------------


    I'm not posting this to say the spring clip is the culprit for the Sierra's braking problems. The whole point is these vehicles share common ABS system componets and when there's a problem, many models may be affected.


    This supports my statements. I'll wait while you remove your foot from your mouth.

  • I seem to recall a discussion we had regarding pushrod/OHV, SOHC and DOHC engines. You stated that DOHC technology is basically worthless in a pick-up without having variable valve timing and that the engine wouldn't produce any power in the lower RPM range.

    You never commented on how the Toyota DOHC 4.7 creates more torque at a lower RPM than the OHV Chevy 4.8 or SOHC Ford 4.6.

    Again, lack or comprehension and reading skills?
  • modvptnlmodvptnl Posts: 1,352
    There were NO HD2500's or the new 3500's that are part of this discussion for the 2000 model year....This is too easy.
  • modvptnlmodvptnl Posts: 1,352
    You'll never learn.

    I will try to educate you one last time. A DOHC 4 valve motor is, by design, a high revving(7000 RPM+) motor. If it is indeed spinning those high RPM's to create high HP numbers, the low speed drivability will suffer. Hence, most high RPM, high HP 4 valve motors have some sort of variable valve or varible intake technology for respectable low end power.

    The Toy 4.7 is not a high revving, high HP motor. It has respectable numbers, obviously, but no where near what it is capable of or what would be useable in a truck.(what's funny is both the 4.8 GM and 4.6 Ford Mustang have higher HP #'s, another indication the DOHC is not being utilized to its one MAIN advantage) Therefore, The DOHC 4 valve technology is not being utilized well in a 1/2 ton pick up. Basically what I've stated before. Impaired indeed!!!

    Are you sure you're not from Alaska???
  • bamatundrabamatundra Posts: 1,583
    "I'm sure you know the manual will assist in braking and the Allison also has a feature to do so."

    So what are you going to do in a panic stop? Compression brake? Downshift? LMFAO!!!

    Since the 1500HD has exactly the same wimpy brakes as the 2500 and 3500 LDs the brakes are pertinent to this discussion.

    When you load 1000lb in Chev's so-called "HD"s you are driving a very dangerous vehicle. Putting a heavier engine and transmission in it will just make matters worse.

    While on paper you can haul or tow more than 1000lb with Chevs wimpy trucks, you would have to have a death wish to do so.

    It is ironic that a Tundra is actually more capable than Chevs HDs.

    If you want a 3/4 or 1 ton truck that you can work safely - Fords and Dodges are the only game in town right now. Maybe Chev will eventually put some brakes on their trucks??
  • modvptnlmodvptnl Posts: 1,352
    I looked up the specs and found rotor sizes to be the same. Found no info on calipers. You or your side kick have posted no info on braking performance of the 2500HD or 3500. If it really matters to you, A chevy 3500 dually stopped in 139' from 60 compared to 134' from a Ford dually and 132' from a dodge. Hardly a worthwhile difference. The same TRUCK TREND article stated they had "multi piston" calipers on most of the wheels. Too vague for me to comment on.

    Any info for a 1500HD means nothing when comparing a 2500HD or 3500 until you prove the calipers and other components are the same. (Just like your demand of proof of forged pistons, you can't have it both ways)

    Like I TRIED explaining before, saying the brakes are exact just because they are GM would be the same logic that ALL toys rust, blow head gaskets or have sludge.
  • tbundertbunder Posts: 580
    what are you guys, 2 y.o.?

    bama- to even speak of a tundra in an article relating to super-duty, hd chevy's, and ram 3500's is ludicrous. the tundra is more at home in a ranger/tacoma/s10 forum. it barely beats the ranger in gvwr ratings, and it needs helper springs to tow claimed ratings. any of these three real full-size trucks would rip it in half if hooked to one another.

    pluto- you truly need to get a life. do you ACTUALLY think that the 1500hd comes out of the factory with the same exact brakes as a 3500hd truck? do you have a life outside of edmunds? seems every thread i check out, you're right there in the middle stirring trouble. do you realize how retarded you sound to these cowboys who know what the term "truck" means? you know, the guys that see a toyota truck and only see a camry with larger wheels? go call your mom for christs sakes.
  • jaijayjaijay Posts: 162
    Lets see, load up the Tundra with a 1000 pound capacity, make a few panic stops from highway speed, see how how fast those rotors warp!

    Now back to the topic.
  • v12powerv12power Posts: 174
    We sure are making a big deal over the Chevys brakes. These are trucks, they do not stop like cars. I have not had any complaints on my 2500HDs braking. It is almost always hooked to an 8000lb trailer(empty).Loaded or unloaded I have never experienced any braking problems with the Chev, and I have a nearly identical spec Ford F350 around for comparison. I also have a Porsche I race and big beautiful Mercedes sedan, both use world famous Brembo braking systems, I know what good brakes are. My experience with the Chev and Ford is that there is no significant difference. Certainly not enough to justify the craziness here.
  • jaijayjaijay Posts: 162
    I agree. I have never had a problem or any doubt of the stopping capability of my brakes either. This goes for empty or under full tow with my 5th wheel trailer. Granted the trailer has electric brakes, there are often situations that the truck brakes kick in and grab long before the trailer brakes kick in.
  • jcmdiejcmdie Posts: 595
    This topic HAD an interesting title and subject. That was before some posters turned it into another Tundra vs. Chevy topic. I would appreciate those that feel an irresistable urge to argue about the Tundra to MOVE TO AN APPROPRIATE TOPIC.
  • Point #1:

    Chevy ABS brakes are known to be problematic. Many different Chevy vehicles use common ABS parts. I supported links as proof. A potential buyer should take this into consideration. These facts pertain to the topic being discussed.

    Point #2:

    I'm enjoying watching you fall on your own sword with this whole DOHC thing. Did you know other large V8 vehicles are now using DOHC as well, and not just the Tundra? I believe the Lincoln Navigator is one of them. Now why would that be? And who cares about horsepower when we talk about trucks? Torque, especially at low RPMs, is what matters, and the Toy DOHC 4.7 beats the Ford and Chevy in that respect. Typically, high-revving DOHC motors WITH variable valve timing technology produce lots of HP simply because they spin so fast, but very little usable torque. The Tundra is the exact opposite: More torque than horsepower at a low RPM.

    The Toyota DOHC 4.7 contradicts everything you say about these engines. As far as it not being used to its potential in a truck, well, it's obviously being used more to its potential than the Ford 4.6 and Chevy 4.8 because it outperforms them by such a large margin everybody wants to compare the Ford 5.4 or Chevy 5.3 to it.

    I think you're confused on the difference of DOHC/4 valve and variable valve timing. Basically, everything you said about high-revving engines perfectly explains variable valve timing and not necessarily DOHC/4 valve. When an engine starts to spin fast, the time interval in which the intake and exhaust valves are open decrease and the engine can't breath (meaning take in enough fuel and expel the exhaust fast enough). Variable valve timing increases these time intervals (in fact, when increased, they will actually overlap with eachother) at high RPMs so the engine continues to breath.

    While variable valve timing may not be used to its potential in a truck because that's what allows an engine to spin faster, what has that to do with DOHC/4 valve? You most certainly can have DOHC/4 valves without variable valve timing. And just because an engine has DOHC doesn't mean it's going to spin fast and produce no torque. Case in point: Toyota 4.7 V8.

    What you should have been saying all along is "variable valve timing can't be used to its potential in a truck."

    --------------------------------------------------

    End of discussion. This has nothing to do with the topic anymore.
  • modvptnlmodvptnl Posts: 1,352
    You're soooo transparent, it's making you look silly.

    You get stomped on the brake issue (no pun intended) so you bring up a debate that you conceded to months ago.

    Again, you have the mechanics so far out of whack, it's hilarious. VVT or variable intakes are for one thing only: That is to limit the lift/duration of the valves at LOWER engine speeds. Usually around 3000 RPM all variable parameters are off and the engine is breathing with its compliment of full lift. PERIOD.

    The Lincoln DOHC proves my point without a doubt. Ford wanted more (HP 300 vs 260) out of the 5.4 so they slapped the 4 valve heads on(which do use a variable intake track BTW) Take a look, the torque stayed within 5 pounds. This is a perfect example of what 4 valve heads are utilized for, thanks.

    Toy, for good reason, tuned the 4.7 for low end and gave up the one main advantage of 4 valve technology, high end HP. The HP numbers of the 4.7 are pitiful when compared to DOHC/4 valve motors of the same size and even some push rod motors.

    Again, the DOHC/4valve technology is a waste on a pick up truck.
  • PF_FlyerPF_Flyer Pennsylvania Furnace, PAPosts: 5,860
    ...and let's STOP these personal disputes here. Honestly, it doesn't matter that you look like you're arguing about trucks. It's the same people going after each other over the same things over and over...


    If you have a beef with someone that you don't want to let go, take it up with them in their email. Don't fight it out in Town Hall.




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  • GMC is known to have faulty ABS systems. GMC is known to to utilize same ABS componets throughout its different trucks. This is a valid point.

    "Again, you have the mecahnaics so far out of whack, it's hilarious. VVT or vatible intakes are for one thing only: That is to limit the lift/duration of the valves at LOWER engine speeds. Usually around 3000 RPM all varible parameters are off and the engine is breathing with its compliment of full lift. PERIOD"

    Now this is where you're really making yourself look uninformed. VARIABLE VALVE TIMING ADJUSTS VALVE TIMING AS THE ENGINE SPEEDS UP! Look at the older Honda 2 stage variable valve timing engines. From idle to about 4000rpms a unique cam is utilized to open and close the valves and the engine runs "normal." But at rpms greater than 4000, the engine can't breath. Therefore, a SECOND cam with a different shape/profile which actuates the valves kicks in and alters their timing so the engine can breath at high rpms.

    This is an example of a 2 stage variable valve timing design. There are also 3 stage variable valve timing designs which have 3 different cams which kick in as the rpms rise, allowing the engine to breath.

    And it doesn't stop there. The disadvantage with multi-stage variable valve timing designs is that they can't produce power smoothly across the RPM range. You have to reach a certain RPM before the next cam kicks in and then the engine takes off like a rocket - which perfectly describes the Honda engines. Obviously, the more stages and different cams you have, the smoother the power will become but at the expense of added complexity.

    Now they even have continously variable valve timing technology which eliminates the nonuniform power distribution/transition problems the multi-stage designs suffer from. And, many engines are now using variable valve timing on both the intake AND exhaust valves. And if that weren't enough, variable valve lift is also being used to optimize performance.

    But the whole point of this is the valve timing is altered as the RPMs rise so that the engine can still breath. And according to you, the Toyota 4.7 doesn't even utilize variable valve timing and why should it? It's not designed to high-rev.

    "the HP numbers of the 4.7 are pitiful when compared to DOHC/4 valve motors of the same size and even some push rod motors."

    Duh - the 4.7 is tuned for torque at low rpms, not high revving horse power. And it beats the Ford 4.6 and Chevy 4.8.

    You know, if you're going to say DOHC technology is a waste on a truck without having variable valve timing, why not say the same for SOHC engines like the Ford? SOHC engines could certainly benefit from variable valve timing as well.

    NO MATTER WHAT YOU MAY SAY ABOUT DOHC TECHNOLOGY ON A TRUCK, IT DOESN'T CHANGE THE FACT THAT THE TOYOTA DOHC 4.7 OUTPERFORMS THE FORD SOHC 4.6 AND CHEVY OHV 4.8.
    ----------------------------------------------------------------------

    Pf-flyer's right. This doesn't belong here. If you want to discuss this further, let's start our own thread.
  • modvptnlmodvptnl Posts: 1,352
    The GM 4.8 has more HP. The Ford 4.6 in the Mustang has more HP. The SOHC Fords are 2 valve(don't need VVT, besides the 4 valve Fords have variable intakes which restricts the air at lower RPM, JUST LIKE VVT)

    VVT increases low speed torque. The VVT is the exact opposite as you've explained. It limits the air at lower RPM to increase port velocity. Why can't you understand this. OHC 4 valve motors allow an engine to breathe too MUCH.(not being utilized in the toy) There has to be something in place to keep low speed port velocity up. Too much air at lower port velocities hurts low speed performance/torque. 4 valve heads by nature will allow more air. I can't make it any more simple. BTW, VVT has no extra "cams" some use variable lobes or extra lobes that are activated hydraulicly(sp?) or mechanically. there are no Honda's with 3 different cams. LOL!!! Infact the VVT in the V6 Hondas use 1 cam(SOHC) per bank and stilluse 4 valves.

    Ok, all Gm trucks have faulty ABS. By this logic all toys rust and blow headgaskets and warp their front rotors.

    PF, the engine technology stuff may be off this particular topic but I'm sincere in saying that I'm honestly trying to make a point. There is nothing personal.
  • about the cam lobes, not cams. My bad, it was a word mix-up. But that doesn't change the fact VVT increases the engines ability to breath at high RPMs.

    I still don't see why you're arguing about horsepower instead of torque when we're talking about trucks. The Tundra may have a lower hp rating than the F-150 4.6 and Silverado 4.8, but it has more torque. It will also out-accelerate both of these trucks.

    "VVT increases low speed torque. The VVT is the exact opposite as you've explained. It limits the air at lower RPM to increase port velocity. Why can't you understand this. OHC 4 valve motors allow an engine to breathe too MUCH.(not being utilized in the toy) There has to be something in place to keep low speed port velocity up. Too much air at lower port velocities hurts low speed performance/torque."

    Then how is the DOHC 4 valve Toyota 4.7 MAKING MORE TORQUE AT A LOWER RPM THAN THE FORD 4.6 OR CHEVY 4.8??????????????????????????????????

    Go do a search on autozine technical school. This website explains in detail what VVT is all about and it COMPLETELY CONTRADICTS your statements on VVT.

    While I do agree that much of this technology is put to waste on a truck, you have to consider which type of truck we're talking about. There are advantages to this technology to an engine of less than 5 litres being used to tow less than 8000lbs. Big trucks, that's a different story.
  • modvptnlmodvptnl Posts: 1,352
    The HP vs torque is EXACTLY my point. A 4 valve head should have an advantage at higher engine speeds to produce more HP. Toy does not use it for that. They choose to tune a high performance 4 valve head to run higher torque at lower RPM.

    This is what I've said from the beginning of time. Why waste high RPM high horsepower 4 valve technology to produce a torque motor?
  • modvptnlmodvptnl Posts: 1,352
    Your last paragraph of your edited post is exactly how you left it last time. That is all i've been trying to say.
  • This explains in depth what variable valve timing is all about:


    http://autozine.kyul.net/technical_school/engine/vvt_1.htm


    This is the best part of the article:

    As you know, valves activate the breathing of engine. The timing of breathing, that is, the timing of air intake and exhaust, is controlled by the shape and phase angle of cams. To optimise the breathing, engine requires different valve timing at different speed. When the rev increases, the duration of intake and exhaust stroke decreases so that fresh air becomes not fast enough to enter the combustion chamber, while the exhaust becomes not fast enough to leave the combustion chamber. Therefore, the best solution is to open the inlet valves earlier and close the exhaust valves later. In other words, the Overlapping between intake period and exhaust period should be increased as rev increases.

    With Variable Valve Timing, power and torque can be optimised across a wide rpm band. The most noticeable results are:


    The engine can rev higher, thus raises peak power. For example, Nissan's 2-litre Neo VVL engine output 25% more peak power than its non-VVT version.
    Low-speed torque increases, thus improves drivability. For example, Fiat Barchetta's 1.8 VVT engine provides 90% peak torque between 2,000 and 6,000 rpm.

    Moreover, all these benefits come without any drawback.
    ----------------------------------------------------------------------
    This explains 4 valve engines. This should be of particular interest to you because it explains how Toyota solved some of the low-rpm problems associated with such engines.


    http://autozine.kyul.net/technical_school/engine/tech_engine_2.htm#Multi-valve

    This was the best part of the article:

    Most early 4-valve engines were not good at low-to-middle speed torque, simply because the larger intake area resulted in slower air flow. Especially at low speed, the slow air flow in the intake manifold led to imperfect mixing of fuel and air, hence knocking and reduced power and torque. Therefore 4-valve engines were regarded as strong at top end but weak at the bottom end, until the technology of variable intake manifold became popular recently. The aforementioned Chevrolet Cosworth Vega performed particularly weak at low speed.

    In response to this, Toyota introduced T-VIS (Toyota Variable Intake System) in the mid-80s. T-VIS accelerated low speed air flow to the manifold. The theory was quite simple: the intake manifold for each cylinder was split into two separate sub-manifold which joint together near the intake valves. A butterfly valve was added at one of the sub-manifold. At below 4,650 rpm the butterfly valve would be closed so that raising the velocity of air in the manifold. As a result, better mixing could be obtained at the manifold (excluding direct-injection engines, fuel injection always takes place in the manifold).

    However, for later mainstream sedan engines, Toyota dropped this idea and adopted a small-diameter intake manifold / port design. Many other car makers also went the same way, sacrificing a bit top end power to improve low speed flexibility. Today, the introduction of variable intake manifold can solve this problem.
    ----------------------------------------------------------------------

  • This is what you said about my understanding of VVT and also your explanation of what it does:

    "Again, you have the mechanics so far out of whack, it's hilarious. VVT or variable intakes are for one thing only: That is to limit the lift/duration of the valves at LOWER engine speeds. Usually around 3000 RPM all variable parameters are off and the engine is breathing with its compliment of full lift. PERIOD"

    With all due respect, but "whose mechanics are so far out of whack it's hilarious?" Just as a I stated earlier, VVT certainly IS what allows and engine to spin faster by allowing it to breath at high rpms. VVT doesn't just "limit the lift/duration of the valves at LOWER engine speeds...PERIOD" as you stated. Rather, it "opens the inlet valves earlier and close the exhaust valves later. In other words, the Overlapping between intake period and exhaust period should be increased as rev increases. With Variable Valve Timing, power and torque can be optimised across a wide rpm band. The most noticeable results are: The engine can rev higher, thus raises peak power."
    --------------------------------------------------

    Here's what you said about DOHC/4 valve engines:

    "The VVT is the exact opposite as you've explained. It limits the air at lower RPM to increase port velocity. Why can't you understand this. OHC 4 valve motors allow an engine to breathe too MUCH.(not being utilized in the toy) There has to be something in place to keep low speed port velocity up. Too much air at lower port velocities hurts low speed performance/torque."

    What? How does VVT "limit the air at lower RPM to increase port velocity. Why can't you understand this." No, VVT doesn't do that, a variable intake manifold does. All a variable intake manifold does is restrict the size of the column of air, therefore speeding it up.

    Your impressions of DOHC/4 valve engines are based on older designs which probably did not benefit from things like variable intake manifolds. Furthermore, the biggest problem that DOHC/4 valve engines had with their slow-moving air in intake manifold was poor fuel/air mixing. And as the article stated, this problem was alleviated when fuel injection was introduced. And the last time I checked, there's no carburetor on the Toyota DOHC 4.7. And this engine still produced more torque at lower RPMs than the SOHC Ford 4.6 or OHV Chevy 4.8 (both of which aren't 4 valve engines, obviously).
This discussion has been closed.