Hemi Challenger

On Tue, 02 Oct 2007 20:39:11 GMT, "My Name Is Nobody" >
wrote:

>
>"Joe" > wrote in message
. ..
>> trainfan1 > wrote in
>> et:
>>
>>> Joe wrote:
>>>
>>>>
>>>> OK, here are some specs taken from each maker's web site:
>>>>
>>>> Ford 4.6L SOHC 3V
>>>> HP - 300 @ 5750
>>>> TQ - 320 @ 4500
>>>>
>>>> Ford 5.4L SOHC 3V
>>>> HP - 300 @ 5000 rpm
>>>> TQ - 365 @ 3750 rpm
>>>>
>>>> Dodge 4.7L SOHC (2008)
>>>> HP - 302 @ 5650 rpm
>>>> TQ - 329 @ 3950 rpm
>>>>
>>>> Dodge 5.7L OHV
>>>> HP - 335 @ 5000 rpm
>>>> TQ - 375 @ 4000 rpm
>>>>
>>>> Dodge 6.1L OHV
>>>> HP - 425 @ 6000 rpm
>>>> TQ - 420 @ 4800 rpm
>>>>
>>>> Chevy 4.8L Vortec OHV
>>>> HP - 295 @ 5600 rpm
>>>> TQ - 305 @ 4800 rpm
>>>>
>>>> Chevy 5.3L Vortec OHV
>>>> HP - 315 @ 5200 rpm
>>>> TQ - 338 @ 4400 rpm
>>>>
>>>> Chevy 6.0L Vortec MAX OHV
>>>> HP - 367 @ 5500 rpm
>>>> TQ - 375 @ 4300 rpm
>>>>
>>>> Chevy 6.0L LS2 OHV
>>>> HP - 400 @ 6000 rpm
>>>> TQ - 400 @ 4400 rpm
>>>>
>>>> Chevy 7.0L LS7 OHV
>>>> HP - 505 @ 6300 rpm
>>>> TQ - 470 @ 4800 rpm
>>>>
>>>> Interesting numbers, to say the least. If anything pops out, it's
>> that
>>>> Ford doesn't have a n/a motor over 300hp.
>>>
>>> Ford 6.8L SOHC 3V(2005 & up)
>>> HP - 362 @ 4750 RPM
>>> TQ - 457 @ 3250 RPM
>>>
>>> Rob
>>
>> That's a V10. I should've specified V8s...
>
>Why? Why not specify over head cam while you are at it?
>Then you could say Chevy and Chrysler don't have a naturally aspirated OHC
>engine that makes over 250 horsepower...
>Hum this is getting silly..
>
>BTW:
>The Ford 6.8 naturally aspirated OHC engine is a truck engine, and makes
>comparable power to the other's OHV performance car engines...
>

So, Chrysler's 413 was a truck engine. So was Ford's 460, and GM's 396
and 427.(and the venerable 409 too)
Didn't make them any less of a good car engine


--
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On Tue, 02 Oct 2007 12:04:18 -0400, Michael Johnson >
wrote:

>clare at snyder.on.ca wrote:
>> On Mon, 01 Oct 2007 22:30:32 -0400, Michael Johnson >
>> wrote:
>>
>>
>>> The Mustang's 4.6L is Ford's only N/A high performance engine at the
>>> moment. The after market tuners are getting another 30-40 hp from them
>>> with tuning tweaks and these cars still pass all the emissions tests.
>>> Ford could do the same from the factory but don't need to because the
>>> car has no immediate competition. Getting 340 hp from 4.6 liters is
>>> better hp/liter numbers than the Z06 of Viper engines. Ford could
>>> easily give the 4.6L another 1000 rpm up top and push it to 400 hp, IMO.
>>> Heck, nearly 17-18 years ago Ford was offering an OHC SHO engine in
>>> the Taurus that made better hp/liter numbers than today's Z06 or Viper
>>> OHV engines.
>>
>> It wasn't a Ford engine, though. It was a Yamaha.
>> And the Duratec V6 isn't a "Ford" engine either. Yes, they build it,
>> but the block is a Porsche design, and the heads are Cosworth. ANd it
>> is a royal pain to work on, and DOES require more work than lower
>> output pushrod engines.
>
>I know the SHO V-6 is a Yamaha engine but we are really comparing OHC to
>OHV for discussion purposes of hp/liter output and basic design
>superiority. BTW, removing a cam from an OHV engine isn't a piece of
>cake either as is the lifters. Been there and done that. I do think
>OHC engines have more packaging issues than OHV due to their increased size.

Just because an engine is OHC doesn't make it easier to remove the
cam. Anyone who's replaced the cam on a BMW 2002 Tii will vouch for
that. I have changed the cam in a Chevy V8 in under 3 hours with no
power tools. In a Chevy 230 six in less than 2 hours.
The 2002 took over 4.
Also, when the cam goes in the AVERAGE OHC engine, the head can be
junk as there are generally no cam bearings. MANY OHC engines are
basically throw-away when they go bad as they are not feasible to
rebuild. MOST OHV (cam in block) engines are very rebuildable. (and
economically, too)

That said, Ford really screwed up with the 3.8!!!

--
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On Tue, 02 Oct 2007 20:46:20 GMT, "My Name Is Nobody" >
wrote:

>
><clare at snyder.on.ca> wrote in message
.. .
>> On Mon, 01 Oct 2007 22:30:32 -0400, Michael Johnson >
>> wrote:
>>
>>
>>>
>>>The Mustang's 4.6L is Ford's only N/A high performance engine at the
>>>moment. The after market tuners are getting another 30-40 hp from them
>>>with tuning tweaks and these cars still pass all the emissions tests.
>>>Ford could do the same from the factory but don't need to because the
>>>car has no immediate competition. Getting 340 hp from 4.6 liters is
>>>better hp/liter numbers than the Z06 of Viper engines. Ford could
>>>easily give the 4.6L another 1000 rpm up top and push it to 400 hp, IMO.
>>> Heck, nearly 17-18 years ago Ford was offering an OHC SHO engine in
>>>the Taurus that made better hp/liter numbers than today's Z06 or Viper
>>>OHV engines.
>>
>> It wasn't a Ford engine, though. It was a Yamaha.
>
>So is the so called "Hemi" built in Mexico actually a Chrysler engine?
Yes, designed and built by Chrysler in their own facility. Just
happens to be in Mexico. However, it is NOT really a "HEMI".
>Is the Isuzu built diesel actually a Chevy Duramax engine?
Yes in as far as GM "OWNS" Isuzu
>Is the International diesel actually a Ford Power Stroke engine?
No, the Ford PowerStroke engine is an International engine. Built for
Ford by International - a modified version of the International
(Navistar) "S" Series.
>
>In this day and age that is a really silly distinction. Almost all cars
>have outsourced parts...

Agreed - we are returning to the day of the "assembled" car rather
than the manufactured car.
The Model "T" Ford was actually manufactured, almost entirely, by the
Dodge Brothers in it's early years - and "assembled" by Ford.

Many "manufacturers" of cars and trucks up to the fifties used engines
made by another company - continental was one. Lycoming (in earlier
years) was another. Chrysler and Willy's engines were used by several
"manufacturers". Even the bodys of many makes were "borrowed". IIRC
Graham used modified Ford bodies.

Much more common in trucks - and VERY prevalent today.
Are Mack and International the only major (heavy) truck companies
still building their own engines (other than the Japanese) in the
American market?
>The Ford SHO KICKED ASS, and was about 15-20 years ahead of it's time...
At least. And it stood up quite well to the "abuse" many drivers
handed it.
>
>> And the Duratec V6 isn't a "Ford" engine either. Yes, they build it,
>> but the block is a Porsche design, and the heads are Cosworth. ANd it
>> is a royal pain to work on, and DOES require more work than lower
>> output pushrod engines.
>>>
>>
>>
>> --
>> Posted via a free Usenet account from http://www.teranews.com
>>
>


--
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<clare at snyder.on.ca> wrote in message
...
> On Tue, 02 Oct 2007 20:39:11 GMT, "My Name Is Nobody" >
> wrote:
>
>>
>>"Joe" > wrote in message
.. .
>>> trainfan1 > wrote in
>>> et:
>>>
>>>> Joe wrote:
>>>>
>>>>>
>>>>> OK, here are some specs taken from each maker's web site:
>>>>>
>>>>> Ford 4.6L SOHC 3V
>>>>> HP - 300 @ 5750
>>>>> TQ - 320 @ 4500
>>>>>
>>>>> Ford 5.4L SOHC 3V
>>>>> HP - 300 @ 5000 rpm
>>>>> TQ - 365 @ 3750 rpm
>>>>>
>>>>> Dodge 4.7L SOHC (2008)
>>>>> HP - 302 @ 5650 rpm
>>>>> TQ - 329 @ 3950 rpm
>>>>>
>>>>> Dodge 5.7L OHV
>>>>> HP - 335 @ 5000 rpm
>>>>> TQ - 375 @ 4000 rpm
>>>>>
>>>>> Dodge 6.1L OHV
>>>>> HP - 425 @ 6000 rpm
>>>>> TQ - 420 @ 4800 rpm
>>>>>
>>>>> Chevy 4.8L Vortec OHV
>>>>> HP - 295 @ 5600 rpm
>>>>> TQ - 305 @ 4800 rpm
>>>>>
>>>>> Chevy 5.3L Vortec OHV
>>>>> HP - 315 @ 5200 rpm
>>>>> TQ - 338 @ 4400 rpm
>>>>>
>>>>> Chevy 6.0L Vortec MAX OHV
>>>>> HP - 367 @ 5500 rpm
>>>>> TQ - 375 @ 4300 rpm
>>>>>
>>>>> Chevy 6.0L LS2 OHV
>>>>> HP - 400 @ 6000 rpm
>>>>> TQ - 400 @ 4400 rpm
>>>>>
>>>>> Chevy 7.0L LS7 OHV
>>>>> HP - 505 @ 6300 rpm
>>>>> TQ - 470 @ 4800 rpm
>>>>>
>>>>> Interesting numbers, to say the least. If anything pops out, it's
>>> that
>>>>> Ford doesn't have a n/a motor over 300hp.
>>>>
>>>> Ford 6.8L SOHC 3V(2005 & up)
>>>> HP - 362 @ 4750 RPM
>>>> TQ - 457 @ 3250 RPM
>>>>
>>>> Rob
>>>
>>> That's a V10. I should've specified V8s...
>>
>>Why? Why not specify over head cam while you are at it?
>>Then you could say Chevy and Chrysler don't have a naturally aspirated OHC
>>engine that makes over 250 horsepower...
>>Hum this is getting silly..
>>
>>BTW:
>>The Ford 6.8 naturally aspirated OHC engine is a truck engine, and makes
>>comparable power to the other's OHV performance car engines...
>>
>
> So, Chrysler's 413 was a truck engine. So was Ford's 460, and GM's 396
> and 427.(and the venerable 409 too)
> Didn't make them any less of a good car engine

Fords 460 was a Lincoln car engine long before it was a truck engine...

>
>
> --
> Posted via a free Usenet account from http://www.teranews.com
>

On Tue, 02 Oct 2007 12:23:17 -0400, Michael Johnson >
wrote:

>clare at snyder.on.ca wrote:
>> On Mon, 01 Oct 2007 23:27:26 -0400, Michael Johnson >
>> wrote:
>>
>>> wrote:
>>>> On Sep 30, 10:48 pm, Michael Johnson > wrote:
>>>>> clare at snyder.on.ca wrote:
>>>>> Try putting a twin screw making 9 lbs. of boost on a bone stock Viper
>>>>> and see what happens. The stock 4.6L will take that 9 lbs. of boost in
>>>>> stride and make 425-450 rwhp or over 500 hp at the crank. Try that same
>>>>> amount of boost on a stock Viper engine and odds are it will have a
>>>>> catastrophic failure due to its high compression ratio.
>>>> Much like many of the older [high-compression] 4.6 Cobras did after
>>>> their owners added blowers.
>>>>
>>>> Again, your comparisons are not very good.
>>> I wasn't talking about the N/A Cobra engines. My comparisons are
>>> between today's Viper and Mustang engines. Ford builds more headroom
>>> into their modular V-8s. Can a Viper engine handle a 50-60% increase in
>>> power output without removing the valve covers or oil pan? I know the
>>> Mustang's OHC engine can.
>>
>> The "blower" mustang starts with lower CR out of the box than the non
>> blower engine.
>
>I'm not even talking about the blown 4.6L from the factory. The Mustang
>GT engine can take 9 psi with little risk if the tune is right. Where
>the Viper and Z06 engines are pushed closer to their limits from the
>factory the 4.6L engine in the Mustang is not and it still makes
>hp/liter numbers on par with the other two engines. If Ford pushed the
>4.6L as far as the Viper and Z06 they would pass those motors in
>hp/liter output, IMO. I know the after market tuners are getting 30-40
>more rwhp from them with tuning alone while maintaining reliability and
>meeting emissions requirements. Imagine what Ford could do with tuning
>the 4.6L in the Mustang if they had the motivation.
>
>The whole point of the discussion here is that, IMO, OHC engines have
>inherent design advantages over OHV engines. The fact that Ford's OHC
>4.6L in the Mustang is matching the Viper and Z06 hp/liter numbers and
>still has enough headroom to handle 9 psi of boost shows the superiority
>of the OHC design, IMO. Ford could easily place four valve heads with
>VVT and raise the redline to 7,500 rpm (the OHC design makes high
>redlines easier to achieve) and get 400+ hp from their 4.6L engine.
>This would be more hp than the LS2 using 1.4 liters less engine
>displacement.

Yes, OHC engines have some advantages. My point is, under NORMAL use
the advantages are negligable. The engines must be wound tight to make
use of most of the advantage - Horsepower alone tells only a small
part of the story. Today's AVERAGE car runs somewhere around 2000 RPM
at legal highway speeds in top gear.
Under NORMAL HIGHWAY DRIVING an engine with dual overhead cams and 4
valves per cyl has little if any advantage over a pushrod 2 valve
engine of the same displacement. It has NO advantage over that pushrod
engine in durability or longevity, all else being equal.
It has a definite DISADVANTAGE when it comes to cost to repair.
It is also at a disadvantage packaging-wise- as it is significantly
larger in virtually all dimensions than a pushrod engine. It is also
generally HEAVIER if made of the same materials.
Yes, many high output OHC engines are lighter than the equivalent OHV
engine, but just because the "low tech" engine elected to stay with
cast iron heads and block instead of the aluminum used by many/most
OHC engines for at least the heads, and most often the blocks.

That said, today's thin cast iron blocks suffer only a small weight
penalty over the average aluminum block of only a few years ago.

So - if you are talking no-holds barred performance engines, and
maintenance/repair costs (as well as production costs) are a secondary
consideration - yes, OHC engines have an advantage.
DOHC has a marge larger advantage over SOHC than SOHC has over OHV
technology when you get into the higher output higher speed engines
because variable cam geometry is so much easier on a dual cam setup.

This does NOT make a pushrod engine necessarily a lesser engine for
some 90+% of owners and drivers.

--
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clare at snyder.on.ca wrote:
> On Tue, 02 Oct 2007 12:04:18 -0400, Michael Johnson >
> wrote:
>
>> clare at snyder.on.ca wrote:
>>> On Mon, 01 Oct 2007 22:30:32 -0400, Michael Johnson >
>>> wrote:
>>>
>>>
>>>> The Mustang's 4.6L is Ford's only N/A high performance engine at the
>>>> moment. The after market tuners are getting another 30-40 hp from them
>>>> with tuning tweaks and these cars still pass all the emissions tests.
>>>> Ford could do the same from the factory but don't need to because the
>>>> car has no immediate competition. Getting 340 hp from 4.6 liters is
>>>> better hp/liter numbers than the Z06 of Viper engines. Ford could
>>>> easily give the 4.6L another 1000 rpm up top and push it to 400 hp, IMO.
>>>> Heck, nearly 17-18 years ago Ford was offering an OHC SHO engine in
>>>> the Taurus that made better hp/liter numbers than today's Z06 or Viper
>>>> OHV engines.
>>> It wasn't a Ford engine, though. It was a Yamaha.
>>> And the Duratec V6 isn't a "Ford" engine either. Yes, they build it,
>>> but the block is a Porsche design, and the heads are Cosworth. ANd it
>>> is a royal pain to work on, and DOES require more work than lower
>>> output pushrod engines.
>> I know the SHO V-6 is a Yamaha engine but we are really comparing OHC to
>> OHV for discussion purposes of hp/liter output and basic design
>> superiority. BTW, removing a cam from an OHV engine isn't a piece of
>> cake either as is the lifters. Been there and done that. I do think
>> OHC engines have more packaging issues than OHV due to their increased size.
>
> Just because an engine is OHC doesn't make it easier to remove the
> cam. Anyone who's replaced the cam on a BMW 2002 Tii will vouch for
> that. I have changed the cam in a Chevy V8 in under 3 hours with no
> power tools. In a Chevy 230 six in less than 2 hours.
> The 2002 took over 4.

Pulling a cam from a transverse mounted OHV engine usually means pulling
the engine. In a longitudinal mount it usually means removing the
radiator at a minimum, or worse. Depends on the car.

> Also, when the cam goes in the AVERAGE OHC engine, the head can be
> junk as there are generally no cam bearings. MANY OHC engines are
> basically throw-away when they go bad as they are not feasible to
> rebuild. MOST OHV (cam in block) engines are very rebuildable. (and
> economically, too)

In today's world most new cars are throw aways no matter what engine
they have. It doesn't make sense to put $4,000+ worth of repairs into a
car that is worth maybe $2,000. One thing I will say about today's cars
is they are much more durable, on average. Getting 100,000 miles from a
car 30-40 years ago was considered good. Now they are just getting
broken in if they are maintained well. Plus, the maintenance regime is
heaven nowadays compared to the good old days of condensers, points,
short lived spark plugs etc. Remember when Ziebart treatment was
necessary to keep vehicles from rusting apart by the time they reached
100,000 miles?

> That said, Ford really screwed up with the 3.8!!!

I wouldn't say they screwed up the engine design as much as they screwed
up the head gasket specifications.

On Tue, 02 Oct 2007 22:28:22 GMT, "My Name Is Nobody" >
wrote:

>
>"Joe" > wrote in message
. ..
>> Michael Johnson > wrote in
>> :
>
>
>
>>>>> The fact that Ford's OHC
>>>>> 4.6L in the Mustang is matching the Viper and Z06 hp/liter numbers
>>>>> and still has enough headroom to handle 9 psi of boost shows the
>>>>> superiority of the OHC design, IMO.
>>>>
>>>> Sorry, Michael, but I can't buy it. I see it as the 4.6 being
>>>> "under- engineered".
>>>
>>> What you call "under engineered" I call untapped potential for making
>>> more power (i.e. headroom).
>>
>> I was sort of being facetious, but at least I was able to make my point.
>>
>>
>>> I think Ford intentionally does this to
>>> give the Mustang buyer the ability to tweak his car to get more
>>> performance for cheap. I think Ford chiseled this in the Mustang's
>>> list of commandments when they conceived it back in the 1960s.
>>
>
>Here in lies the key to the Mustangs phenomenal success, the largest most
>successful "after market parts" industry ever for any car period.
>
You can build a 1966 Mustang totally from parts for significantly less
than you can restore a "decent" Cuda , Challenger, Charger, or
virtually any other Mopar of the period. And Chevy falls in between
somewhere. A Camero or Chevelle is easier / cheaper to rebuild than a
Mopar because there are more parts available, at a significantly lower
cost.

--
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My Name Is Nobody wrote:
> <clare at snyder.on.ca> wrote in message
> ...
>> On Tue, 02 Oct 2007 20:39:11 GMT, "My Name Is Nobody" >
>> wrote:
>>
>>> "Joe" > wrote in message
>>> ...
>>>> trainfan1 > wrote in
>>>> et:
>>>>
>>>>> Joe wrote:
>>>>>
>>>>>> OK, here are some specs taken from each maker's web site:
>>>>>>
>>>>>> Ford 4.6L SOHC 3V
>>>>>> HP - 300 @ 5750
>>>>>> TQ - 320 @ 4500
>>>>>>
>>>>>> Ford 5.4L SOHC 3V
>>>>>> HP - 300 @ 5000 rpm
>>>>>> TQ - 365 @ 3750 rpm
>>>>>>
>>>>>> Dodge 4.7L SOHC (2008)
>>>>>> HP - 302 @ 5650 rpm
>>>>>> TQ - 329 @ 3950 rpm
>>>>>>
>>>>>> Dodge 5.7L OHV
>>>>>> HP - 335 @ 5000 rpm
>>>>>> TQ - 375 @ 4000 rpm
>>>>>>
>>>>>> Dodge 6.1L OHV
>>>>>> HP - 425 @ 6000 rpm
>>>>>> TQ - 420 @ 4800 rpm
>>>>>>
>>>>>> Chevy 4.8L Vortec OHV
>>>>>> HP - 295 @ 5600 rpm
>>>>>> TQ - 305 @ 4800 rpm
>>>>>>
>>>>>> Chevy 5.3L Vortec OHV
>>>>>> HP - 315 @ 5200 rpm
>>>>>> TQ - 338 @ 4400 rpm
>>>>>>
>>>>>> Chevy 6.0L Vortec MAX OHV
>>>>>> HP - 367 @ 5500 rpm
>>>>>> TQ - 375 @ 4300 rpm
>>>>>>
>>>>>> Chevy 6.0L LS2 OHV
>>>>>> HP - 400 @ 6000 rpm
>>>>>> TQ - 400 @ 4400 rpm
>>>>>>
>>>>>> Chevy 7.0L LS7 OHV
>>>>>> HP - 505 @ 6300 rpm
>>>>>> TQ - 470 @ 4800 rpm
>>>>>>
>>>>>> Interesting numbers, to say the least. If anything pops out, it's
>>>> that
>>>>>> Ford doesn't have a n/a motor over 300hp.
>>>>> Ford 6.8L SOHC 3V(2005 & up)
>>>>> HP - 362 @ 4750 RPM
>>>>> TQ - 457 @ 3250 RPM
>>>>>
>>>>> Rob
>>>> That's a V10. I should've specified V8s...
>>> Why? Why not specify over head cam while you are at it?
>>> Then you could say Chevy and Chrysler don't have a naturally aspirated OHC
>>> engine that makes over 250 horsepower...
>>> Hum this is getting silly..
>>>
>>> BTW:
>>> The Ford 6.8 naturally aspirated OHC engine is a truck engine, and makes
>>> comparable power to the other's OHV performance car engines...
>>>
>> So, Chrysler's 413 was a truck engine. So was Ford's 460, and GM's 396
>> and 427.(and the venerable 409 too)
>> Didn't make them any less of a good car engine
>
> Fords 460 was a Lincoln car engine long before it was a truck engine...
>
>>

AND the 413 was a car engine long before it was a truck engine...

Rob

clare at snyder.on.ca wrote:
> On Tue, 02 Oct 2007 12:23:17 -0400, Michael Johnson >
> wrote:
>
>> clare at snyder.on.ca wrote:
>>> On Mon, 01 Oct 2007 23:27:26 -0400, Michael Johnson >
>>> wrote:
>>>
>>>> wrote:
>>>>> On Sep 30, 10:48 pm, Michael Johnson > wrote:
>>>>>> clare at snyder.on.ca wrote:
>>>>>> Try putting a twin screw making 9 lbs. of boost on a bone stock Viper
>>>>>> and see what happens. The stock 4.6L will take that 9 lbs. of boost in
>>>>>> stride and make 425-450 rwhp or over 500 hp at the crank. Try that same
>>>>>> amount of boost on a stock Viper engine and odds are it will have a
>>>>>> catastrophic failure due to its high compression ratio.
>>>>> Much like many of the older [high-compression] 4.6 Cobras did after
>>>>> their owners added blowers.
>>>>>
>>>>> Again, your comparisons are not very good.
>>>> I wasn't talking about the N/A Cobra engines. My comparisons are
>>>> between today's Viper and Mustang engines. Ford builds more headroom
>>>> into their modular V-8s. Can a Viper engine handle a 50-60% increase in
>>>> power output without removing the valve covers or oil pan? I know the
>>>> Mustang's OHC engine can.
>>> The "blower" mustang starts with lower CR out of the box than the non
>>> blower engine.
>> I'm not even talking about the blown 4.6L from the factory. The Mustang
>> GT engine can take 9 psi with little risk if the tune is right. Where
>> the Viper and Z06 engines are pushed closer to their limits from the
>> factory the 4.6L engine in the Mustang is not and it still makes
>> hp/liter numbers on par with the other two engines. If Ford pushed the
>> 4.6L as far as the Viper and Z06 they would pass those motors in
>> hp/liter output, IMO. I know the after market tuners are getting 30-40
>> more rwhp from them with tuning alone while maintaining reliability and
>> meeting emissions requirements. Imagine what Ford could do with tuning
>> the 4.6L in the Mustang if they had the motivation.
>>
>> The whole point of the discussion here is that, IMO, OHC engines have
>> inherent design advantages over OHV engines. The fact that Ford's OHC
>> 4.6L in the Mustang is matching the Viper and Z06 hp/liter numbers and
>> still has enough headroom to handle 9 psi of boost shows the superiority
>> of the OHC design, IMO. Ford could easily place four valve heads with
>> VVT and raise the redline to 7,500 rpm (the OHC design makes high
>> redlines easier to achieve) and get 400+ hp from their 4.6L engine.
>> This would be more hp than the LS2 using 1.4 liters less engine
>> displacement.
>
> Yes, OHC engines have some advantages. My point is, under NORMAL use
> the advantages are negligable. The engines must be wound tight to make
> use of most of the advantage - Horsepower alone tells only a small
> part of the story. Today's AVERAGE car runs somewhere around 2000 RPM
> at legal highway speeds in top gear.

Truth be told we could all get by with three cylinder shoe boxes for
basic transportation. People don't buy high performance car because
they need them.

> Under NORMAL HIGHWAY DRIVING an engine with dual overhead cams and 4
> valves per cyl has little if any advantage over a pushrod 2 valve
> engine of the same displacement. It has NO advantage over that pushrod
> engine in durability or longevity, all else being equal.

I disagree with the above. With VVT, multiple intake and/or exhaust
valves, dual tuned runners etc. the power band can be enhanced from idle
to redline. In the OHV engines I have run to high mileage the bigest
chance of parts failure has rested with the valve train. It can be a
ticking lifter, bent push rod or a bum rocker arm. IMO, these
components are the Achille's heals for OHV engines. They don't exist in
an OHC engine and therefore con not be the cause of failures. The
durability of Ford's 4.6L is legendary already and I chalk a lot of it
up to the OHC design. Fewer reciprocating parts mean greater
reliability and longer life, IMO.

> It has a definite DISADVANTAGE when it comes to cost to repair.
> It is also at a disadvantage packaging-wise- as it is significantly
> larger in virtually all dimensions than a pushrod engine. It is also
> generally HEAVIER if made of the same materials.
> Yes, many high output OHC engines are lighter than the equivalent OHV
> engine, but just because the "low tech" engine elected to stay with
> cast iron heads and block instead of the aluminum used by many/most
> OHC engines for at least the heads, and most often the blocks.

I will give you that OHC heads are more a throw away part the their OHV
counter part. That being said the infrequency of early catastrophic
engine failure in today's engines (OHV and OHC) makes this a minimal
issue. If today's cars are maintained well engine failures are few and
far between.

> That said, today's thin cast iron blocks suffer only a small weight
> penalty over the average aluminum block of only a few years ago.
>
> So - if you are talking no-holds barred performance engines, and
> maintenance/repair costs (as well as production costs) are a secondary
> consideration - yes, OHC engines have an advantage.
> DOHC has a marge larger advantage over SOHC than SOHC has over OHV
> technology when you get into the higher output higher speed engines
> because variable cam geometry is so much easier on a dual cam setup.
>
> This does NOT make a pushrod engine necessarily a lesser engine for
> some 90+% of owners and drivers.

I agree. But I think we also both agree that for high performance
applications OHC engine have inherent advantages that OHV engines can't
match. Remember the 427 SOHC engine Ford had in the 1960s? The OHC
design made it one of the best engines of that era. It was the only
engine that NASCAR banned because it was eating the Hemis alive. The
OHC design made it too durable to run with push rod motors. This also
reminds me of the only turbine car to run in the Indy 500. It bitched
slapped the entire field of cars that year until its gearbox failed with
two laps remaining. I wonder what we would have in today's cars if they
hadn't banned the turbine and SOHC engines? At a minimum I think we
would have seen OHC engines in production cars much sooner.

On Wed, 03 Oct 2007 02:24:40 GMT, "My Name Is Nobody" >
wrote:

Was the 1967 Lincoln 462 the same engine as the 460?
The 460 stroke was shorter and the bore was larger (marginally)
Was the 462 a bored and stroked 430?
>
>Fords 460 was a Lincoln car engine long before it was a truck engine...
>
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