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  • SN95 4.6L Mustang Tech

Are the 4.6's and 5.4's big blocks or small blocks?

  • Thread starter Thread starter 1badII
  • Start date Start date Dec 8, 2003
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Slithering_Joe

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Feb 15, 2002
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North Jersey SouthEast PA, USA
Dec 9, 2003
#21
  • Dec 9, 2003
  • #21
GTGunner said:
Modular motors are physically 'wider' due to the 90 degree angle formed by the right and left sides of the block in relation to the crankshaft. In other words, the 'V' of the V8 on a modular motor is a 90 degree angle, whereas the angle of the 'V' on the older Ford small blocks (260, 289, 302 and 351W) is more along the lines of a 60-70 degree angle. Therefore, even though the displacement on the 4.6 is smaller, the 90 degree angle makes it wider than the older Ford small blocks that sported larger displacements. Also, stock DOHC and SOHC heads are wider than the stock heads that came on old Ford small blocks.
Regards,
GTGunner
Click to expand...

The mod motors are wide because the height of the heads are huge since the cams sit on top.

The V8's you speak of above from Ford are ALL 90 degrees. In fact, I can't think of any V8 (Ford, GM, Chrysler...) that isn't 90 deg. Not sure about the small V8s like the SHO and the LS for example.

The term "big block" and "smal block" are old school terms and really don't apply to the modular motors.
 

demonspeed

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Jul 14, 2001
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Dec 9, 2003
#22
  • Dec 9, 2003
  • #22
lwkauble said:
Actually, it goes like this:

Small block Fords are:

221 CI, 260 CI, 289 CI (Reg and high po w/mechanical lifters), 302 (5.0L), Boss 302, 351W (5.8L), Ford Classifiies the 351C as a small block with big block attitude is the first of the 335 series family (same heads as boss 302), 351M and 400M (a modified cleveland block with a taller deck height .500), the gas efficient (yeah right) 255CI introduced in 78-79.
Click to expand...

So what do they call the 351M?
 

SilverSteed

Member
Dec 31, 2002
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Dec 9, 2003
#23
  • Dec 9, 2003
  • #23
1badII said:
How come the 427 Cammer isn't considered a mod motor?
Click to expand...
Its not a mod motor, because mod motor is the name ford gave to the newer ones because alot of the parts are interchangeable/or not much different so they can use some of the same dies and such during production to save money.

Andy
 

351CJ

New Member
Dec 11, 2002
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Dec 9, 2003
#24
  • Dec 9, 2003
  • #24
GTGunner said:
Modular motors are physically 'wider' due to the 90 degree angle formed by the right and left sides of the block in relation to the crankshaft. In other words, the 'V' of the V8 on a modular motor is a 90 degree angle, whereas the angle of the 'V' on the older Ford small blocks (260, 289, 302 and 351W) is more along the lines of a 60-70 degree angle. Therefore, even though the displacement on the 4.6 is smaller, the 90 degree angle makes it wider than the older Ford small blocks that sported larger displacements. Also, stock DOHC and SOHC heads are wider than the stock heads that came on old Ford small blocks.
Regards,
GTGunner
Click to expand...

This is not correct

All Ford V8's, are 90 degree V engines.

8 cyl engines have to be 90 or 180 degrees in order to get an even firing order without resorting to split rod journals on the crankshaft.

6 cyl V engines such as the Duratec 2.5 & 3.0 and the Vulcan 3.0 are 60 degree engines.
 

351CJ

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Dec 11, 2002
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#25
  • Dec 9, 2003
  • #25
demonspeed said:
So what do they call the 351M?
Click to expand...

The 351M is bastard engine.

At the end of 1974 Ford shut down production of the 351C engine and shipped the tooling to Australia (Those lucky SOB's).

In a year Ford found it couldn't keep up with demand for 351W engines so it took the 400 block and put in a new crank and rods to shorten the stroke and reduce the displacement back down to 351 CID. They called this abomination the 351M.

Stupidest thing Ford ever did was to discontinue the 351 Cleveland.
 

351CJ

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Dec 11, 2002
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#26
  • Dec 9, 2003
  • #26
forpit2000gt said:
Thanks for the info, I believe I was told this years ago. 289 and 302 block same, different stroke.?? same with 429 and 460, same block , you get the addition displacement from bore and stroke. I never thought about the mod motor, I thought it was all by itself, a mod motor. Technically, it may be the end results of Mazda being involved with Ford, or at least someone has paid attention to the imports at some time or another..( is that blasphemy???)
Click to expand...

The 289 & 302 have very similar blocks both with a 4.00" bore. The difference in displacement is due to the stroke.

Same with the 429 / 460, they have the same block and same bore, just a different stroke.

The Modular V8 Family has nothing to do with Mazda. The idea of the Modular family was that the same basic engine configuration could be made as a V6, V8, V8, or V12 using the same bore spacing and basic engine geometry. In addition different heads, SOHC, DOHC could be bolted onto the same blocks. Much of the same production tooling could be used on different engine models.

The V6 version of the Mod motor never saw the light of day as 90 degree V's do not make for good V6 engines, too big, too heavy and requries split rod journals to get an even firing order.

As you guys are aware, the V8 and V10 mod motors are the only ones that made it into production.
 

351CJ

New Member
Dec 11, 2002
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#27
  • Dec 9, 2003
  • #27
lwkauble said:
Actually, it goes like this:


in 1962 came the 406/427 Single cam motors. The significantly different cammer 427 SOHC was banned from NASCAR because of unfair advantages.

1966 uhsered in the 428 a low reving high torque motor originally designed for station wagon and family car use such as galaxie.
Click to expand...

Actually that is not quite corrcect.

In 1962 the 406 was introduced. It is a pushrod engine. 4.13 bore x 3.78 stroke.

In 1963 the bore was increased to 4.23" making it 425 CID, but Ford called it a 427.

The 406 and 427 were intended as race car engines. They had solid lifters and used the famous side oiler block.

In 1965 the 427 SOHC Cammer came out. It was never sold in a production car and is was never raced in NASCAR. NASCAR made a decision in 1965 to NEVER allow OHC engines. A decision is still sticks with today. You could buy a 427 Cammer as a crate engine at your local Ford dealer.

The 428 was introduced in 1966. Since it's bore is bigger than its stroke, 4.13 x 3.98, you can't exactly call it a long stroke station wagon engine. In fact most of the famed 427 Shelby Cobras had 428 engines. You only got the 427 side oiler if you bought the race model of the Cobra. The street 427 Cobras came with 428 engines.

A somewhat popular mod. for 427 engines is to put the 428 crank in it which gives you 447 CID and a lot more low end torque.
 

Slithering_Joe

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Feb 15, 2002
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North Jersey SouthEast PA, USA
Dec 9, 2003
#28
  • Dec 9, 2003
  • #28
351CJ said:
90 degree V's do not make for good V6 engines
Click to expand...
What about GM's 4.3L V6?
 

forpit2000gt

Founding Member
Jun 30, 2002
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Columbia, SC
Dec 9, 2003
#29
  • Dec 9, 2003
  • #29
Slithering_Joe said:
The mod motors are wide because the height of the heads are huge since the cams sit on top.

The V8's you speak of above from Ford are ALL 90 degrees. In fact, I can't think of any V8 (Ford, GM, Chrysler...) that isn't 90 deg. Not sure about the small V8s like the SHO and the LS for example.

The term "big block" and "smal block" are old school terms and really don't apply to the modular motors.
Click to expand...
SHO engine is a Yamaha
 

Slithering_Joe

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Feb 15, 2002
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North Jersey SouthEast PA, USA
Dec 9, 2003
#30
  • Dec 9, 2003
  • #30
forpit2000gt said:
SHO engine is a Yamaha
Click to expand...
And your point is?
 

forpit2000gt

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Jun 30, 2002
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Dec 9, 2003
#31
  • Dec 9, 2003
  • #31
that it is not a Ford Engine, also I will check to be sure but I don't believe all the engines are 90 deg v. Where do you get your info... now I am wondering If I am correct. I have not built many engines, but I have torn a lot down for others. I seems that most were about 60 deg v.
 

demonspeed

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Jul 14, 2001
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Evans City, PA
Dec 10, 2003
#32
  • Dec 10, 2003
  • #32
351CJ said:
The 351M is bastard engine.
Click to expand...

Interesting... My buddy has one in his 79 Broncho.
 

Slithering_Joe

Founding Member
Feb 15, 2002
242
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North Jersey SouthEast PA, USA
Dec 10, 2003
#33
  • Dec 10, 2003
  • #33
forpit2000gt said:
that it is not a Ford Engine, also I will check to be sure but I don't believe all the engines are 90 deg v. Where do you get your info... now I am wondering If I am correct. I have not built many engines, but I have torn a lot down for others. I seems that most were about 60 deg v.
Click to expand...

It may be built by Yamaha but there are quite a bit Fords with them in it. You must be tearing down a lot V6's then.
 

Roger Ramjet

New Member
Oct 31, 2003
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Southern Maryland
Dec 10, 2003
#34
  • Dec 10, 2003
  • #34
Monkie said:
I still think its dumb as hell that Ford has a 4.6L V8. It should ATLEAST be a 5.4L V8 since it has OHCs.
Click to expand...

I'm with you!

I keep asking why Ford would want 2 different deck height blocks. Seems dumb to me! Different bores or strokes on the same block makes more sense.
 
1

1badII

Member
Aug 5, 2003
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Durham, North Cacalaky
Dec 10, 2003
#35
  • Dec 10, 2003
  • #35
demonspeed said:
Interesting... My buddy has one in his 79 Broncho.
Click to expand...
They're good truck engines. They make good low end torque.
 
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