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302 to 351 (serious, not 5.0 talk style)

  • Thread starter Thread starter fivespeedsteed
  • Start date Start date Dec 16, 2005

fivespeedsteed

20+ Year Stangneter
Oct 17, 2003
748
22
69
Richmond, VA
Dec 16, 2005
#1
  • Dec 16, 2005
  • #1
ok so what is hard about fitting a 351 in a fox. are the mounts different/need to be moved? just the hood fitting issue? is it hard hard to get a 351 in there?
 

carbed87

Member
Jun 5, 2005
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16
Dec 17, 2005
#2
  • Dec 17, 2005
  • #2
no, as far as i know, they're the same damn block casting. so the motors are the exact same size. just the displacement is different.
 

TomCat

New Member
Apr 19, 2005
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Dec 17, 2005
#3
  • Dec 17, 2005
  • #3
http://www.fast351.com/tech/351w.htm

A little info
 
9

9 Deuce GT

Member
Dec 10, 2003
550
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16
Geneva, NY
Dec 17, 2005
#4
  • Dec 17, 2005
  • #4
The blocks aren't quite the same size. They share many characteristics, but the 351W is wider because it is taller. This creates a few issues. The exhaust and intake from a 302 won't fit. Other than that, it is a pretty straight forward swap.

But, to get the big #'s from a 351W, you have got to be able to feed the beast. (fuel, intake)
 

txstang84

15 Year Member
May 21, 2005
1,639
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Tuscola, tx
Dec 17, 2005
#5
  • Dec 17, 2005
  • #5
like duece said, the block is taller and wider; which means that you'll need a new intake, new headers, it also uses a different dizzy-again, increased height. and 351's use a 28 oz flywheel and damper instead of the 5.0's 50 oz...so there's two more parts you need. I've also noticed that some builds require different acc. mounts-not all, but some. things to consider...
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 17, 2005
#6
  • Dec 17, 2005
  • #6
carbed87 - you're misinformed.

The blocks aren't anywhere NEAR the same size - the 302 has an 8.2" deck height; the 351W has a 9.5" deck height; 351C has a 9.2" deck height. The same heads bolt right on the 351W's -- but because the block is bigger, the heads sit both higher and further apart. Consequently, exhaust system changes are required - different headers at least. Hood clearance is usually a problem - although with different mounts or crossmember or really low profile intakes, you can make one fit under the stock hood.

As others have pointed to - 50 oz. balance vs. 28; different lower intake manifold (wider); different distributor (block height); some changes to accessories or at very least a different belt length; don't forget that the engine you'll be bolting in will add a good 75-100 lbs. to the front of the car in similar configuration (both w/alum or cast iron heads)
 

NKau

Founding Member
Dec 15, 2001
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Jefferson, WI
Dec 17, 2005
#7
  • Dec 17, 2005
  • #7
The swap isn't as nearly popular now since it's just as cost effective (or more) to just build a 347 and not have to worry about all of the other issues of swapping in a 351W. The weight savings of the 347 over a 351W is also a nice bonus.
 

Modular2v

Founding Member
Jun 30, 2002
3,222
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99
oklahoma
Dec 17, 2005
#8
  • Dec 17, 2005
  • #8
NKau said:
The swap isn't as nearly popular now since it's just as cost effective (or more) to just build a 347 and not have to worry about all of the other issues of swapping in a 351W. The weight savings of the 347 over a 351W is also a nice bonus.
Click to expand...
very true although with a 351 being in there it has the potential to become a 363/393/408/427 and im sure im missing one
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
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108
Chicagoland
Dec 17, 2005
#9
  • Dec 17, 2005
  • #9
Modular2v said:
very true although with a 351 being in there it has the potential to become a 363/393/408/427 and im sure im missing one
Click to expand...
The one advantage you're probably thinking of is block strength. The 351 can handle a hell of a lot more than the 302 before it breaks.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Dec 17, 2005
#10
  • Dec 17, 2005
  • #10
StangGT1995 said:
The one advantage you're probably thinking of is block strength. The 351 can handle a hell of a lot more than the 302 before it breaks.
Click to expand...


Not really true, the only 351W that are significantly stronger are 69-74, other wise they will break right up the middle like a late model 302 with 600hp or less.
 
B

black92gt

New Member
Aug 7, 2001
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Dec 17, 2005
#11
  • Dec 17, 2005
  • #11
Go 460, and you won't regret it. 460+ ci = Lots of power. Don't be a homo
 
M

macx

New Member
Jul 18, 2004
228
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0
SE Missouri near Cape Girardeau
Dec 17, 2005
#12
  • Dec 17, 2005
  • #12
I went 351 with plans for making it a 393 later.

Here's my experience - every little nut and bolt
that I could think of.

www.lincolnsonline.com/article144.html

If you don't plan to stretch it, I'd definitely
consider a 331 (I'd prefer that cuz of the
somewhat better rod/stroke ratio, rod
angularity and cylinder/piston wear, and
potential for oil burning probs unless you
get something like the Coast HP 347 with
shorter rods to keep the pin out of the oil
rings and offset piston pins to decrease
rod angularity)
 

jrichker

StangNet's favorite TOOL
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Mar 10, 2000
27,512
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Dublin GA
Dec 17, 2005
#13
  • Dec 17, 2005
  • #13
There was a 351 swap sticky posted a few months ago. There was all the part numbers, parts, and recommendations for a 351W engine swap into a 79-93 Mustang. I have it, but it is too big to post. Email me and I will send it to you.
 
M

MatthewP

Founding Member
Dec 7, 2001
355
0
0
Calgary, Alberta
Dec 18, 2005
#14
  • Dec 18, 2005
  • #14
The distributor is not different because of the block height, but because the oil pump driveshaft is a size bigger.

The 351W is a much stronger block than the 302. The hardware is all a size bigger, and the webbing is much more substantial.

-Matthew
 
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