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351W Foxbody?

  • Thread starter Thread starter xxtavixx
  • Start date Start date Jun 18, 2004
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xxtavixx

New Member
Sep 6, 2003
59
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0
Jacksonville, Fl
Jun 18, 2004
#1
  • Jun 18, 2004
  • #1
What exactly is needed to this, go from either a LX or a GT (I'm not sure if going from a 4 cyl would be worth it, but there are a lot more of them) to a 351. Of course I would need the block, the headers and exhaust back. I know a lot of the heads can be used, but what about Intake Manifold? I plan on eventually running boost, so of course I'm going to probably want to run forged internals. So here are some questions....

Tolerance wise, how good are the rods and crank? Pistons are getting replaced with either 8.5 or 8.0

I know there are some difference in years for the 351, and from what I understand 69-73 are the years to go with because they're stronger (Why? Is it a 4 main bolt?)

Any help in this would be greatly appreciated. Thankyou

-Andrew
 

Venom4.6

Founding Member
Jun 30, 2002
1,356
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Saint Louis, MO
Jun 18, 2004
#2
  • Jun 18, 2004
  • #2
Here's a decent write up of a 351 swap. Also do a search on the topic here. Plenty of info.
http://www.fast351.com/index.htm
 

ironmedic

New Member
Mar 18, 2003
1,361
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Puyallup, WA
Jun 18, 2004
#3
  • Jun 18, 2004
  • #3
you need a different lower intake cuz its slightly wider than a 302. if i understand right, the upper intake will still fit.
 

squall9393

New Member
Feb 7, 2004
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Oceanside, CA
Jun 18, 2004
#4
  • Jun 18, 2004
  • #4
Here are the differences in years:

Casting Numbers, Ford Part Numbers, Bore, and Deck Heights

351W 1969-70: Casting: C9OE-B D1AZ-E, P/N: C9OZ-B, 4.00", 9.480"

351W 1971-74: Casting: D2AE-BA D1AZ-E, P/N: C9OZ-B, 4.00", 9.480" (9.503" In 1974)

351W 1971-74: Casting: D4AE-AA D1AZ-E, P/N: C9OZ-B, 4.00", 9.480" (9.503" In 1974)

351W 1975-78: Casting: D4AE-DA D1AZ-E, P/N: C9OZ-B, 4.00", 9.503"

As far as swapping a 5.0 for a 351W your gonna need a different oil pan and pick-up tube, yes a new lower intake for the wider lifer valley, a 1/2" spacer for the crank pulley, obviously a 5.8L distributor, lets' see- yeah definitely new headers because the old ones won't reach the stock H-Pipe, a new harmonic balencer and flywheel balenced to 28oz. because the 302s were balenced to 50oz., possibly new motor mounts if your old ones are worn when you pull the old motor out, new assessory bracket if your keeping A/C and power steering, and most likely you'll need a cowl hood because of the increased deck height of the motor won't fit under the stock hood. Hope any of this helped.
 
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xxtavixx

New Member
Sep 6, 2003
59
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Jacksonville, Fl
Jun 18, 2004
#5
  • Jun 18, 2004
  • #5
I've been searching and still can't find out the power tolerances for the block, crank, rods or pistons. I've got a guy selling a block with TRW forged dished pistons (Dont know the CR). From everything I've read the stock setup is good for 600whp, at that point something inside the block gives up. I'm hoping the block is good for at least 900hp. But what of the rods, crank and pistons?
 

hllon4whls

BANNED
Founding Member
Jan 17, 2002
2,567
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46
Covington
Jun 18, 2004
#6
  • Jun 18, 2004
  • #6
900 hp is going to be pushing it for a stock block. It all depends on how you spin it. If your goal is 900, you need a forged crank anyway, so dont even worry about the stocker. You are going to need a good crank and rods and pistons. Might as well do a stroker. If you keep it under 6200 or so, it might live for a while in a stock block.

Sounds like what you want is a dart block.
 
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xxtavixx

New Member
Sep 6, 2003
59
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0
Jacksonville, Fl
Jun 18, 2004
#7
  • Jun 18, 2004
  • #7
Problem is I dont exactly want to pay 2000 shipped for a block, and then machine it (Another $1000) and then put forger internals in there. That's probably going to rack up a nice 5000 bill. I'm not entirely sure what needs to be machined, is it just the pistons routes? So really what it comes down to is one simple question, will the block physically hold that much power? If it can hold it, I'd be cool with that. I'm not looking to make insane power, just want some room for safety. I'd probably be completely happy with 6-700, but a stock 302 can't take that either. And maybe turn the boost up every once and a while


EDIT-In terms of the lower intake manifold, I guess that means the 5.0 aftermarket manifolds will not bolt up will they? I'll have to look around to see if any aftermarket lowers are made, but I supposed I could use the GT40 IM off of a 351W and a better flowing upper that's port matched. That is unless the 5.0 aftermarket lowers fit
 

hllon4whls

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Founding Member
Jan 17, 2002
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Covington
Jun 18, 2004
#8
  • Jun 18, 2004
  • #8
The 302 manifolds will not bolt up to the 351. It is too wide.

600-700hp in a 351 is fine. There are some good fulie manifolds for the 351.
 
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xxtavixx

New Member
Sep 6, 2003
59
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0
Jacksonville, Fl
Jun 19, 2004
#9
  • Jun 19, 2004
  • #9
Thankyou
 

OonDeanisS

Founding Member
Jun 16, 2002
902
1
19
Danbury, CT
Jun 19, 2004
#10
  • Jun 19, 2004
  • #10
im selling my car if you want a head start on the project -see sig
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
1
0
St.Petersburg,FL
Jun 19, 2004
#11
  • Jun 19, 2004
  • #11
A stock 351W block from 69-74 will hold 700hp and 7000rpm (-50hp and -200rpm for later blocks)with threaded block plugs,main studs,and no more than a .30 over bore.You could fill the water jackets with block filler to make it stronger and bore it larger.What I would look for a 74 block because the deck hieght is 9.5 and most 351W strocker kit are for this deck hieght.I would put the Milodon main caps on with a main griddle and windage tray and use ARP 220,000psi main studs.Ford sells the threaded block plug kit which will strenghtin the side wall.Add some block filler and it's good for 850hp and 7500rpm.
 
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