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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

GT40p Heads on a stock 66 289

  • Thread starter Thread starter DJCarbine
  • Start date Start date Feb 2, 2007
D

DJCarbine

New Member
May 4, 2005
392
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0
Feb 2, 2007
#1
  • Feb 2, 2007
  • #1
I got basically everything I need except for the pushrods. Do I need stock length 289 pushrods, or something else. I did a search and couldn't find anything on the subject.


Also, will the stock manifolds bolt up to the heads? Headers will come later, but I want to get the cam broken in without waking up my whole neighborhood
 

Shakin66

Founding Member
Jan 19, 2001
628
1
19
Waycross, Ga / Lake James, NC
Feb 2, 2007
#2
  • Feb 2, 2007
  • #2
I cant help you on the pushrods or the header spacing but is there clearance for the "straight in" plugs? If you want some really good tech help call Ford racing's tech line. They have been a really big help to me building this stroker combo.
 

Z06killinSBF

Member
Apr 25, 2005
457
1
19
McKinney, TX
Feb 2, 2007
#3
  • Feb 2, 2007
  • #3
When I put E7's on my 289, I used the stock length 289 pushrods. As far as the manifolds, I dont know. I do know you pretty much have to run the specific headers or you can get by with using MACs.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Feb 2, 2007
#4
  • Feb 2, 2007
  • #4
I doubt the iron manifolds will clear the "P" head spark plugs. They will bolt up otherwise.
 
6

6cougar8

Founding Member
May 15, 2002
246
0
0
Feb 3, 2007
#5
  • Feb 3, 2007
  • #5
I don't think you will be able to use the stock manifolds. You can use the Tri-Y headers for the P heads or you might be able to use the stock manifolds from an explorer that had the P heads, but I don't know what the flange that connects to the exhaust pipe is like. You might have to modify your exhaust pipes to get it to work.

When I swapped those heads onto my 302 I had to switch to a 5.0 push rod. The rods I had were to short for the bolt down pedestal rockers.
 
D

DJCarbine

New Member
May 4, 2005
392
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0
Feb 3, 2007
#6
  • Feb 3, 2007
  • #6
Do you know the length of the pushrods you had to use? Checking a few sites the stock 289 pushrod is 6.804-6.886 inches long, and the 5.0L (85-96) is 6.272.

A bit confusing to say the least
 

Z06killinSBF

Member
Apr 25, 2005
457
1
19
McKinney, TX
Feb 3, 2007
#7
  • Feb 3, 2007
  • #7
How can the 5.0 pushrods work on a flat tappet cam? The lifters are WAY shorter. That is part of the reason you cant run a converntional roller cam in a 289 with regular roller lifters. Like I said, I used Comp hardened stock 289 length pushrods with adjustable rockers and it works great.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Feb 3, 2007
#8
  • Feb 3, 2007
  • #8
The 79-84 5.0 pushrods are the same length as late 289 rods.
 
D

DJCarbine

New Member
May 4, 2005
392
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Feb 3, 2007
#9
  • Feb 3, 2007
  • #9
So.... stock sized 289 pushrods it is?
 
6

65fast

Member
May 16, 2004
38
0
6
Mt. Airy
Feb 3, 2007
#10
  • Feb 3, 2007
  • #10
Get a length checker and check to be sure. Pushrod length is NOT something to guess
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Feb 4, 2007
#11
  • Feb 4, 2007
  • #11
p heads

This is where I got my headers for the P heads

http://www.fordpowertrain.com/FPAindex/headers1.htm

quite expensive and they do not work with a clutch cable conversion
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Feb 5, 2007
#12
  • Feb 5, 2007
  • #12
DJCarbine said:
So.... stock sized 289 pushrods it is?
Click to expand...

You'd want late 66 to 68 289 pushrods for this. Same valve stem length as the 5.0 heads. And although you should check the geometry, these will be close if not dead on.
 
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