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GT40 P's and egr

  • Thread starter Thread starter jwzg
  • Start date Start date May 2, 2004

jwzg

Member
Apr 6, 2004
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16
Prattville, AL
May 2, 2004
#1
  • May 2, 2004
  • #1
I have a set of GT 40 P heads that I am getting ready to put on a '91 5L.

Questions:

1) Can you run these heads and still have a functioning EGR system?

2) Has anyone here had the Thermactor holes drilled? If so, how much should it cost and does anyone have a picture?

I am NOT going without smog gear as I want this engine to appear VERY stock and I'm pretty green as well .

Thanks!

UPDATE: Question 1 is solved. However, I'm still looking for either some instructions or pictures of what I have to do to get these smog holes drilled.
Any help is appreciated.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
May 2, 2004
#2
  • May 2, 2004
  • #2
If you know you have to/want to run emissions, I think you'd be better off in the long run selling the P's and picking up a set of GT40 irons. There's very little flow difference, and the 40's are already set up just like you need them. And there's a good market for the P's. Anything can be done - but I suspect you'll end up spending more money for not much benefit trying to modify the P's to work. Having said that, I believe the Explorers with the P's had external egr (tube from the header) - perhaps those components are adaptable. Whether or not the non-Explorer ecu can be made to properly actuate an Explorer egr set up -- I have no idea. Another reason to go with GT40's and simply bolt on all your HO stuff.
 

jwzg

Member
Apr 6, 2004
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Prattville, AL
May 2, 2004
#3
  • May 2, 2004
  • #3
Thanks for the input, Michael. However, the heads do have the passages for internal EGR between the #2 and #3 intake ports. It's the late model intake that doesn't have the passages. I guess my question is more related to the holes for the Thermactor system. Does the hole have to be drilled completely through the head or into the rear exhaust port only? That's why I'd like a picture of a head that has had this operation. I just need to know what to show the machine shop. I'm overseas now and ordered the heads online. If home, I'd just look at the stockers and figure it out, but if.... .
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
May 2, 2004
#4
  • May 2, 2004
  • #4
Understand - can't help with the heads that have been drilled for thermactors; as I recall on my GT40 Y303's aluminum heads, that port goes all the way from one end to the other. But I'm operating off of memory - which ain't what it used to be.
 

jwzg

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Prattville, AL
May 2, 2004
#5
  • May 2, 2004
  • #5
Others?? How about a picture?
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
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128
Saint Louis, MO
May 2, 2004
#6
  • May 2, 2004
  • #6
Sorry, no picture but my new GT40P heads were set up with the thermactor holes in them. I have a 97 Explorer intake on them and the stock EGR spacer bored to 65mm. assembles just like the stock intake. I drilled the lower for the EGR coolant return and the ACT sensor. Also converted the Explorer 65mm TB and I'm running the yellow Explorer 19# injectors.
 

jwzg

Member
Apr 6, 2004
237
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Prattville, AL
May 2, 2004
#7
  • May 2, 2004
  • #7
To quote Mel Brooks in Blazing Saddles, "What'll it cost, what'll it cost?!"

Tom, my setup is going to be almost exactly like yours with a Lentech AOD. Do you have any emissions problems? Keep me posted about your times through this thread when you get to the track. BTW why advance the stock cam?
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
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128
Saint Louis, MO
May 2, 2004
#8
  • May 2, 2004
  • #8
I'll have dyno data before track data. No emissions problems yet, but I'
ve only been driving it a week. I have a hesitation just as I advance the throttle on occasion that may be the EGR but I'm waiting to see if it leaves with the EEC relearning things. I advnaced the cam to get the ICL that Buddy Rawls recommended I run the cam at after giving him my valve events.
 

jwzg

Member
Apr 6, 2004
237
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16
Prattville, AL
May 3, 2004
#9
  • May 3, 2004
  • #9
ttt

Any others?
 
M

mackey

Active Member
Jan 25, 2003
1,284
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38
Beverly, Massachusetts
May 3, 2004
#10
  • May 3, 2004
  • #10
I still want to see the answer also. Do the heads have everything needed to work with emissions in my area? Does the EGR still function with these heads? I want to know if they are a straight bolt-on with P headers.
 
M

mackey

Active Member
Jan 25, 2003
1,284
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38
Beverly, Massachusetts
May 3, 2004
#11
  • May 3, 2004
  • #11
http://cgi.ebay.com/ebaymotors/ws/ebayISAPI.dll?ViewItem&item=2476235037

Do those have egr? where is the hole located for it on the heads?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
May 3, 2004
#12
  • May 3, 2004
  • #12
Unfortunately, he hasn't taken his pics in a way to let you see. Email him and tell him you want to see a pic of the intake port side of the head. If equipped, the egr port will be a small hole centered in between the #2 and 3 or #6 and 7 intake ports.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
May 3, 2004
#13
  • May 3, 2004
  • #13
Those heads are not drilled for the Theremactor air system, can't tell about the EGR as Mike said but I doubt seriously they are.
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
May 3, 2004
#14
  • May 3, 2004
  • #14
These are the holes that Mike and Tom are referring to.

This is a pair of GT40 P's

Now about those thermactor holes...

1) cost?

2) how to?
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
May 3, 2004
#15
  • May 3, 2004
  • #15
ttt
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
May 4, 2004
#16
  • May 4, 2004
  • #16
I hate to keep bringing this topic up, but I know that within the vast community that is stangnet, someone has actually had drilled a set of 40Ps for smog. Help please
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
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119
Antelope Valley, SoCal
May 4, 2004
#17
  • May 4, 2004
  • #17
Go to http://www.stangpro.com/, then click on Articles, then the GT-40P article. It has cross-sections of both intake and exhaust ports and apparently alot or all GTPs have thermactor bosses, but not all are drilled(or something like that). The pictures lead me to believe it can be done and Ford actually provided for the possbility. I have no idea what it would cost as it would vary from shop to shop, but would guess anywhere from $100-250.
 
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