This is topic Are GT40Ps smog legal? in forum Tech Talk at Northern California Ford Owners  .


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Posted by Fox89GT (Member # 1539) on :
 
Just curious... If I install a set of these, Cobra intake and still keep the stock cam will I pass smog? I'm assuming that since these heads were on the SUVs to begin with that they would be okay. What about the Ford Racing version? Are they the same head? Anyone running these heads passed CA smog testing?
 
Posted by 99gt-UJSTLST (Member # 584) on :
 
the should pass smog with no problems
 
Posted by cobraman_1994 (Member # 467) on :
 
i sure hope so or me and all the other 93-95 cobra owners are going to have "issues"
lol
 
Posted by Fox89GT (Member # 1539) on :
 
Looking through the Summit mag, they sell the Ford Racing GT40P head and usually they mention if its 50 state smog legal or not but this ad did not say anything about it so thats my question.
 
Posted by FasterDamnit (Member # 442) on :
 
The smog injection ports are not open on those heads. Technically not smog legal unless the heads are drilled out. Once on the car I doubt anyone would know the difference.
 
Posted by st5150 (Member # 51) on :
 
quote:
Originally posted by cobraman_1994:
i sure hope so or me and all the other 93-95 cobra owners are going to have "issues"
lol
Actually the cobras and lightnings came with regular GT40's, not the GT40-P's. Do a search for "GT40-P TECH PAGE" for info on the differences.
 
Posted by Glenn (Member # 520) on :
 
quote:
Originally posted by st5150:
quote:
Originally posted by cobraman_1994:
i sure hope so or me and all the other 93-95 cobra owners are going to have "issues"
lol
Actually the cobras and lightnings came with regular GT40's, not the GT40-P's. Do a search for "GT40-P TECH PAGE" for info on the differences.
GT40-P's are from the explorer's I believe.

[ September 06, 2002, 05:39 PM: Message edited by: Glenn ]
 
Posted by street_illegal_stang (Member # 1554) on :
 
yes,explorers carried gt40p cast heads..
you might be able to find the smog rating
on the explorer then compare it to your stang.
how much did you gain over stock heads?
did you have to use the gt40p headers to?
 
Posted by Glenn (Member # 520) on :
 
quote:
Originally posted by street_illegal_stang:
yes,explorers carried gt40p cast heads..
you might be able to find the smog rating
on the explorer then compare it to your stang.
how much did you gain over stock heads?
did you have to use the gt40p headers to?
Any time you use the GT-40P heads you need to get different headers. The Spark Plugs are place differently, you can see about 30-40 HP gains with these heads, and a cobra intake. I actually have that combo being sent to me, it is used, GT-40P Heads, headers, and a cobra Intake, all for the fox bodies. the heads have 1.6 r/r as well. I might sell the whole thing, because I can't use the headers, and intake, so might as well sell it together. Let me know if you are intersted... Anyone.

[ September 06, 2002, 07:55 PM: Message edited by: Glenn ]
 
Posted by Fox89GT (Member # 1539) on :
 
Glenn, got any more info one the set you have coming? Have the heads and/or intake been touched? Why did the original owner sell them? Why are you thinking of selling them? How much are you thinking of asking?
 
Posted by sic91sleeper (Member # 779) on :
 
So if you got gt 40 p heads on a 87-93 stang what kind of headers would you need, what brand, and how much do the headers cost?

I was just looking into these heads not too long ago and maybe get some port work done on them.
 
Posted by PunkINa5.SLOW (Member # 10) on :
 
just put some afr 165s on the car and leave the GT40ps for the other guys.
 
Posted by phildog (Member # 1214) on :
 
The GT-40p's require different headers( MAC and Ford Racing being the only vendors) and they are quite fun(not) to change plugs with the straight plugs. If you're gonna go to all the trouble to change heads, save up some more dough and get some real heads like AFR's, Brodix, etc. The GT-40p's are better than stock, yet I don't think the hassle of switching heads is worth putting on a small head like a GT-40p. By the way, my car had GT-40p heads and passed smog like a champ.
 
Posted by st5150 (Member # 51) on :
 
phildog- what cam and intake did you run with your P heads? Any track times or dyno numbers?
 
Posted by st5150 (Member # 51) on :
 
I forgot to add that many long tube headers like BBK's, Bassani, ect also work with P heads.

Here is all the GT40P tech info you'll ever need:

http://www.jason.fletcher.net/tech/offsite/gt40p.htm
 
Posted by sic91sleeper (Member # 779) on :
 
quote:
Originally posted by PunkINa5.SLOW:
just put some afr 165s on the car and leave the GT40ps for the other guys.
Will do Dan
 
Posted by Glenn (Member # 520) on :
 
quote:
Originally posted by Fox89GT:
Glenn, got any more info one the set you have coming? Have the heads and/or intake been touched? Why did the original owner sell them? Why are you thinking of selling them? How much are you thinking of asking?
It was on my bro's car, he is going bigger and better, I too want to go bigger and better, he is supposed to be bringing out the combo in Oct. I want to get atlast $900 for everything. LEt me know.
 
Posted by JimmysblownFiveO (Member # 1265) on :
 
i have those heads they suck
 
Posted by phildog (Member # 1214) on :
 
I ran a GT-40p headed long block from Cental Coast Mustangs with a Cobra intake, 65mm TB, 24lbers, stock cam with 1.7 Cobra rockers and other assorted goodies and bolt ons. The car ran 13.7 @ 103 with no traction, spinning 1st and 2nd with a 2.0 60 ft on street tires. I yanked that motor for something which will be a bit wilder...
 
Posted by sic91sleeper (Member # 779) on :
 
quote:
Originally posted by phildog:
I ran a GT-40p headed long block from Cental Coast Mustangs with a Cobra intake, 65mm TB, 24lbers, stock cam with 1.7 Cobra rockers and other assorted goodies and bolt ons. The car ran 13.7 @ 103 with no traction, spinning 1st and 2nd with a 2.0 60 ft on street tires. I yanked that motor for something which will be a bit wilder...
Doesnt sound like you were spinning them too much with a 2.0 60ft.
 
Posted by phildog (Member # 1214) on :
 
I wasn't spinning out of the hole because I was lauching at idle and babying the throttle, doesn't matter anymore, the most of the old suspension, the rearend and the motor are now out of the car, replaced with better equipment, so we'll never know what might have been...but I wouldn't buy those heads again.
 
Posted by 93venom (Member # 778) on :
 
I pretty sure that cast iron gt40p's went on the 93-95 cobras. And regular 5.0 headers (frombbk,mac,fms whoever) should bolt up but the spark plugs are bitch because of the wierd angle on the gt40ps. I had to buy special plugs from ford for these heads, but yes, ford sells the correct headers for these heads. just go buy a set of aluminum 50 state heads,
 
Posted by MustangSS (Member # 1689) on :
 
I was just down at the parts store the other day at Serramonte Ford and the tech guy down there told me if I want to be smog legal to go all GT-40 because they are street legal. I asked him about the P's and he told me anything with the GT40 name on it is street legal. That's supposedly the whole point of the GT40 product line.
 
Posted by FasterDamnit (Member # 442) on :
 
WRONG!
The GT40P's are not smog legal for 5.0 Mustangs because they do not have the air injection ports that are needed for the smog pump system. Doesn't mean you can't bolt a set on and get away with it. There are smog legal ones available that have been modified. Central Coast Mustang, I think...

GT40X and Y heads are smog legal from FRPP.
JL
 
Posted by 93venom (Member # 778) on :
 
according to the latest frpp catalogue, gt40ps are smog legal, and gt40x and y heads are not, just thought you guys would like to know that, straight outta the cataloge
 
Posted by O.G. Cobra (Member # 747) on :
 
quote:
Originally posted by 93venom:
I pretty sure that cast iron gt40p's went on the 93-95 cobras. And regular 5.0 headers (frombbk,mac,fms whoever) should bolt up but the spark plugs are bitch because of the wierd angle on the gt40ps. I had to buy special plugs from ford for these heads, but yes, ford sells the correct headers for these heads. just go buy a set of aluminum 50 state heads,
the cobra's had regular gt-40 heads. gt-40p's were on the 5.0 explorers...
 
Posted by shade-tree (Member # 298) on :
 
fasterdamnit is right, they are not smog legal for stangs "out of the box" as in from an explorer. On the explorer they are smog legal because the EGR setup is similar to SN-95 stangs.

Either you drill the back of the heads to get to the exhaust port so that you can plumb that in to your EGR system or you cross your fingers and *hope* to pass smog. Your computer will throw the (EGR does not switch) code when you are bypassing this.

How do I know this? I ran a set of GT-40P heads on my mustang last year, and this year I am running an SN-95 longblock ('94 cobra) motor in my car.

For what it's worth, my old-school MAC 1 5/8" longtubes fit GT-40, GT-40P, E7TE, and Trickflow TW heads perfectly. Tonight I will find out if they clear a McCleod steel bellhousing. If they do, I nominate these headers for the "best header ever" award. [worship]
 
Posted by Fox89GT (Member # 1539) on :
 
Lets take this one step forward. What are the differences between the Explorer and SN-95 EGR setup? I know the intakes are different but what about the heads? By the way where is all this EGR stuff located? I was trying to figure all this stuff out but never did. But then again I did not know what I was looking for????
 




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