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Ive got a 1967 fairlane 390gta ive got hooker super comps headers for it but havnt installed them yet. the engine was re-built about 5 years ago and the mechanic at that time told me that these stock headers for this 390 breathe good, so i didnt install them at that time. just did the exhaust stright back to 3 chamber flowmasters. the bottom line is i bought the headers for them back then still have them, wanna install them but i heard they r a pain to install? if anyone has installed headers on a 390 gta ford fairlane and can help it would be greatly apprecaited.
 

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Ive got a 1967 fairlane 390gta ive got hooker super comps headers for it but havnt installed them yet. the engine was re-built about 5 years ago and the mechanic at that time told me that these stock headers for this 390 breathe good, so i didnt install them at that time. just did the exhaust stright back to 3 chamber flowmasters. the bottom line is i bought the headers for them back then still have them, wanna install them but i heard they r a pain to install? if anyone has installed headers on a 390 gta ford fairlane and can help it would be greatly apprecaited.
If they are super comp then they are not stock, they are 3 inch unless you have the street hookers. Both sets , the left side comes apart for a easy fit . I stated in your other post how to put them on.
 

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As well after you have them on you will see the header is touching the oil filter or so close you have a consern. You can have a bracket made to allow the oil filter to go over to one side fauther if you donot like it touching. They all are too close for my liking.
 

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Ive got a 1967 fairlane 390gta ive got hooker super comps headers for it but havnt installed them yet. the engine was re-built about 5 years ago and the mechanic at that time told me that these stock headers for this 390 breathe good, so i didnt install them at that time. just did the exhaust stright back to 3 chamber flowmasters. the bottom line is i bought the headers for them back then still have them, wanna install them but i heard they r a pain to install? if anyone has installed headers on a 390 gta ford fairlane and can help it would be greatly apprecaited.
The stock cast iron "headers" on the 390GT engines do not flow very well. A set of aftermarket tubular headers are going to be a considerable upgrade, but as stated, will likely be a considerable amount of additional work.

How much benefit you would get out of making the swap will depend a good deal on how much the motor was modified. The more greater the build, the greater the benefit.

Best of luck!
Paul

1969 R-Code, 4-Speed, Drag-Pack Cobra Fastback Project
1967 Mercury Commuter Wagon w/mild 429

My Car Restoration Projects
 

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What is the casting number on your head and the part number for the headers? Odds are those Supercomp headers are for a Cobrajet not for a 390GT.

They are not the same, there is a minor problem of bolt pattern, but a second problem that a 390GT head has a lower exhaust port in relation to the bolts.

To get the gasket to seal, you need to slot all the bolt holes and lower the headers on the heads by up to .250, but you can often get by with a little less

As far as whether its worth it...the two most beneficial things for any FE are headers and a distributor recurve. Its absolutely worth it, and your mechanic was mistaken, 390GT manifolds are miserable
 

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I'm not familiar with the Hooker headers, but before you seriously dive into it. Check the bolt pattern of the headers. The GT heads you have should be 14 bolt flanges. 14 bolt heads have the top end bolts dropped down about 1/4". Depending on the headers, they made be flanged for the 16 bolt heads. Another thing to think about, is your car auto or manual, if manual readup to see if you will have problems with the z-bar.

As for the stock manifolds, the breathability of the drivers side isn't nearly as bad as the passengers side. When you look at the exhaust port orientations, you can see that the back 2 ports are angled towards the front 2 ports and vice-versa, which inhibit the scavenging ability of the exhaust, i.e., the exhaust in-a-sense fights each other. This is why I stated the drivers side isn't nearly as bad as the passengers side because the exhaust exits between the 2nd and 3rd cylinder on that side, however for the passengers side, the exhaust exits behind the rear cylinder thus the exhaust flow has to bouce back off another exhaust ports pulse or the front of the manifold. This effects the scavenging of the exhaust fumes out of the cylinder.

As far as installing them, I wont lie, its rather a pain. It can be done in a weekend. It just takes a few hours, some skint knuckles and a few choice words thrown in along the way. I cheated on mine as I was building the engine and waited to put the heads on till after the engine block and headers were sitting in the car.
 
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