Exhaust Factory Exhaust Manifolds

jdemolet

Member
Sep 1, 2013
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Im picking up a set of gt40 or gt40 p heads this weekend at the junkyard. I want to know if the factory 5.0 exhaust manifolds will bolt up to them. I'm not doing headers yet till I go boost then I will go longtubes
 
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Yes, they will bolt up.
But:
You won't be able to remove the spark plugs with the headers in place.
You won't be able to use stock spark plug wires. Even with different wires with angled boots, the spark plug wires probably will not clear the headers.
 
Since I'm on a budget will the stock valve springs work with the stock cam I'm not going to rev past 5200
Do yourself a favor now before you bend or break something and replace the valve springs. If you don't have the money to have the heads taken to a machine shop and have them checked out, the valves ground and springs replaced, you would be better off to wait until you do have the $$ to do it right.

There is always enough money to fix and do it right the second time, but why waste time, $$ and energy by doing it twice? It is for this very reason that there is a Turbo coupe 3:55 disc brake rear axle sitting under my workbench. It needs new clutches in the Trac-lock, new axle bearings and axle seals. Once I have all the parts, I will recruit some help and install the axle. Until then it will sit and wait. I would advise you to follow an experienced example and gather all the parts and machine shop work to do the job first and then do the job Do it right the first time and not have to do it over again.
 
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Heads work in conjunction with other parts. Right now you will be doing a lot of work with little reward.
Will the springs work with the stock cam? Probably, but you are going to make it harder to change them later.

Do the cam, intake, heads and headers at the same time.

I also agree with jricker, have a machine shop valve job and add the springs. Although that is the max I would invest in gt40 irons.

I'd make life easy and just use ford racing shorty p headers.
 
What I meant was I'm budgeting for parts and I wanted to know if the stock springs could handle the lift
No, they cant.

For headers, frpp shorties work perfect, and bbk shorties need 90 degree boots and boot protectors, and will need to come off to change plugs. I believe the bbk lts are the same way as the shorties, and all three of those options should be fairly readily found used.
 
Mac makes garbage that doesn't last and usually has issues lining up.

Just stick with the ford racing p headers, they will go on and off easily.
 
Mac makes garbage that doesn't last and usually has issues lining up.

Just stick with the ford racing p headers, they will go on and off easily.

Thats funny. I live in RI, one of the worst states of the salt belt... Fairly close to the water too. My MAC long tubes were removed and installed MANY times from both my own car, anf the car they came from. They are still in great condition. If I were still using an 8.2" engine, I'd still have them in the car.
 
I've been through two sets of mac headers. First time I was uneducated, second time I was cheap.
Then the 3 in mac catback rotted and fell apart on my explorer.
No more mac lessons for me.
 
If you are using p heads, any header you buy has to be designed to use them. You may find a random set that works, but it will be trial and error.
There isn't that many sets that work. The ford racing ones are the sure bet, that's why I keep mentioning them.
 
You could just look for an early 1996 explorer and see if it has standard GT-40 heads.

Will save you in cost over the P heads as you can use any standard Mustang header.

Still need to upgrade the springs