So to start I know this is probably the wrong section to post this in. But it is a bullnose. 1982.

I have a 351w that was rebuilt and bored .030 over, about 25,000 miles and 30 years ago. When the truck was rebuilt it was a totally stock rebuild. It runs great. It only has a two barrel carburetor on it.

So so a few weeks ago I bought some gt40p heads from a junkyard.

My question is does anyone have a full write up on what headers and plug wires I should use? I've seen several different posts on mustang forums but not as much truck stuff.

The truck is 4wd also. I would like mid length headers at least.

Trying to start slowly buying all the parts I'd need here pretty soon.

 

First we will need to know how you plan to use the truck.
If you are going to use back n forth to work on paved roads you would build it one way.
If running on the street pulling heavy loads it would be built another way.
Running off road low range lowish RPM a 3rd way.
Full race mud truck a 4th way.
Right now we don't know how to guide you.
Dave ----

 

Mostly it's going to be used on the street on the weekends. I would like to get close to 300 hp at the crank. So a small cam is what I'm going for, around 260 degrees of duration with .475 of lift.

 

I would run shorty headers and the stock plug wires.

 

Ive read that stock plug wires don't work on gt40p heads. Why not long tubes?

 

I cant say on the wires as I am not into the v8 stuff enough to know/learn at this time.


Long tube headers hang low and get smashed/crushed. I think you have more issues with them sealing to the heads than short tube headers.
I would also say the long tube work better on the upper RPM band to pull gasses out than what you do on a street motor.
Yes you could go smaller tubes to have them work better in the lower RPM range but then suffer in the upper RPM if you need to run there for a little bit.


Just my .02 and I have a set of shorty headers to replace long tube on a classic car I am working on because of the above other than maybe RPM.
Dave ----

 

After researching I found that long tubes for Gt40p heads are impossible to find. So shorties it is. They have weird plug interference with headers also.

 

Are the GT40 heads used on Mustangs only?
If so then that might be why it is hard to find anything to fit other than that and just make do to fit something else.
How you going to hook pipes up to them? Will the car Y pipe fit or just going to make pipes to fit them?


I have to do that on my shorty headers as they are for a Jeep and I am using them in a car replacing long tube headers. For the close out price of half what they normally went for I could not let them go. Even if they don't work I can still sell them for what I got them for.


Sometimes you got to do what you got to do!
Dave ----

 

They generally came on the Mustang Cobras, Explorers/mountaineer, and F150 lightnings.

In my experience BBK headers fit these heads well, but I've only worked with them on Mustangs. I only had a fitment issue once with some unmarked shorty headers, and I swapped them for BBKs and it fit fine.

 

Going out on a limb it sounds like if you went with parts for Explorers/mountaineer, and F150 lightnings they may work for our year truck...word is MAY!
Thanks
Dave ----