GT40P Bronco Hut Headers

[pennyduke]

Just thought I would share how well the Bronco Hut GT40p Shorty Headers fit my 1972 302. They installed in 20 minutes and I have plenty of spark plug clearance. Nice job Bronco Hut. Very happy customer...

 

[Broncos n' VWs]

Those look great! I'll have to consider these when I cross the "motorswap" bridge.

 

[pennyduke]

They are well worth the money. Also in picture #1 you can see the Wild Horses Custom Steering Shaft. Another fine work of art. Thank you Wild Horses. Getting closer to startup...

 

[Wyflyer]

If putting them on late model GT40P heads be sure and ask for the gaskets when you order, they are special small opening gaskets to correct the cylinder to header port mismatch.

 

[76YETI]

Just installed mine too...look and sound great also lowered under hood temp by half!

 

[pennyduke]

Yes, They also sent me the correct gaskets and Bolts.

 

[DirtDonk]

I wonder with all the talk of the exhaust ports being the choke point all these years, why they went and made them even smaller during the last hurrah of the engine?
The P heads are actually supposed to make more power, and certainly burn cleaner (I think the main reason for the changes), but strange that it does so with even smaller exhaust ports!

I wonder if they were trying to get more velocity to compensate for something?
Guessing too that they only cared about lower rpm running in Explorers, as opposed to max breathing.
I've seen flow charts, but will have to look again to see what's up at the higher rpms ranges.
I know mine is wicked responsive from off-idle to 3500 rpm or so, but with the stock cast-iron Explorer manifolds it definitely falls on it's face at higher rpms. I can't wait to try headers someday (without modifying the head at all) to see what kind of a difference I can "feel" from the seat.

Enjoy yours for sure! Let us know how they run. And REV!

Paul

 

[Joe473]

I wonder with all the talk of the exhaust ports being the choke point all these years, why they went and made them even smaller during the last hurrah of the engine?
The P heads are actually supposed to make more power, and certainly burn cleaner (I think the main reason for the changes), but strange that it does so with even smaller exhaust ports!

I wonder if they were trying to get more velocity to compensate for something?
Guessing too that they only cared about lower rpm running in Explorers, as opposed to max breathing.
I've seen flow charts, but will have to look again to see what's up at the higher rpms ranges.
I know mine is wicked responsive from off-idle to 3500 rpm or so, but with the stock cast-iron Explorer manifolds it definitely falls on it's face at higher rpms. I can't wait to try headers someday (without modifying the head at all) to see what kind of a difference I can "feel" from the seat.

Enjoy yours for sure! Let us know how they run. And REV!

Paul

Paul,

I have the non p-heads on the 347 with the BC headers and a not so great flowing 2 into 1 system. It's the 35-349 cam and an autolite 4100. It can climb a grade in 2nd gear at 1000 rpm and it quickly bounces off the Rev limiter set at 6200 if you get into the skinny pedal. I actually think a little less cam would be good for my combo but it's still torquey.

I belive that last version ford was looking for torque and with the small cam and exhaust it did well. If you read up on the mustang sites where the gt 40 heads make real power close to aftermarket heads is with careful exhaust porting.

On the headers the BC wildhorses and Bronco hut headers all have their strong points. I went with the BC in the end to use their head pipes and likes the stock ish style no gasket flange. If going bigger than a 347 that you want to rev I would go with the bigger tube and ceramic shorties for better clearance and temp controls under the hood.

Sent from my SM-G900V using Tapatalk

 

[doghows72]

Gaskets?? I have those headers as well and they are made by Sanderson. They recommend using high temp silicone around each port, let it dry then install. They told me the headers would leak if you use a gasket??
Anyone had any trouble using the gaskets and having leaks? They sure would be a lot easier than that mess I made using the silicone they recommended.
They are very nice though. I also used the WH steering shaft Alison a very nice piece!

 

[pennyduke]

MR. Gasket #5930 is what they sent me. 1.12"x1.48" port 320-351W cid

 

[Jasonj105]

I’m looking at the GT40p Heads. Is there a significant difference when slapping them on a stock 302 short block? I’m reading mixed reviews and looking for more real world experience. Looking at a stock 302, RV cam and the GT40p Heads.

 

[sykanr0ng]

I wonder with all the talk of the exhaust ports being the choke point all these years, why they went and made them even smaller during the last hurrah of the engine?
The P heads are actually supposed to make more power, and certainly burn cleaner (I think the main reason for the changes), but strange that it does so with even smaller exhaust ports!

I wonder if they were trying to get more velocity to compensate for something?
Guessing too that they only cared about lower rpm running in Explorers, as opposed to max breathing.
I've seen flow charts, but will have to look again to see what's up at the higher rpms ranges.
I know mine is wicked responsive from off-idle to 3500 rpm or so, but with the stock cast-iron Explorer manifolds it definitely falls on it's face at higher rpms. I can't wait to try headers someday (without modifying the head at all) to see what kind of a difference I can "feel" from the seat.

Enjoy yours for sure! Let us know how they run. And REV!

Paul

Strangely enough the GT40P head engines have a torque peak 100RPM higher than the non-P head engines.
That is comparing stock Explorers with stock Explorers.

 

[Timmy390]

Gaskets?? I have those headers as well and they are made by Sanderson. They recommend using high temp silicone around each port, let it dry then install. They told me the headers would leak if you use a gasket??
Anyone had any trouble using the gaskets and having leaks? They sure would be a lot easier than that mess I made using the silicone they recommended.
They are very nice though. I also used the WH steering shaft Alison a very nice piece!

I might try the RTV next. I had small leaks with stock gaskets and now I'm using mr gasket dead soft aluminum but still got a few spots leaking. I may retorque them first after I get this dang Samurai out of my shop.

Tim

 

[pennyduke]

I did a lot of searching before I decided to use the GT40p heads. Most threads were from the Mustang forums. Many people are still using them and making tons of torque and HP. Engine builders are saying that improving your heads is the best way to make gains to any motor. Make sure to upgrade the valve springs and get the Bronco Hut Headers.


At this point, I have only completed the break in on my motor, So I can't tell you how it performs. But it sure does sound good with those heads,Thumper Cam, and headers.

 

[Eoth]

Gaskets?? I have those headers as well and they are made by Sanderson. They recommend using high temp silicone around each port, let it dry then install. They told me the headers would leak if you use a gasket??
Anyone had any trouble using the gaskets and having leaks? They sure would be a lot easier than that mess I made using the silicone they recommended.
They are very nice though. I also used the WH steering shaft Alison a very nice piece!

I used gaskets and everything is fine.

 

[DirtDonk]

I’m looking at the GT40p Heads. Is there a significant difference when slapping them on a stock 302 short block?

Difference in what? Overall performance? Fitment of headers?
Assuming you mean performance, but I'm not sure I've ever read here of a member simply bolting a set on without doing all sorts of other things that would have skewed the results completely.
Are you running headers and exhaust now, or is it all stock?

The old advertisements for the Ford Motorsport version of them in aluminum claimed an immediate 40hp increase over a stock head. Never specified what year stock head, but that was the common number used back then.
You might not feel a 10hp increase by the seat of your pants, but it's hard to hide a 40hp increase!

I have P heads on my '68 and the entire engine is stock Explorer. Cam, exhaust, induction and virtually all smog components intact.
It feels like it could run circles around any other stock Bronco I've driven from back in the day. But that's not completely apples-to-apples either, because this one is geared completely differently too, in the tire size/gear ratio department.

I’m reading mixed reviews and looking for more real world experience. Looking at a stock 302, RV cam and the GT40p Heads.

Mixed reviews is what you get. Always.
Everyone has different ideas of what works, different levels of experience, and even different levels of sensitivity to such things.
And that's not including the huge number of differences in Broncos and driving habits.

Good luck though. Personally I think they're worth it if you're not ready to go with an aluminum aftermarket cylinder head at this point.

Paul