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Discussion Starter #1 (Edited)
I have a 96 351w roller motor. I have ported Gt40 heads and a lightning intake manifold. Stan's tri y headers to a 3" y pipe.

I've seen anywhere from 20-40 hp gains. The combination I recreated is essentially a lightning bronco. Lightnings had 240hp factory.

My current dyno with headers and tune only is below. 194/313 at the wheels.
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Discussion Starter #2
I'm speculating 35 hp with the ported heads, tubular intake, and retune.
 

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Did you get the heads back from Dean? Did give flow results?

With ported gt40s, you should see a bit more HP than the lightning.
 

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Discussion Starter #4 (Edited)
Did you get the heads back from Dean? Did give flow results?

With ported gt40s, you should see a bit more HP than the lightning.
Yup. This is what he said. The flow numbers aren't as good as what I was expecting he used a 1.9/1.5 valve. The exhaust valve is smaller than stock so I was pretty confused but he was very confident in his valve choice. He said these would be like an AFR 155?
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Yup. This is what he said. The flow numbers aren't as good as what I was expecting he used a 1.9/1.5 valve. The exhaust valve is smaller than stock so I was pretty confused but he was very confident in his valve choice. He said these would be like an AFR 155? View attachment 173000
Compare those to the AFR165s and You'll find that those flow pretty comparable until .400" lift. The 1.5 exhaust valve will help with velocity. My 300 is using a 1.6 and it has larger cylinders than yours
 

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I am interested in the final results. Good luck.

tim
 

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How do you put a smaller valve in? Wouldn't that just mean less seat overlap? The exhaust valves have wide seats, so maybe the thinking is, they don't need that much overlap in the first place, so a smaller valve will allow more air to get around it without opening up the seat? That's all I've got...

I'd be curious to see pictures of the porting job. The hand written notes aren't the easiest to visualize, but they read like maybe he didn't port very aggressively, which could explain the "not much gain." Then again, 20-25 HP from porting, if that's what he means, is probably reasonable. With the jump up from E7's, that's in the 40 HP range, which is all you'd expect from ported GT40's.
 

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How do you put a smaller valve in? Wouldn't that just mean less seat overlap? The exhaust valves have wide seats, so maybe the thinking is, they don't need that much overlap in the first place, so a smaller valve will allow more air to get around it without opening up the seat? That's all I've got...

I'd be curious to see pictures of the porting job. The hand written notes aren't the easiest to visualize, but they read like maybe he didn't port very aggressively, which could explain the "not much gain." Then again, 20-25 HP from porting, if that's what he means, is probably reasonable. With the jump up from E7's, that's in the 40 HP range, which is all you'd expect from ported GT40's.
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^ That picture doesn't give any indication of the porting, but a couple thoughts from what I can see:

1) He shaved down the spark plug area, which the write-up I've seen recommended against.

2) The chambers are "polished" (and the valves slightly un-shrouded), which isn't thought to have much benefit.

3) Maybe my eye can't discern a 0.04" difference, but the exhaust valves sure don't look like they're skinnied up in their seats. It does show how little space is available for going oversized on both valves, though. Do you have some calipers for measuring how much gap is there with 1.90/1.50? And for that matter, confirming that they're actually 1.50?
 

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Remember that number of the Lightning is brake / flywheel horse, its not rear wheel horse. So your 194 to the wheels is round bout right for 240 at the flywheel. Might do better with a slightly better tune to pick up a few more horses. Stick or auto there will be a 10 to 20% loss for drivetrain for vehicles.
 

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See comments after each statement.

^ That picture doesn't give any indication of the porting, but a couple thoughts from what I can see:

1) He shaved down the spark plug area, which the write-up I've seen recommended against.

Doesn't appear to much was done around the sparkplug area no shinny surfaces there.

2) The chambers are "polished" (and the valves slightly un-shrouded), which isn't thought to have much benefit.

The chambers do not appear to be polished anywhere except around the valves where they were unshrouded, like you said and that is only machining marks on the surface not polishing marks.

3) Maybe my eye can't discern a 0.04" difference, but the exhaust valves sure don't look like they're skinnied up in their seats. It does show how little space is available for going oversized on both valves, though. Do you have some calipers for measuring how much gap is there with 1.90/1.50? And for that matter, confirming that they're actually 1.50?

The stock size for Ford exhaust valves are either 1.46" or 1.54" I agree with you here.
 

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Doesn't appear to much was done around the sparkplug area no shinny surfaces there.

The chambers do not appear to be polished anywhere except around the valves where they were unshrouded, like you said and that is only machining marks on the surface not polishing marks.
They look smoother than I'm accustomed to, which is why I said "polished" not polished...referring to the approach, not the end result. ;) Maybe it's just the lighting and focus messing with my eyes, though.

Edit: I copied the image and viewed it full-size, and with the extra clarity, I think you're right.

The stock size for Ford exhaust valves are either 1.46" or 1.54" I agree with you here.
It's 1.54 on the GT40s.
 

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Gotta find time to install them and someone to help. Goes a bit beyond my technical skills to tackle it solo.
Understand that and no shame in it either. My issue is I don't have a "place" and would be super reluctant to even start a project like that outdoors. But, it should not be too bad. I hope the results are worth the effort.

Please keep us updated.

tim
 

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How do you put a smaller valve in? Wouldn't that just mean less seat overlap? The exhaust valves have wide seats, so maybe the thinking is, they don't need that much overlap in the first place, so a smaller valve will allow more air to get around it without opening up the seat? That's all I've got...
The smaller valve does allow more air to flow around it in this application. .040" is indiscernible to the naked eye without a visual comparison. The 4 angle valve job will also help a lot.

The ol boy who did the work knows what he is doing. I bought a set of heads from him for my 351 almost 15 years ago. He also helped me get it running and installed gears for me.

I see all factory cast metal around the plugs.

Pushrod bosses were shaped on the proper areas. Im not sure what he means by biased the Exh under the seat. Maybe some undercutting on the top of the valve.

Head porting is a science. Its much easier to destroy flow than to improve it. Another forum im a part of has a 500 post thread following the adventures of creating not one, but three different levels of replacement head for the 300-6. Its very informative and way about my level of skill. When i had my 300 built by a different guy, he was adamant about him not porting the head because he didnt have the knowledge for a 300 or a flow bench to test.

I need to stop buying guns and stuff(!!!) and have Dean do my spare 300 head before he cant anymore. Last time i talked with him, he was 70 and had been going through health issues.
 
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Discussion Starter #16
The smaller valve does allow more air to flow around it in this application. .040" is indiscernible to the naked eye without a visual comparison. The 4 angle valve job will also help a lot.

The ol boy who did the work knows what he is doing. I bought a set of heads from him for my 351 almost 15 years ago. He also helped me get it running and installed gears for me.

I see all factory cast metal around the plugs.

Pushrod bosses were shaped on the proper areas. Im not sure what he means by biased the Exh under the seat. Maybe some undercutting on the top of the valve.

Head porting is a science. Its much easier to destroy flow than to improve it. Another forum im a part of has a 500 post thread following the adventures of creating not one, but three different levels of replacement head for the 300-6. Its very informative and way about my level of skill. When i had my 300 built by a different guy, he was adamant about him not porting the head because he didnt have the knowledge for a 300 or a flow bench to test.

I need to stop buying guns and stuff(!!!) and have Dean do my spare 300 head before he cant anymore. Last time i talked with him, he was 70 and had been going through health issues.
Guns are addictive. I need to go to the range and shoot my pew pew. I trust what Dean did. He also told me not to waste my money porting my ls3 heads because they're so good. I can give up 20 hp to save $700.

He did seem intrigued by porting the 300 head because he hasn't done one before.
 

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He did seem intrigued by porting the 300 head because he hasn't done one before.
Most certainly! He is an old school tinkerer and loves a challenge. I remember the sheer amount of valves and springs he had on the walls was incredible.

My goals for that 300 head are a bit different than your GTs. I want him to squeeze every bit of flow out of it, even if it means some 'next level' work like epoxying and such to really change the shape of the runners. I dont necessarily need the streetability of the safe porting limits.
 

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Discussion Starter #18
Most certainly! He is an old school tinkerer and loves a challenge. I remember the sheer amount of valves and springs he had on the walls was incredible.

My goals for that 300 head are a bit different than your GTs. I want him to squeeze every bit of flow out of it, even if it means some 'next level' work like epoxying and such to really change the shape of the runners. I dont necessarily need the streetability of the safe porting limits.
You should throw a turbo on it.
 

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You should throw a turbo on it.
Too much compression. Im at 9.75 to 1. Id have to swap pistons out. I have contemplated it, and that was the advice given to me by turbo 300 pros.

Though I do have a spare block in the van that my spare head came from. Im fighting between that with a turbo or the 351 already in my trail truck project. Leaning towards the 300 for it with a c6 and 205/203 doubler. I have a pair of turbos already, one from a 6.0 or 7.3 PSD and one from an International DT466.
 
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