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Quick question, does anyone know for sure if the upper intakes are interchangeable between a 302 EFI and 351 EFI?

Thanks in advance,

Brian
 

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not the same shape ports... but interchangeable
 

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They will bolt together, it just takes some sweat equity to make the ports match. I'm in the middle of porting a 351 lower to match a 302 upper. I've got the front 4 done (1,2,5,&6). It gets a little narrow in places, but there should be more than enough for a good seal between the two.

Pics to follow after I'm done!
 

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I am running a ported 351W lower and a 302 upper.... works AWSOME!!!!
 

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Palehorse said:
Quick question, does anyone know for sure if the upper intakes are interchangeable between a 302 EFI and 351 EFI?

Thanks in advance,

Brian
Well, that sucked. Four different answers from four different people. So I think the true answere is that while its not a simple interchange, it can be done if you are willing to put in a little time and patience with a die grinder.
 

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why are you asking if they fit?? what is your plan??
 

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Satyr of the Midwest
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I'm not claiming to know this off-hand (more than likely because I just use whatever parts are made for the particular engine I'm working on, but anyhow...), but I'd think that a 351W plenum would be too wide on a 302, and vice versa, narrow. Have you ever looked at the lowers for both side by side? There's a huge difference. I'd say if you're looking for power from your intake manifold, find an aftermarket one that will actually flow some REAL amounts, like an Edelbrock or a Trick Flow.
 

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Charlie don't surf..
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This is a 351 lower intake (oval)


The 302 is sqaure. Sure you could probably do a s**tload of work to get them to match, but the simple answer is no, they will not just bolt together.
 

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Back in the day before the aftermarket exploded for the fuel injected small block Ford the hot ticket was to get an intake from a 302 truck engine and make it work in the Mustang. The lower flows awesome (don't remember the numbers) and people were modifying the upper to meet their needs--hotrodding at its' finest!

If you look at the Saleen/Vortech and Holley intakes for the 5.0 fuelie you'll notice a STRONG resembelance to the 5.0 truck lower. That's because it is! They made new uppers to raise the powerband and be a direct bolt-on for the Mustang.

So taking the time to port a 351 LOWER to mate up with a 302 UPPER is a worth-while venture in my books. The 302 truck intake has proven itself to be an outstanding performer. I'm not saying that I'll have the EXACT port shape at the middle of the runner, but it'll whoop ass on a stock 351 intake--without spending over $500 on an Edelbrock intake!!:rockon

Pics and seat-of-the-pants performance report to follow after I get my new intake setup installed (hopefully in about a week). I have some ideas and tricks that I'll talk about at that time as well. Then we can hopefully put this issue to rest once and for all :box0715: and we can get back to more important things :drinkbud !

SigEpBlue said:
I'm not claiming to know this off-hand (more than likely because I just use whatever parts are made for the particular engine I'm working on, but anyhow...), but I'd think that a 351W plenum would be too wide on a 302, and vice versa, narrow. Have you ever looked at the lowers for both side by side? There's a huge difference. I'd say if you're looking for power from your intake manifold, find an aftermarket one that will actually flow some REAL amounts, like an Edelbrock or a Trick Flow.
 

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Ex Navy Nuke
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Between the gazillion hours it would take to port one of those and all the bits you're gonna waste doing it(aluminum really clogs up the bits) it's worth it to spend the money on an Edelbrock. I got my Edelbrock on ebay for a little over $300 and it looked like new.
 

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Don't get me wrong, I know that the Edelbrock is the better performer. With the raised lower allowing the ports to be moved forward for a straighter shot at runners 1 and 5 it's a no brainer. All I'm saying is that this will make for better performance than having a stock 351 intake without spending $500+.

When I started I could barely see through runners 1 & 5, now I can see roughly 75-85% through the port. My total investment will be less than $150 (with carbide bits made for aluminum so they don't clog) and a few hours with the die grinder. I would love to have an Edelbrock intake, but after the lift, rims, tires, and gears the wife won't let me.
 

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The Anti Yam!
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This is literaly like forcing a square peg in a round hole.

But hey, if youve got the time and the patience then go for it. :thumbup

Persionaly if it was me I would just be searching for a cheape used Edelbrock 5.8 truck performer, 5.8 Car performer, or a used GT-40 off of a 1st gen L-Truck.

I'v seen them go for as little as $200.00
(but thats fairly rare)
 

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I've got a ported 351 GT-40 lower W/Cobra upper on eBay right now. I was going to use it but I didn't know what was involved in getting the car style t-body to work on the Bronco.

It really isn't that bad to port using carbide tipped bits made for aluminum, they don't clog up and cut really well!
 

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The Anti Yam!
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p-351 said:
I've got a ported 351 GT-40 lower W/Cobra upper on eBay right now. I was going to use it but I didn't know what was involved in getting the car style t-body to work on the Bronco.
E4OD will need a lightning throttle bracket, AOD will need a 302 car bracket (non Mustang) I would imagine a C-6 could use the AOD bracket and a manual can use any bracket.

RLKBOB's E4OD Lightning bracket



Here is Fireguy50's home maid bracket for an AOD.


I'll be using the bracket from a car when I do mine.
 

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What did switching to a Performer style intake do for your low-end torque? I know that it'll make more power on the top-I'm just curious if you noticed any different powerband characteristics.

--I also thought that you were talking their truck upper intake, not the car upper when you were talking about the Edelbrock intake:doh0715:
 
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