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  #46  
Old September 13th, 2017, 08:00
Green XJ Jeep Green XJ Jeep is offline
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Re: Edelbrock head ported

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Originally Posted by Fosters View Post
Why on earth did Chrysler think this was a good idea, I don't know. One side of the engine bay is completely empty... while the other is busy baking the intake with the exhaust. Any such thing in the works?
Chrsyler didnt design it if they had it would have been slanted over 45degrees
The motor itself was designed in the 1960's and needed the exhaust heat to keep the fuel in suspension
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  #47  
Old September 13th, 2017, 20:02
tech1001 tech1001 is offline
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Re: Edelbrock head ported

I hate this a can not see any of these pictures , no matter what I do the pictures will not show up for me .
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  #48  
Old September 13th, 2017, 21:23
Fosters Fosters is offline
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Re: Edelbrock head ported

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Originally Posted by cal View Post
They did it for the same reason every one else does it - push rods.

To do a crossflow head you need to be running an overhead cam. That drastically changes the engine design and just isn't necessary for the engine in the environment it was designed for.

Its also why you won't see anyone do it for the aftermarket.
Every V8 out there has intake on the inside along with the pushrods, and exhaust on the other/out side...

well, except my powerstroke, that's backasswards.

Quote:
Originally Posted by Green XJ Jeep View Post
Chrsyler didnt design it if they had it would have been slanted over 45degrees
The motor itself was designed in the 1960's and needed the exhaust heat to keep the fuel in suspension

Good point, forgot about AMC... And yeah, fuel heat up was my original thought too... but you gotta say, from the early 90s till 2006, they could have mixed it up a lil'...

These guys cracked me up with the heating of the intake/air...
https://www.youtube.com/watch?v=LPnoRu50s9M
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  #49  
Old September 14th, 2017, 07:36
Green XJ Jeep Green XJ Jeep is offline
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Re: Edelbrock head ported

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Originally Posted by Fosters View Post
Good point, forgot about AMC... And yeah, fuel heat up was my original thought too... but you gotta say, from the early 90s till 2006, they could have mixed it up a lil'.
No need, it it did its job exceptionally well and in my opinion is a way better motor than than the v6 that replaced it.
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  #50  
Old January 18th, 2018, 15:50
The_Punisher The_Punisher is offline
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Re: Edelbrock head ported

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Originally Posted by yossarian19 View Post
at .50 lift it's 5% difference between the 7120 and the ported Eddie. Biggest cam I can find for the 4.0 is .53 lift on intake, where its closer to 6%.
I don't see spending $1500 or so for that last few percent, myself, but it's a cool race part? Then again, with an aluminum head you can get a little more compression / ignition advance out of it without detonation. Might be a bigger upgrade than the flow numbers alone suggest.
I didn't realize until recently, all of the major cam manufacturers don't even charge you more $$$ for a 100% custom camshaft!

So off the shelf grinds might not be available to take advantage of such killer flow at high lift values, but it only takes a phone call to a cam manufacturer.

I'm also currently the owner of the exact head in this thread. My engine specs are:

-4.7L
-11:1 static CR
-Harland sharp roller rockers
-The ported head in this thread + matched intake
-70MM throttle body
-Doug thorley header, ported a bit by me to help the exhaust ports match up a bit better. 3" outlet/open no muffler or cats
-Custom cam from comp cams. Something in the neighborhood of .590 intake, .600 exhaust, duration @ .050 of 224 int/230 exh on a 113 LSA. This is a rough estimate after talking with them. Not sure on final numbers, might be a little less duration.

I'm honestly striving for 350 HP on 93 octane.
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  #51  
Old January 26th, 2018, 22:57
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yossarian19 yossarian19 is offline
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Re: Edelbrock head ported

350 horse from 287 cubes is about 1.22 horse per cube.
For perspective, that's the same ratio as a Chevy 350 making about 425 horsepower.
I don't know the I6 well enough to say. Sounds doable. It's going to take 330 ft lbs at 5600 RPM, which sounds ambitious. Post burnout vids if you do it!
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  #52  
Old January 27th, 2018, 20:59
The_Punisher The_Punisher is offline
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Re: Edelbrock head ported

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Originally Posted by yossarian19 View Post
350 horse from 287 cubes is about 1.22 horse per cube.
For perspective, that's the same ratio as a Chevy 350 making about 425 horsepower.
I don't know the I6 well enough to say. Sounds doable. It's going to take 330 ft lbs at 5600 RPM, which sounds ambitious. Post burnout vids if you do it!
Agreed. I break it down to HP per cube also. A better perspective is actually a stroked 350. If you chop 2 cyl off of a 383 SBC its 287 CI.

I ordered my Cam. I changed directions a bit. I got a custom Solid flat tappet from Lunati.

Lift with 1.65's: .546 intake/.571 exhaust
Duration @ .050 233 intake/241 exhaust
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