347 EFI Low Power

Liberty is just a jobber parts house from the Philly area, hence the name.. You can order Pac valvetrain thru them if you wanted and the heads bare or complete plus you can swap springs without pulling the heads pretty easy.. I would ask the builder how he ordered them and what springs it used either way. The as cast port tends to be in the 250cfm range on most benches, its the exhaust that's weak, a box stock edelbrock intake is like 225 cfm tops, a better intake or even porting would help more then a t body or intake pipe. My heads where like 286/188 in my lift range and I'm no porter. I honestly expected to run over the crank in that car but haven't hurt it yet. Rev hang would be in the tune, fords old IAC ain't the best set up.
Would I need to port the upper and lower or just the lower where it bolts to the heads?
 
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A custom cam from Ed at Flow Tech would help along with a better flowing intake like the Holley Systemax. But like pretty much all of us money is a huge factor. If your budget allows for it I would contact Ed. He is currently making a killer Systemax intake for me.
 

TOOLOW91

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Shorties, I heard long tubes are a pain on the aod
Yeah they are . I had RCI who is no longer doing them build me a set . I would try and find a set of big shortys. If you do find long tubes the problem is that you’ll have to have or be able to build a custom x pipe because finding one is tough .

Here’s another question that no one ever asks usually … what mufflers are on it ?

I have seen as much as 40 rwhp from getting rid of restrictive mufflers
 
Yeah they are . I had RCI who is no longer doing them build me a set . I would try and find a set of big shortys. If you do find long tubes the problem is that you’ll have to have or be able to build a custom x pipe because finding one is tough .

Here’s another question that no one ever asks usually … what mufflers are on it ?

I have seen as much as 40 rwhp from getting rid of restrictive mufflers
I have cherry bomb vortex on it, most likely gonna get changed soon because they sometimes rub my driveshaft.
 

TOOLOW91

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I really like my Black Widow Venom 250 mufflers. Straight through design with no packing.
This - pypes race pros , borla xr1 , dyno max ultra flow etc

I run the ultra flows on my mustang and the pypes on my 66 belair .

I’m not sure what style the ones you have on there now are but when you’re looking for every last hp I have seen popular mufflers give up a good bit .

Now that you have your answers it’s time to do some homework . Starting with that damn converter LOL
 
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This - pypes race pros , borla xr1 , dyno max ultra flow etc

I run the ultra flows on my mustang and the pypes on my 66 belair .

I’m not sure what style the ones you have on there now are but when you’re looking for every last hp I have seen popular mufflers give up a good bit .

Now that you have your answers it’s time to do some homework . Starting with that damn converter LOL
Yeah so I am going to just leave the heads as is cause I do not want to take those off. I did call the guy who built the engine and he said he puts his own valve train on, not from liberty. I will get my intake ported so it flows at or above 250cfm to match the heads. From what I'm seeing flow wise, my 70mm TB is plenty. I will definitely change my converter at some point and I will most likely get 1 3/4 shorties
 
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96pushrod

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Those numbers honestly fall on line with what I’d expect from China cylinder heads and a box stock performer rpm. The stock performer rpm runners are tiny, and will definitely limit power, the heads will be the next restriction, but not as bad.

You’ll spend almost as much having the intake ported as buying another one, but at least you know it’ll fit.

Long tube headers almost always make more power than short as well, but the aod complicates things.
 
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General karthief

wonder how much it would cost to ship you a pair
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Let's take the header debate a step farther, with the cam, head and intake he has header choice is not going to add much, just stick with the 1 5/8" shorties you got, you may gain a few hp points with long tubes,like maybe 10hp, but the biggest gain, although still small, will be the low end torque points, and going to a bigger tube size likely will kill torque more without adding hp.
All this points to the importance of planning parts selection with how the car will be driven most of the time.
If this were my car with the listed parts/pieces there now and looking for a little more guts I would research the valve springs to see if they are matched to the cam, add a shift kit to the trans, some intake port work, and look at my timing, I also prefer long tube headers for the low end torque on the street but it's a personal preference thing too.
These are just my opinions and not based on any real mechanical experience.
 
Let's take the header debate a step farther, with the cam, head and intake he has header choice is not going to add much, just stick with the 1 5/8" shorties you got, you may gain a few hp points with long tubes,like maybe 10hp, but the biggest gain, although still small, will be the low end torque points, and going to a bigger tube size likely will kill torque more without adding hp.
All this points to the importance of planning parts selection with how the car will be driven most of the time.
If this were my car with the listed parts/pieces there now and looking for a little more guts I would research the valve springs to see if they are matched to the cam, add a shift kit to the trans, some intake port work, and look at my timing, I also prefer long tube headers for the low end torque on the street but it's a personal preference thing too.
These are just my opinions and not based on any real mechanical experience.
The engine builder said he did his own valve train not liberties so I'm going to assume it's good. I have ordered a valve body already where I can hold 1st, 2nd and 3rd. If I can get intake port work done for 350 or less it's probably worth it because I picked the intake up for 400.
 
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96pushrod

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Let's take the header debate a step farther, with the cam, head and intake he has header choice is not going to add much, just stick with the 1 5/8" shorties you got, you may gain a few hp points with long tubes,like maybe 10hp, but the biggest gain, although still small, will be the low end torque points, and going to a bigger tube size likely will kill torque more without adding hp.
All this points to the importance of planning parts selection with how the car will be driven most of the time.
If this were my car with the listed parts/pieces there now and looking for a little more guts I would research the valve springs to see if they are matched to the cam, add a shift kit to the trans, some intake port work, and look at my timing, I also prefer long tube headers for the low end torque on the street but it's a personal preference thing too.
These are just my opinions and not based on any real mechanical experience.
It may be an unpopular opinion, but I wouldn’t bother with anything but a long tube, if I’m buying new. They just always pick up everywhere.

Op: which shorty headers are on the car now? Like which brand?
 
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It may be an unpopular opinion, but I wouldn’t bother with anything but a long tube, if I’m buying new. They just always pick up everywhere.

Op: which shorty headers are on the car now? Like which brand?
I think they are BBK or something of similar quality, nothing crazy.

Just a thought, I'm looking at my torque curve and it looks relatively flat throughout, if I went with 1 3/4 my peak torque would be at 4400 rather than 3900, a little bit of a stretch but it almost looks like my area under the torque curve would be better if I did that so it doesn't fall off after 4k.
 

96pushrod

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I think they are BBK or something of similar quality, nothing crazy.

Just a thought, I'm looking at my torque curve and it looks relatively flat throughout, if I went with 1 3/4 my peak torque would be at 4400 rather than 3900, a little bit of a stretch but it almost looks like my area under the torque curve would be better if I did that so it doesn't fall off after 4k.
If you cut that :poo:ty reduced ball and socket collector bbk uses and put something better on it would probably pick up, but probably not much with the intake it has now.

Not that ball and socket is bad, but the ones bbk uses taper down to around 2.2in.
 
If you cut that :poo:ty reduced ball and socket collector bbk uses and put something better on it would probably pick up, but probably not much with the intake it has now.

Not that ball and socket is bad, but the ones bbk uses taper down to around 2.2in.
How about equal length headers? I kind of want to replace these headers because I'm pretty sure there is a pinhole, I changed gaskets and there is still a leak.
 
How about equal length headers? I kind of want to replace these headers because I'm pretty sure there is a pinhole, I changed gaskets and there is still a leak.
Shorty's are are usually no more than 4 to 6 hp of an improvement over stock manifolds. Go with longtubes and better heads. The Chinesium heads are making about what I would expect with the rest of the combo. A set of AFR's and a custom cam or the Comp XFI 236 should get you closer to where you want to be.
 
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Shorty's are are usually no more than 4 to 6 hp of an improvement over stock manifolds. Go with longtubes and better heads. The Chinesium heads are making about what I would expect with the rest of the combo. A set of AFR's and a custom cam or the Comp XFI 236 should get you closer to where you want to be.
I'm fairly confident that this setup will make 340-350 to the wheels after getting a better intake. I don't want to go through troubles with long tubes with my aod
 

96pushrod

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How about equal length headers? I kind of want to replace these headers because I'm pretty sure there is a pinhole, I changed gaskets and there is still a leak.
Equal length short tubes won’t net you anything over regular short headers.

Bbk makes a set of long tubes that are meant to fit an aod.

Either way, there will be good gains even if you leave the short tubes after the intake is ported by someone competent.
 
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