5.4 3v short block

2003cobra22

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Im getting parts together for a 5.4 short block, I already have a set of Oliver 5.4 Billet Connecting Rods #F6657MDUL8 and the FRPP Cobra Jet Crankshaft. Going to use a iron truck block and have a machine shop do the assembly, don't have pistons yet need advice of which to go with? Looking for close to stock CR setup with .020" Over Bore (3.572") that i could run NA or add some boost later on and have some longevity. Motor is street use mostly
 
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408Stang

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Im getting parts together for a 5.4 short block, I already have a set of Oliver 5.4 Billet Connecting Rods #F6657MDUL8 and the FRPP Cobra Jet Crankshaft. Going to use a iron truck block and have a machine shop do the assembly, don't have pistons yet need advice of which to go with? Looking for close to stock CR setup with .020" Over Bore (3.572") that i could run NA or add some boost later on and have some longevity. Motor is street use mostly
Contact Gibtec Pistons in Denver, CO. 303-243-3340 Ask for Nick. They can make you custom billet pistons in any CR you want, ANY size you want, any configuration you want, etc.... Just name it they can do it. For example, If your block only needs a hone they can build a piston to fit it exactly, down to . 001 increments, rather than you having to go 10, 20, or 30 over.


Set if 8 should run you about $1k... (including Total Seal rings and .200 wall pins) Could be higher as you start adding ceramic top coatings, coated skirts, offset pins, anti-flutter grooves, etc.
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Sent from my A0001 using Tapatalk
 

2003cobra22

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Those look nice, might have to weigh paying some extra money for a custom piece over an off the shelf piston

Havent gotten a block yet, would like to keep the stock bore but not sure what kinda shape a seasoned 5.4 iron block might be in
 
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A John In NJ

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Those look nice, might have to weigh paying some extra money for a custom piece over an off the shelf piston

Havent gotten a block yet, would like to keep the stock bore but not sure what kinda shape a seasoned 5.4 iron block might be in

You need to talk to the master.... You need yourself some BruceH knowledge...

Contact or look up BruceH and his many topics of conversation. After you've read all of it... You may be surprised at what you come up with:sunot:
 

2003cobra22

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what u going to do for intake manifold?

Gonna look around for used MMR or JPC sheet metal piece, see them pop up in classified sections Im in no hurry. Other option buy a more common 4.6 sheet metal intake cut in in half have my buddy help fabricate one.
 

2003cobra22

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Using a 2007 5.4 block from an f150, debating going forward to build the motor for NA or some boost down the road. If I go NA route I would overbore .030 and run higher compression. Those who have done 5.4 builds looking for opinions
-heads are gonna be CNC ported 3v's
-gonna use a sheet metal 4.6 intake cut it in half and weld, anyone who has done this does increasing the plenum volume but not the runners have any negatives
-exhaust I'm using a set of 4.6 3v longtubes, cut and lengthen to get the fitment
 

95ragtop

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Using a 2007 5.4 block from an f150, debating going forward to build the motor for NA or some boost down the road. If I go NA route I would overbore .030 and run higher compression. Those who have done 5.4 builds looking for opinions
-heads are gonna be CNC ported 3v's
-gonna use a sheet metal 4.6 intake cut it in half and weld, anyone who has done this does increasing the plenum volume but not the runners have any negatives
-exhaust I'm using a set of 4.6 3v longtubes, cut and lengthen to get the fitment

For the long tubes, they may fit. I helped a guy with a 5.4 3V swap and he used 4.6 long tubes without any modifications.

I have heard that 30 over on mod motors isn't recommended due to the bore spacing. I'm not an engine builder, so if someone with more knowledge than me says it's good then rock it.

I figure the heads wouldn't hurt as the 50 extra cubes are going to need the airflow. I am assuming you're swapping in some cams?

For the intake you may be able to research what 4.6 to 5.4 DOHC guys did and how the extra plenum volume affected them. I think the extra volume will work well since you have the added displacement.

Do you have an ideal rpm in mind? Have you looked at what Spyder did about 5 years ago with his 5.4 3V? He did an all out build with it. Solid roller and E85 plus spinning it to the moon. Made somewhere around 480 rwhp with an auto.
 

Speedboosted

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.030" is the max I'd want to go on an application under 800 whp or so. Anything greater (bore or power) and you really start to weaken the cylinder. Run as small overbore as necessary for the block. I don't see there being any power increases between .010" to .030".

5.4 iron blocks are especially weak when deeply bored.
 

2003cobra22

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For the long tubes, they may fit. I helped a guy with a 5.4 3V swap and he used 4.6 long tubes without any modifications.

I have heard that 30 over on mod motors isn't recommended due to the bore spacing. I'm not an engine builder, so if someone with more knowledge than me says it's good then rock it.

I figure the heads wouldn't hurt as the 50 extra cubes are going to need the airflow. I am assuming you're swapping in some cams?

For the intake you may be able to research what 4.6 to 5.4 DOHC guys did and how the extra plenum volume affected them. I think the extra volume will work well since you have the added displacement.

Do you have an ideal rpm in mind? Have you looked at what Spyder did about 5 years ago with his 5.4 3V? He did an all out build with it. Solid roller and E85 plus spinning it to the moon. Made somewhere around 480 rwhp with an auto.

Overbore would only be if I decide to keep the motor an NA only build since the spacing is already narrow between cylinders. Cams, valve train, etc will compliment the heads and setup. Im sure the 4.6 3v headers will run into some fitment issue due to the taller deck 5.4 block. Read some of the Spyder and Flapjack threads about there 5.4 3v builds, they used the MMR or JPC intake manifolds but those pieces are over priced for my taste. MMR makes adapter plates for the 5.4 4v heads to use the coyote intakes but no luck for 3v applications. I was looking at the Holley sniper manifold for the 4.6 3v which i can cut in half then weld the gaps. RPMs like to see up to 7k
 

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