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Hello all, I've decided I'm going to build a 557 stroker to put into my 1975 F150 Ranger XLT.

Goals for this truck: Not going to be a daily driver, but would love for it to be reliable, and streetable at about 650hp on pump gas. Don't plan on towing anything with it, but may put stuff in the bed of the truck from time to time (dirt bikes most likely). The truck will have an Auto transmission in it, not sure what rear end ratio I'll end up with, or tire size.

My biggest question is what is a good Cam to pair with this motor to get what I want. I'm fairly set on getting a hydraulic roller cam.

Specs:

Heads: AFR 315cc BBF Bullitt 14 Degree Cylinder Heads 3835
https://www.summitracing.com/parts/afr-3835/overview/make/ford

Rotating Assymbly: Scat Engine Rotating Assemblies 1-47618BI
https://www.summitracing.com/parts/sca-1-47618bi/overview/make/ford

Headers:
Hedman Elite Heavy-Duty Headers 89468
https://www.summitracing.com/parts/hed-89468/overview/make/ford

Rocker Arms:
Scorpion Race Series Rocker Arms 1023 (1.73:1 ratio)
https://www.summitracing.com/parts/scc-scp1023/overview/make/ford

Intake/Carb: Open to suggestions on this
Summit Racing® Tunnel Ram and Carburetor Pro Packs 03-0188
https://www.summitracing.com/parts/cmb-03-0188

Cam: I know this isn't a hydraulic roller, but this is what I have selected so far.
COMP Cams Xtreme Energy Camshafts 34-773-9
https://www.summitracing.com/parts/cca-34-773-9



I am open to suggestions on anything on this build, as I haven't purchased anything yet.

Any help would be greatly appreciated!

Thanks
 

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At 557 cubes and 650 hp levels, two 600 Holleys that come in the carb/manifold kit are not big enough, barely big enough for a 429 or 460....you need twin 750's at least.

Cam is in the correct size range anyway, now just find something like it in a hydro roller if that is what you want.
Remember that a similar spec Hydro roller will be equal with about 8-10° less duration, as it doesn't have a lash ramp to take up before the valve starts moving like a solid profile does.

Engine that big on cubes really need a bigger header primary tube too, 2" or 2-1/8"....the 1-3/4" I use on my 500 hp small blocks ;)
Full length header would be better too.
 

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Discussion Starter #3
At 557 cubes and 650 hp levels, two 600 Holleys that come in the carb/manifold kit are not big enough, barely big enough for a 429 or 460....you need twin 750's at least.

Cam is in the correct size range anyway, now just find something like it in a hydro roller if that is what you want.
Remember that a similar spec Hydro roller will be equal with about 8-10° less duration, as it doesn't have a lash ramp to take up before the valve starts moving like a solid profile does.

Engine that big on cubes really need a bigger header primary tube too, 2" or 2-1/8"....the 1-3/4" I use on my 500 hp small blocks ;)
Full length header would be better too.
Maybe I was doing the calculations wrong, but using a CFM calculator online, I figured I needed about 1200CFM. But I guess it wouldn't hurt to get 2 750's and jet them down if need be.

And I think my issue with the headers was finding something that fit a 1975 F150. If there's full length headers in 2" to 2-1/8" that fit I'm all for it. But thinking about it, I'm not really sure why I thought 1-3/4" was going to be big enough.
 

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Yeah, the vehicle platform your putting it in isn't the most common performance chassis for Ford guys :D
Did you try L&L Products for the headers? They used to have several big tube sets for that chassis, at least I think they did.

On a tunnel ram with two carbs, the signal is split between them, so they will rarely reach their peak flow rating without becoming a restriction to power. That's why they use two that together would seem way bigger than a single carb calculator would show you needing.
 

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But I guess it wouldn't hurt to get 2 750's and jet them down if need be.
I used to know another fellow who used to say the same thing, about "jetting down his carb" that was too large for the application.

No matter the cubic feet per minute air flow capacity of a carburetor, it cannot be "jetted down" to a smaller capacity. Jetting it down will lean it out, changing the relationship of air to fuel, but the only way to reduce the capacity of the carburetor would be to sleeve the bores to make them smaller and I don't know that I have ever known of anyone to do that.

What static compression ratio are you planning on using in this motor? What fuel will you run it on?

.
 

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Street able and around 600hp?


521.

Been done many times before you can pick from list of build sheets depending on your chosen compression ratio.
I would run it in the 9.6 to 10.3 range to have low rpm street able torque yet still run on pump gas.

Building a 521 allows for a much more less extreme parts to be used like aftermarket throttle body fuel injection and a common fuel pump. Around 2500-3000 rpm your still making some nice torque and running a good idle.


If your heart has always been set on a 557 and you have the budget to drop 15-20 into the engine as well as the additional behind the engine then go for it.
But for a street friendly build a 521 checks many of your boxes while being less aggressive then a 557 build in many aspects.
 

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https://www.460ford.com/forum/37-engine-tech/[email protected]

Here is an example of a street build using the AFR heads that makes almost 750 hp. 650 is easily done. Follow the link in the OP's signature for more build examples.

Hydraulic roller can be problematic on a BBF due to push rod length. You can probably make 650 HP with a HFT cam at those cubes with those heads for less money.

If hood clearance is of any concern use a Torker II single plane intake.
 

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Hydraulic roller can be problematic on a BBF due to push rod length. You can probably make 650 HP with a HFT cam at those cubes with those heads for less money.
Tommy, can you please explain the pushrod length problem with using a hydraulic roller cam?

Also, I would like to suggest that you use the full names of items for the benefit of the new fellows on the board who are trying to learn. I and most of the old timers on here know that BBF is big block ford and HFT is hydraulic flat tappet, but youngsters might be put off and confused by the initials. Also, if you are going to suggest a flat tappet cam, you might also explain how problematic they are in today's roller tappet world.
http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks

Thank you.
 

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Tommy, can you please explain the pushrod length problem with using a hydraulic roller cam?

Also, I would like to suggest that you use the full names of items for the benefit of the new fellows on the board who are trying to learn. I and most of the old timers on here know that BBF is big block ford and HFT is hydraulic flat tappet, but youngsters might be put off and confused by the initials. Also, if you are going to suggest a flat tappet cam, you might also explain how problematic they are in today's roller tappet world.
http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks

Thank you.
The 385 series BBF is a canted valve design. The pushrod seat in the hydraulic roller lifter is about .650 taller. This changes the pushrod angle to such a degree that getting proper pushrod geometry is very difficult and increases the likelihood that all the cam data is not being transmitted to the valve not to mention the potential for increased valvetrain wear. These problems can be mitigated somewhat by using a bolt down roller rocker (expensive) which eliminates the need for a pushrod guide plate. Another strategy is to use a hydraulic roller cam with a solid roller lifter which is shorter and reduces the pushrod angularity but the solid roller lifter will usually have a much shorter life in street use.

My point is that none of that is necessary to make 650 hp with a 557 cubic inch BBF. It can easily be done with a flat tappet cam for a lot less money.
 

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Thanks Tommy, for taking the time to explain it. Makes perfect sense and I'm thinking that a reduced diameter cam grind base circle would help a little too, like they do for small block Chevies in order for the rod shank to miss the cam lobes.
 
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