460 Build

[VegasFastback]

I've stumbled into some 460 blocks and am deciding how I want to build them, at least one. There are some C8 heads for sale near me and he said he also has a pair of C9 heads. The C8's have been rebuilt. One question I have is how much meat do these heads have for porting? I read in an article that the exhaust ports are thin on the bottom and trying to port them causes you to break into the water jacket. Im not planning on stroking the build. Is there any pitfalls I should be wary of? This is just going to be a have fun engine, so I'm more focused on experimenting with parts than hitting a magic HP number.

 

[TommyK]

BBF iron heads do not require a lot of work to be able to support 500 hp. Below is a link which describes how to acheive this.

http://www.460ford.com/forum/showthread.php?t=143753&highlight=187+cfm

The original poster of the thread has a website you can join for a fee with complete porting instrictions.

 

[cobra3073]

...what Tommy said!

As I often say, the 71 - 73 Mustangs were built to work with the 429/460 engines, in my opinion.

We have several folks here on the Site who have taken this route and I am sure you will receive all kinds of GREAT advice "on your journey."

BT

 

[cazsper]

I have also considered a 460 based build. If you google 460 horsepower chart, there are a bunch of "recipes" for specific hp numbers. It's pretty specific:

425-450HP 460ci

Intake System: 750cfm Holley DP professionally calibrated for your application Edelbrock Performer Rpm Intake Manifold Cylinder Heads: D0VE head with mild port job, chambers polished, and port match (315-ish/180-ish cfm @.600) Intake valve size 2.08 Exhaust valve size 1.65 Roller rockers.

Short Block: Comp Cam Custom Spec Hydraulic flat tappet cam or equivalent Based on the Xtreme Energy Hydraulic Series Intake Lobe 5443 and Exhaust Lobe 5203 (Specs:268/280 adv., 224/[email protected], .524/.544 lift, 110 LSA) Compression around 9.5:1 Stock crank Stock rods with good bolts Standard volume oil pump Stock oil pan with windage tray

Exhaust: 1 7/8" headers to dual 2.5" pipes with H-pipe. Good flowing 2.5" Magnaflow mufflers or equivalent.

Summary: 91-octane. Keep redline to 6000 rpm.

I know you're not looking for specific numbers however, by checking out those "recipes" it may help to understand what works together..

 

[barnett468]

.

get it balanced.

install a 72 holley main jet in the top of the head where the oil feed is for the rocker arms.

install the later model "cobra jet" oil filter adapter.

 

[73Vert302]

I have some 460 heads you can have for the cost of shipping. They are d3ve. I have some other extra parts also-all stock from a 1985 (i think) non efi 460. Mine is at my builder-he is taking his time but the motor will be bada$$ when its done.

 

[VegasFastback]

BBF iron heads do not require a lot of work to be able to support 500 hp. Below is a link which describes how to acheive this.

http://www.460ford.com/forum/showthread.php?t=143753&highlight=187+cfm

The original poster of the thread has a website you can join for a fee with complete porting instrictions.

Thanks this is exactly the kind of stuff I'm looking for.

I have also considered a 460 based build. If you google 460 horsepower chart, there are a bunch of "recipes" for specific hp numbers. It's pretty specific:

425-450HP 460ci

Intake System: 750cfm Holley DP professionally calibrated for your application Edelbrock Performer Rpm Intake Manifold Cylinder Heads: D0VE head with mild port job, chambers polished, and port match (315-ish/180-ish cfm @.600) Intake valve size 2.08 Exhaust valve size 1.65 Roller rockers.

Short Block: Comp Cam Custom Spec Hydraulic flat tappet cam or equivalent Based on the Xtreme Energy Hydraulic Series Intake Lobe 5443 and Exhaust Lobe 5203 (Specs:268/280 adv., 224/[email protected], .524/.544 lift, 110 LSA) Compression around 9.5:1 Stock crank Stock rods with good bolts Standard volume oil pump Stock oil pan with windage tray

Exhaust: 1 7/8" headers to dual 2.5" pipes with H-pipe. Good flowing 2.5" Magnaflow mufflers or equivalent.

Summary: 91-octane. Keep redline to 6000 rpm.

I know you're not looking for specific numbers however, by checking out those "recipes" it may help to understand what works together..

The problem with looking at recipes is that its not conducive to what I'm trying to accomplish. This will be my third engine build but first modded motor. Basically I'm testing my own understanding of how to sync all the components of an engine, so I can't refer to builds as a whole but rather how each piece was treated individually to achieve the goal. This is why my first question is about heads. Next will be some specifics about cams. I don't know if this explains my goal. I'm really bad at communicating in type.

.

get it balanced.

install a 72 holley main jet in the top of the head where the oil feed is for the rocker arms.

install the later model "cobra jet" oil filter adapter.

Will I need to tap it first? I assume this is to send more oil to the mains. Is there any way I can get a picture of this? Also Why the cobra jet filter?

I have some 460 heads you can have for the cost of shipping. They are d3ve. I have some other extra parts also-all stock from a 1985 (i think) non efi 460. Mine is at my builder-he is taking his time but the motor will be bada$$ when its done.

How much is shipping from OH to OR?

 

[73Vert302]

I will check today.

 

[TommyK]

I am not an engine building expert but here is what I know based on my own "build".

The choice of whether to use the small chamber early heads (C8, C9, D0) or the large chamber later heads (D3) is largely a matter of desired compression ratio and piston selection. They both have the same flow potential.

If you are using a stock shortblock as the starting point for your build as I did, you will need to know if it has flat top or dished pistons in order to determine which head will produce a compression ratio suitable for pump gas (assuming that is your goal).

In general pre 1973 shortblocks will need large chamber heads, post 1972 will need small chamber heads. Depending on details these combinations will produce compression ratios around 9 to 9.5:1. A shortblock which uses factory post 72 dished (bathtub) pistons and D3 heads will only have around 8:1 compression which IMO is not suitable for any type of N/A performance build.

If you are assembling your shortblock from scratch then either head will work based on what pistons you select for the build.

 

[cazsper]

Not to criticize anyone's build (because I don't know) but when building a motor, do you build it around the heads or do you pick the appropriate heads for the short block? This is when building an engine from the ground up of course. I totally understand picking chamber sizes for an existing short block.

 

[barnett468]

Not to criticize anyone's build (because I don't know) but when building a motor, do you build it around the heads or do you pick the appropriate heads for the short block? This is when building an engine from the ground up of course. I totally understand picking chamber sizes for an existing short block.

if you already have a fixed engine displacement, you decide how much power you want and buy the proper parts to get you there . . all parts must be matched if it is to get optimum perf.

 

[TommyK]

Not to criticize anyone's build (because I don't know) but when building a motor, do you build it around the heads or do you pick the appropriate heads for the short block? This is when building an engine from the ground up of course. I totally understand picking chamber sizes for an existing short block.

IMO if it is a clean sheet build you first identify your goals, then pick the "best" head to achieve those goals and tailor the rest of the components around those parameters.

 

[VegasFastback]

I am not an engine building expert but here is what I know based on my own "build".

The choice of whether to use the small chamber early heads (C8, C9, D0) or the large chamber later heads (D3) is largely a matter of desired compression ratio and piston selection. They both have the same flow potential.

If you are using a stock shortblock as the starting point for your build as I did, you will need to know if it has flat top or dished pistons in order to determine which head will produce a compression ratio suitable for pump gas (assuming that is your goal).

In general pre 1973 shortblocks will need large chamber heads, post 1972 will need small chamber heads. Depending on details these combinations will produce compression ratios around 9 to 9.5:1. A shortblock which uses factory post 72 dished (bathtub) pistons and D3 heads will only have around 8:1 compression which IMO is not suitable for any type of N/A performance build.

If you are assembling your shortblock from scratch then either head will work based on what pistons you select for the build.

Both blocks have flat top pistons, but the blocks also need to be bored so they're irrelevant. So, the heads will determine whether the pistons are dished or not.

Not to criticize anyone's build (because I don't know) but when building a motor, do you build it around the heads or do you pick the appropriate heads for the short block? This is when building an engine from the ground up of course. I totally understand picking chamber sizes for an existing short block.

If given a choice the heads would be based off what RPM I want to run the engine at but I'm broke and this limits my options so this build will revolve around the heads.

 

[MotoArts]

Plenty of fun can be had below 5000 RPM with a 460.

You won't need to spin it like a chainsaw to get a grin

My 460 was built with this premise in mind. Stock dished piston bottom end, C8 heads, Lunati Bracketmaster cam (1500-5K range), Edelbrock Performer w/ a 3310 Holley 750.

There's more money in the intake and carb than the rest of the engine.

And it should last forever if treated right...

 

[VegasFastback]

What CFM do you want the exhaust to flow compared to the intake ports. I ask because you generally want intake valves larger than exhaust valves. I think there is a 20% between the valves, I'll have to look it up, but the ports might need a different ratio when it comes to flow.

 

[MotoArts]

Here's something to think about, since it seems we're in the same cash crunch...

Exhaust.

When I install my 460 (someday), it will be with stock manifolds to start.

Now the concern over flow is negated in my case.

Headers for this engine aren't inexpensive by any stretch, and I haven't heard many folks that haven't had to whack on 'em to get to fit regardless of manufacturer.

There's just no way I'm gonna whack on a set of $600-1000 tubes. Nuh uh.

I don't hear nearly as many complaints from Windsor and Cleveland owners...

Besides, I've witnessed a grandma stock, fat block '69 Thunderbird do 13.90's on street tires before.

That's good enough for me.

 

[TommyK]

What CFM do you want the exhaust to flow compared to the intake ports. I ask because you generally want intake valves larger than exhaust valves. I think there is a 20% between the valves, I'll have to look it up, but the ports might need a different ratio when it comes to flow.

I don't know that I have seen a recommendation for I/E flow ratio specific to 385 series heads at the power level I think is being contemplated here. The books say 70% but the books are usually written about Chevies. A wise man once said "engines can't read".

The OEM heads have a great flowing intake port and a poor flowing exhaust. The factory valve sizes will support 500-550 hp if the heads are properly ported. The advice I see given by the engine builders on the 460ford forum is that porting the exhaust is paramount and flows of 180-190 cfm are attainable by the home porter.

The stock intake port already flows pretty well (350ish?) but it is still recommended to at a minimum perform a bowl blend and address the short turn to reach the 500-550 hp potential of the heads.

The next recommendation for power gains is usually to install a 2.11 intake valve. After that 2.25 intake and 1.75 exhaust are the max sizes that can be accommodated without getting into major re-work.

It is important to remember that flow is just a part of the equation. Velocity and turbulence play at least an equal role. There are very specific recommendations for where and how much material should be removed to get the best performance from a BBF iron head.

HTH

 

[73mach1]

If you are going to port your own heads I highly suggest you go to http://www.reincarnation-automotive.com/ . Go bbf technical index and join , I think it's 25 or 30 bucks, I can't remember what I paid. It a wealth of information and pictures on how to port bbf heads from someone that really knows bbf's .

 

[VegasFastback]

What CFM do you want the exhaust to flow compared to the intake ports. I ask because you generally want intake valves larger than exhaust valves. I think there is a 20% between the valves, I'll have to look it up, but the ports might need a different ratio when it comes to flow.

I don't know that I have seen a recommendation for I/E flow ratio specific to 385 series heads at the power level I think is being contemplated here. The books say 70% but the books are usually written about Chevies. A wise man once said "engines can't read".

The OEM heads have a great flowing intake port and a poor flowing exhaust. The factory valve sizes will support 500-550 hp if the heads are properly ported. The advice I see given by the engine builders on the 460ford forum is that porting the exhaust is paramount and flows of 180-190 cfm are attainable by the home porter.

The stock intake port already flows pretty well (350ish?) but it is still recommended to at a minimum perform a bowl blend and address the short turn to reach the 500-550 hp potential of the heads.

The next recommendation for power gains is usually to install a 2.11 intake valve. After that 2.25 intake and 1.75 exhaust are the max sizes that can be accommodated without getting into major re-work.

It is important to remember that flow is just a part of the equation. Velocity and turbulence play at least an equal role. There are very specific recommendations for where and how much material should be removed to get the best performance from a BBF iron head.

HTH

Yeah, I looked it up and I wrote the ratio wrong. The rule of thumb is a ratio of 75% if the ports flow at the same rate. Low compression calls for an increase in exhaust valve size, high compression and you can shrink it. The books I have didn't say it but in the case of the 460 heads I might want a larger exhaust valve to combat the poor flow of the port. I'll see when I actually get to porting. The D2 heads I have will make excellent test subjects before I do one that will actually go on the engine.