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Aluminum heads 289

15014 Views 37 Replies 17 Participants Last post by  kenash
I am buying a recently rebuilt 289 bored .30 over, mild comp cam, comp stock style roller rockers and I'm assuming stock style pistons. I want to swap the existing heads on them with aluminum. I know nothing about the specs on cylinder heads and what can be run with what. Not trying to get crazy but I want to upgrade. Any help would be appreciated.
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I have read about AFR heads on here. This is going to be a cruising track time. I will have to remove the heads that are on there and look at the pistons. Just assuming they are completely stock (if there is such a thing as a "stock style" piston) would those AFR 165 heads work well?
Thanks for the compliment kenash!

I really like the look of aluminum heads. It is more for show because it will never see a track or drag strip anytime. A nice bump in HP for cruising would be nice though. I know the engine was rebuilt with all stock components. I looked at summit racing and all I could find was Sealed Power brand kits. Their pistons look like the ones attached. I have attached a pic of the engine too.

If it matters, I am planning on running on an Edelbrock Performer RPM intake with shorty headers. If need be I can change the Comp roller rockers that are on there now.

Long story short.....I want simple aluminum heads that look good and require no extra machine work with my stock internals and Ebrock intake, etc.


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I did look at those but wasn't for sure about them. Any other thoughts? Those AFR 165 heads claim they fit with no mods but they are pricey.
I have been researching the AFR 1472 165cc heads and the AFR 1402 165 cc heads. Both say they will fit all stock components with no other modifications. Looks like the combustion chamber size is a bit bigger on the 1472...60 cc compared to 58 cc. The only other difference I saw was the exhaust port location was raised on the 1472 and standard on the 1402.

Airflow Research (AFR) 1402 - AFR 165cc SBF Outlaw Street Heads - Overview -

Airflow Research (AFR) 1472 - AFR 165cc SBF Outlaw Street Heads - Overview -

As mentioned above, my planned setup with Ebrock Performer RPM intake and shorty headers.....does everyone think these heads will be good with no mods?
Did you think about having your current heads ported?

That is what I did to mine and am very happy with it.
What would be the difference in power with porting the stock heads compared to adding aluminum heads?? Noticeable difference?

Would a machine shop need to see the pistons if they are just porting the stock heads? What kind of work can be done to stock heads to increase power? I apologize if I sound ignorant, but I am just not familiar with this part of the engine.
Porting stock heads to a level where it makes a noticable difference is not very difficult (like 22GT more or less said). They can also be ported to be on par with entry level aluminum heads, but then you need to know what you're doing (although it's still no rocket science, just a lot of work).

For your mild power goals, porting the stock heads would probably be sufficient. Of course, they won't look like aluminum heads.

The pistons you have, have very large valve reliefs (like 8 cc), which lowers the compression quite a bit, so aluminum heads would probably need to have their combustion chambers reduced to around 55 cc in order to keep compression ratio reasonable.

A .030" over 289 has a displacement of 4805 cc or 600 cc/cylinder. Required volume at TDC for a certain compression ratio is displacement/(CR-1).

To achieve a 9:0 compression ratio: 600/(9-1)=600/8= 75 cc
The valve reliefs are 8 cc, the gasket around 9 cc, so the combustion chambers in the heads need to be around 75-8-9= 58 cc. Maybe a few cc's less, depending on how far your pistons are down in the bore. With everything per stock nominal dimensions, that would account for ~2cc.

To achieve a 10:0 compression ratio: 600/(10-1)=600/9= 67 cc
The valve reliefs are 8 cc, the gasket around 9 cc, so the combustion chambers in the heads need to be around 67-8-9= 50 cc. Again, maybe a few cc's less, depending on how far your pistons are down in the bore. Such small combustion chambers would of course require milling, possibly pushing the save milling limits of the heads.

Of course, you could go for 9.5 which would require less milling.

This is probably a simple formula but sure sounds complicated! I bet if I took the engine to a machine shop they could tell me what would match up properly. It just sounds like no matter what route I take it will require some machining to get everything right.
I had these heads recommended to me by a friend of mine. They claim they are one of the few performance aluminum heads that are direct replacement for stock Ford heads and stock pistons. I have heard great things about Trick Flow heads. Summit is offering $100 Summit Bucks too.

Trick Flow Specialties TFS-51400004 - Trick Flow® Twisted Wedge® 170 Cylinder Heads for Small Block Ford - Overview -
Calculating CR is not that complicated, once you understand the principals involved. Think of it this way. You have a stock engine, all parts being considered, the factory lists the CR (compression ratio as "X" value. To calculate CR, the formula model needs:
bore dia.
head gasket bore dia.
compressed gasket (after torquing heads)
Chamber CCs (mfg will offer)
valve reliefs CCs (if piston has valve reliefs cut-in) (this number is a negative number for calculation)
Dish CCs (if piston has a concave relief)(this number is a negative number for calculation)
Domed CCs (if piston has a raised surface, or opposite of dish)(this number is a positive number for calculation)
Area between the piston and wall and between the top ring (compression) and surface. (In a number of cases, this is known to be about 2 CCs./ hole.
The known depth (in the hole) when the piston is at true TDC. The number can be listed as either a "-" minus number, a positive "+" (piston protrudes out of the hole slightly), or "Zero", piston is "dead" even with the block surface. As an example, my piston is "out of the hole -.005", for calculation purposes.)

Once these "knowns" are entered into a CR calculator, and the CR is revealed. Any deviation to the entries will change the CR. For example, if you decide after the fact to "clean up" the combustion chamber, by bowl blending etc. (this removes metal). This, in affect, increases the CCs of the combustion chamber. This increase will reduce the CR. because you "opened up" or increased the total volume of the equation. So, simply stated, if you remove metal or increase the bore, increase the "compressed" gasket to, let's say .041, from .039, this will reduce CR.
These basic calculations provide you, what is typically known as "static" CR. This is what we all typically discuss and hype.
However, I won't go into it as it may add a layer of confusion, but the actual CR that occurs with an engine in operation can, actually, be lower by as much as a point! This CR is referred to as "dynamic".
I hope you gain something from this. For others, if I've miss-stepped somewhere, let me know. I'm old, it's getting late, and I want a beer!
Happy Trails!
That was quite the description....I really appreciate you taking the time to explain that. I get the general idea, but I am just not savvy on the internal components of the engine as much as external parts...just lack of experience I guess....never torn into the inside of an engine.

Essentially what you are getting at is that there is no such thing as a "Bolt on and go" type head? As mentioned, all I know about the engine is that everything is stock but the cam and it is a mild upgrade.

I just want the easy way out lol!!! Just trying to find something that says it can be used with stock components. Those trick flow heads appear to be what I am looking for. Could those heads be potentially detrimental to my CR? Would that particular head I linked to potentially increase or decrease my CR? I have no plans to ever change anything on the new heads or change from my stock .030" pistons.

Again, I really do appreciate you taking the time to explain.
Those heads with the right hardware and the following pistons "can" make excellent power. with the right cam and supporting systems. That is, if you do not exceed a specified gross lift. Someone here mentioned a total "lift" that, if "not exceeded", would work with your stock style pistons. Re-read for this.
I can tell you, I'm running these heads, my gross lift is .570/.562, and I needed them.
Hope this helps.

I will check and see if I can find the lift specs on the cam. I know the guy I bought the engine from said it was a "mild RV Comp cam". I know my lift would never exceed your specs.

Is it also possible to increase CR by adding a thinner gasket?

I need to give 6t9mach1 the credit for bringing those trick flow heads to my attention first!

If I pull the heads tomorrow and take pics can you all help me determine my CR using kenash's formula?
Can you tell more about these?

After reading this entire post Ive come away with this:
1. You want the aluminum heads mostly for bling effect
2. You dont have a budget for these

I think the TW heads you are looking at are overkill considering the rest of the engine but they are actually not that expensive relative to some other AL heads (Slummit owns Trick Flow and discounts their heads big time). Porting iron heads can give good performance and can cost less than AL heads but never forget the performance gained by the reduced weight of AL heads - its not insignificant. Usually the disadvantage to going with any AL head is the cost of upgrading the valvetrain (rockers) but singe you have these already it may be a wash. Thats why I asked about them.
These are the rockers I have now.

I spoke with a very reputable racing engine shop today, Henson's Racing Engines, and the owner said given the current setup he would recommend upgrading the cam to a hydraulic roller cam and using these heads:

Edelbrock 60229 - Edelbrock Performer RPM Cylinder Heads - Overview -

If I did not want to upgrade the cam then the E-Street series would work just fine:

Edelbrock 5023 - Edelbrock E-Street Cylinder Heads - Overview -

Both probably matched with this intake:

Edelbrock 7121 - Edelbrock Performer RPM Intake Manifolds - Overview -

Who knows what I will decide. The roller cam could produce a bit more HP than I need or can pay for with stock drivetrain. Budget is a concern, but I did not pay anything for the motor and am selling the extra parts that came with it. I am considering these roller rockers:


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Along with frustrating myself, I am probably making all of the readers mad lol!! I will get this figured and and post the outcome. Thank you all for the direction and advice!
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