Aluminum vs iron

[cazsper]

Seeing that I "grew up" with the Windsor motors, it was very obvious what the steps were going to be if I wanted to make any decent power. Stroker or not, aftermarket aluminum heads and intake, a custom cam and whatever induction you were going with.

Of course the same can be done for the Cleveland but how much is worth it? If you wanted all out power, you just go with a big block. But when it comes to the Cleveland, are the heads just "suitable" or are they just as good as any aftermarket head but just made out of iron?

Let's say I were to build a 10:1 393C with a healthy streetable cam. All backed by a TKO-600 and 3.50:1 gears. I really like the idea of the Edelbrock Air Gap intake. But what about the heads (4v)? Would I get more from a set of aluminum 4v heads? Or even the 3v heads from CHI?

I'm just curious.

 

[Tnfastbk]

This is one of those debate that can go on forever. The 4v heads flow more than most aftermarket heads, but flow is not the whole picture. The aluminum will dissipate heat better and are definitely lighter, etc. So the bottom line usually is what do you want. I always wanted to build an aluminum headed 351C so that's what I did. But the ones I went with are raised port AFD SP4V ones that don't allow me to run ram air and are pricey. I have even thought of removing mine and building my iron heads to run ram air, but not to that point yet, So do your homework.

http://www.airflowdynamics.com.au/site_flash/products/cleveland_heads.htm

 

[c9zx]

The stock iron 4-V head will support a lot of power, open or closed chamber. The increased displacement just helps make the power at a lower RPM. Several of the Australian heads will make more power but are expensive and only Scott Cook makes a dual plane intake that is compatible with the heads (that I am aware of). I've not yet seen the ED performer RPM Air Gap compared to anything else on a dyno so I won't speak to that other than to say the runners are 2V sized which could be a good or bad thing depending on the build specifics. Many have raised exhaust ports as well than can make header fitment a problem. And they are pricey in my opinion, +$3k for complete heads and intake to match. That is not to say you won't spend more than you think you should to properly prepare a set of iron 4V heads ($1000-$1200) but, you'll have "off the shelf" choices for intakes and headers. It is critical that the machine shop has the proper equipment, knows how to use it, and is meticulous. Getting valve train geometry right is also critical for power production and longevity. I guess that is a long way of saying I'd use a properly prepared set of iron 4V heads and keep the compression between 9.3-9.8. Pump gas is not what it used to be and getting worse. Chuck

 

[hyena429]

Stock 4v cast iron heads will flow much more horse power than your block can handle.... Reason why not many aftermarket performance heads made for the cleveland...The stock 4v ones are already full race..lol...but like tnfastbk says...some benifits...lighter...run a bit cooler....but they do cost a arm and a leg...And yes this debate can go on and on but if you just worried about horse power...the stock 4v heads with the right mods will pull insane horse power.

 

[Wolverine]

Let's face it, one of the reasons there are soooo many performance aluminum heads on the market is they are easily machined.

If money is NO OBJECT, I would venture to say you will be able to purchase an aluminum head/intake setup that will far outperform stock iron heads regardless of your application.

However, what does outperform mean to you?

If you are looking for streetable 400HP, you can get there easily and more with stock iron.

If you are looking for 500HP+ and ET times are a concern, you probably want aluminum.

You can always start with iron, then reach into your wallet if you want more.

 

[cazsper]

Really great advice everyone. I appreciate it.


When it comes ti building my next motor, I should do what Glock did. Got a panel of the best and had them design it.


When it comes ti building my next motor, I should do what Glock did. Got a panel of the best and had them design it.

 

[marks73]

I guess it depends on if there is a helicopter flying overhead with a $50,000 check for the winner. Depends on what your driving for. Me, I can beat about anything on the street with cast iron just the way they were designed. And still do what I want on a dailey basis with it.

 

[Tnfastbk]

I guess it depends on if there is a helicopter flying overhead with a $50,000 check for the winner. Depends on what your driving for. Me, I can beat about anything on the street with cast iron just the way they were designed. And still do what I want on a dailey basis with it.

HMMMM ya think?

 

[cazsper]

That sounds promising.

 

[marks73]

Can't wait Roy! (course now I'm going to get your Uncle Joe to set my carb for me!)

 

[c9zx]

The horsepower limit on the iron 4V heads is quite high. My pump gas 9.6:1 408C makes 529 @6400 (standard correction on the dyno). An 11.75:1 404 inch clevor I built 17 years ago made somewhere in the neighborhood of 570 HP (based on known weight and MPH in 1/4 mile calculation). So unless you need a lot more than that, the iron 4V heads should suffice (if properly prepared) unless, you just want and appreciate the aluminum heads enough to pay the entry fee. As Roy has said it depends on what you really want and are willing to pay for. I have no idea why I'm unable to resist commenting whenever this subject come up. Nuff said. Chuck

 

[cazsper]

No, please comment. I like the idea of a stroker 393/408. But I also like the idea of a big block. It's like getting torn in two different directions. I guess I just need more cars..lol.

Would you happen to know the cam specs of your 408? I hate asking that question because it seems like I'm asking a personal question. I'm just trying to get all the facts together before I decide in my next move.

I have a bare block sitting in storage just waiting for a 520 stroker kit and some crazy heads of some sort. But I also have the 4v Cleveland in my car now that seems to run just fine. But it has a single plane intake and could probably benefit from a nice dual plane.

 

[helldive]

A man who used to run 351c in his roundy round car is building my 393 stroked Cleveland right now.

I'm using the 4v heads with valve job and SS vales with hdy flat tappet cam. He advised the Eagle

bottom end kits are what he prefers to use because their rods are truer then Scats.

Also going with the edelbrock torque intake manifold... should have pix soon.

Hes promised me to see about 550hp out of this combo.

 

[cazsper]

That's not the first time I have heard that about Scat. You think they would fix that.