New block source

[Gaugster]

Well, I'm basically the "dumb blond" around here but there is a valve aspect to all of this for some. I believe Aluminum blocks use to cost substantial more than it's iron counterparts. That cost delta seems to have moderated over the years for the popular engine platforms. But if a substantial premium did exist AND the aluminum engine underperformed on the Dyno/street...it could explain why the topic gets debated so thoroughly from time to time.

[blykins]

Well, I'm basically the "dumb blond" around here but there is a valve aspect to all of this for some. I believe Aluminum blocks use to cost substantial more than it's iron counterparts. That cost delta seems to have moderated over the years for the popular engine platforms. But if a substantial premium did exist AND the aluminum engine underperformed on the Dyno/street...it could explain why the topic gets debated so thoroughly from time to time.

Depending on the manufacturer there could be as much as $2500-3000 difference between a cast iron block and an aluminum block.  That would about be the scenario between a BBM cast iron and a Shelby aluminum. 

[Posi67]

I bought an Aluminum BBM some time ago for my "dream" build. Will it make less power than an Iron block?? Don't care if it does because I want the weight savings off the nose of my car. Will it make all the power I need or can use? Don't see why not because I'll put all the Cam, Compression and RPM into it that makes the HP question moot.

Other situations would obviously dictate a different route so build for what you are doing. My friend's SBF Comp Eliminator engine is an iron block/steel rod deal because that makes the most power. He did build a billet Aluminum SBF for a guy a few years back that was for a nitrous combo and it made 998 HP without the nitrous. More cubes than his iron block, smaller cam but similar HP. Bottom line is do you need max HP or just have a sane goal in mind.   

[cjshaker]

I bought an Aluminum BBM some time ago for my "dream" build. Will it make less power than an Iron block?? Don't care if it does because I want the weight savings off the nose of my car. Will it make all the power I need or can use? Don't see why not because I'll put all the Cam, Compression and RPM into it that makes the HP question moot. 

Not directed at you, Dale, but nobody was saying that aluminum is bad, just has a trade-off, like all things. Just from what I've gathered from reading (so take it for what it's worth), the weight savings pretty much levels out the power loss, or even gains you some. "They" say that losing 100lbs typically equals a drop in ET of a tenth? I don't know how accurate that is, but I'd assume that pretty much offsets any loss in power that may come with aluminum. My SOG block was 50lbs heavier than a factory 427 block, so that's a lot of extra weight on the front. I'm not sure how much a BBM aluminum weighs, but I'd guess it's at least a hundred pounds less than the BBM iron.

I certainly could use the weight savings on my car. I just couldn't afford an aluminum block.

[Autoholic]

BBM lists their iron FE blocks as weighing ~250 lbs and their aluminum FE blocks as weighing ~125 lbs. So half the weight.

[cammerfe]

BBM lists their iron FE blocks as weighing ~250 lbs and their aluminum FE blocks as weighing ~125 lbs. So half the weight.

And you'll notice that the Kirkham block, bare---no sleeves---is quoted as weighing 65 pounds, is it not?

KS

[frnkeore]

The video, says 64lb but, that's w/o sleeves, main caps and bolts, for the caps.

I would add ~25lb for sleeves and another ~10lb for the caps and bolts or, ~100lb.

A good weight saving for a all out race engine but, also very expensive per lb.

I would say that for those that don't have to ask prices, it is a very good upgrade. Other good upgrades would be titanium headers and magnesium intakes. Titanium rods are 1/2 the weight and reduce rotating loads, too.

As weight reduction goes, cast magnesium is the same strength as cast aluminum but, is 1/3 lighter. So, mag timing covers, valve covers, oil pans, water pumps (mag doesn't do well with water tho) and bell housings. As well as light weight, neutral balanced crank shafts.

While magnesium isn't used much today, in the '70's, it was used a lot in top classes.

The old saying,

"take care of the ounces and the pounds, will take care of themselves"

  has always applied to racing and will never change.

[Dumpling]

Why magnesium? Has all kinds of issues. Nowadays, go for carbon fiber.  I've seen a carbon fiber intake and valve covers for the FE. Timing cover, oil pan shouldn't be too hard. I imagine a carbon fiber water pump would just be a matter of money

[cammerfe]

Just out of curiosity, do you have a source for the carbon fiber valve covers?

KS

[frnkeore]

I have absolutely nothing against carbon fiber! I was just trying to show, that you can loose 1/3 of the weight of typical cast aluminum parts by going to magnesium and not have to deal with any new tech.

But, my main point was that you can loose a lot of weight w/o going to a aluminum block or in addition to the aluminum block.

The thing is, all other things equal, who will get to the 1320ft mark, or finish line first. The engine adorned in Aluminum, Carbon fiber, Magnesium and titanium or the engine that has a lot of cast iron, left on it?

How many people have said that they would NEVER buy something because it's to expensive, only to whine up with it on their car at some future date?

I am not in the income bracket that doesn't have to ask what something costs, I actually way below it but, there are people on this forum at are in that bracket or very near it and for the subject at hand, they can lead the way.

[Posi67]

If I was wanting or needing a 900 plus HP engine I would have bought an Iron block because even though I'm stubborn I sometimes listen to people smarter than me. I could also go big Cube, aluminum rad, electric water pump, gut the interior blah blah to go faster but I have a tire limited car that most think is pretty cool as is. I have a HP goal in mind that is reasonably sane and will turn up the RPM as needed. Up to this point everything I've run has been a compromise of good and bad parts so it's time to do this right. My distributor hold down will be a Ford piece however.   

[machoneman]

Like pretty much everything automotive, there are trade-offs to consider for sure. A harsh ride used to equal a fast cornering car yet with modern electric shocks, one can easily switch from a near-luxury ride to a corner carver in newer cars. Point is, when it comes to aluminum engine components versus cast iron, at least these days one has many options to choose from. Yet, these FE engine parts don't lend themselves to hitting a switch on your dashboard to make it go faster or ride more smoothly or get better mileage.

I also like the idea of an aluminum blocked anything these days as the auto makers have perfected making all kinds of engines in all-aluminum trim. Yet, an FE, 385 series or SBF is different as they were not designed, so to speak, in aluminum trim. Today's modern engines were extensively tested by the engineers on dynos, in-car operation and more. Not quite the case with an aluminum blocked FE, eh?

We therefore must rely upon our noted aftermarket FE builders (and those of other makes) to learn of the benefits and pitfalls of running aftermarket aluminum blocks. The shortcomings have been pretty well explained here and in many past posts on this site and other Ford-oriented sites. I'll finish by saying that one's intended use (full race, street, occasional drags) and one's desire to avoid or welcome routine maintenance has as big a bearing on the iron versus aluminum question as does the big price difference.

   

[cjshaker]

I'll finish by saying that one's intended use (full race, street, occasional drags) and one's desire to avoid or welcome routine maintenance has as big a bearing on the iron versus aluminum question as does the big price difference.

 

Just a reminder that the Millers use an aluminum block in their Drag Week Cougar. A thousand street miles in one week, raced every day....and beats some pretty hefty competition. All with pretty much zero issues, except for a couple of wore out rockers one year. It's a Shelby block, so not your 'average' aluminum block, but still aluminum. I believe they go a couple years between refreshs. It'd be hard to make up that extra .1-.15 they would likely lose in ET when adding another 100-150 lbs to the car.

Anyone know how much horsepower would be needed to gain a tenth, under same conditions?

[cammerfe]

It's often said that a hundred pounds is worth a tenth. If all that weight comes off the front half of the car, it might even be worth more than that. So long as I can be assured of enough strength, I'll deal with all perceived negatives of going with aluminum. I'll be able to tell you more in coming months.

KS

[blykins]

A tenth is about 25-30 hp.