What's the appeal of an aluminum engine block?

[jkg2101]

In response to the original question on this thread, I am currently building my kirkham (finally received it!).

I purchased an assembled 'short block' from Blair Patrick (who I might add is very knowledgeable and did a great job, and is a true gentleman). He and I agreed right from the beginning to go with an iron block. I was able to get one of the BBM's in iron.

I am not thrilled about the offshore casting, but doing my part to support USA businesses.

I did not and don't personally see any reasonable reason to want aluminum. i recognize it may be more prone to some build trouble, and it is more expensive. I honestly don't think it affects resale price (but if I was in this for resale, then I have other problems anyway...)

I agree that many here have admitted it is more emotion and less logic that lead them to aluminum. My car will be every bit as nice with a well done sideoiler build in iron.


I do run aluminum heads and intake, for a variety of reasons (weight savings and nothing comparable in iron available).

justin

[RodKnock]

Originally Posted by jkg2101

In response to the original question on this thread, I am currently building my kirkham (finally received it!).

I purchased an assembled 'short block' from Blair Patrick (who I might add is very knowledgeable and did a great job, and is a true gentleman). He and I agreed right from the beginning to go with an iron block. I was able to get one of the BBM's in iron.

I am not thrilled about the offshore casting, but doing my part to support USA businesses.

I did not and don't personally see any reasonable reason to want aluminum. i recognize it may be more prone to some build trouble, and it is more expensive. I honestly don't think it affects resale price (but if I was in this for resale, then I have other problems anyway...)

I agree that many here have admitted it is more emotion and less logic that lead them to aluminum. My car will be every bit as nice with a well done sideoiler build in iron.


I do run aluminum heads and intake, for a variety of reasons (weight savings and nothing comparable in iron available).

justin

Just facts first. I think I counted 8 owners of alloy blocks on this thread who said that the reason for buying an alloy block was weight. Your BBM weighs 250 lbs and my Shelby alloy block is 125 lbs. Pond's alloy block is 135 lbs. So the weight savings is NOT EMOTIONAL to those 8 alloy block buyers. You couldn't find any "reasonable reason" for alloy, but at least 8 actual buyers on this thread found "weight savings" as reasonable.

Personally, I think most of us here bought a Kirkham for the liberal use of lightweight aluminum throughout the car. And some of us said that installing an iron block in a virtually all aluminum Cobra makes/made no sense.

Finally, weight savings wasn't the only reason I bought my Shelby aluminum block. The Shelby block was made in America and, at the time of purchase, was about $1,000-$1,500 more than an iron block. So, the Shelby block price wasn't a major factor for me, relative to the entire Kirkham build. Also, the Shelby block could be made into a 526 or 527 one day, if i so desired. The other blocks at the time couldn't go that big. One last reason, semi-related, is that the Shelby block was considered "beefier" and had the Shelby-specific head studs, which allowed (for lack of a better verb/term) the Shelby alloy block to withstand a higher RPM before going "kablooey."

So my alloy purchase had zero to do with emotion and had everything in the world to do with weight savings, price, beefier build, and potentially bigger cubic inches than competitors.

As for resale, 66GTK, who seems to buy and sell quite a few Cobras, mostly ERA's I'd speculate, stated that a Cobra with an alloy block is more desirable or sell for a higher price than one with an iron block. And all other things being equal when evaluating a Cobra for purchase, I'd chose the Cobra with the alloy block too.

[fordracing65]

Originally Posted by jkg2101

In response to the original question on this thread, I am currently building my kirkham (finally received it!).

I purchased an assembled 'short block' from Blair Patrick (who I might add is very knowledgeable and did a great job, and is a true gentleman). He and I agreed right from the beginning to go with an iron block. I was able to get one of the BBM's in iron.

I am not thrilled about the offshore casting, but doing my part to support USA businesses.

I did not and don't personally see any reasonable reason to want aluminum. i recognize it may be more prone to some build trouble, and it is more expensive. I honestly don't think it affects resale price (but if I was in this for resale, then I have other problems anyway...)

I agree that many here have admitted it is more emotion and less logic that lead them to aluminum. My car will be every bit as nice with a well done sideoiler build in iron.


I do run aluminum heads and intake, for a variety of reasons (weight savings and nothing comparable in iron available).

justin

What kind of power did the engine make. What were the specs. Did you also use BBM heads.

[jkg2101]

I didn't dyno the assembled engine. it has a 3.98 stroke (428 stroke) - i would have done a 3.78 stroke (stock 427) but there arent any reasonably priced cranks available in that stroke that I was comfortable with.

I do have the BBM heads, with a hydraulic roller cam setup. it's really nice and ridiculously overkill for the task. Blair Patrick did a great job with this for me. He is a true gentleman, and he even put up with my requests to assemble the engine myself after he did all the hard work!

I didn't mean to offend RodKnock - But IN MY OPINION, everything about these cars is emotion. The power to weight ratio is well beyond the limits of what we can fully use on the street, and beyond what the chassis can really fully handle.

If I want to go to the track, I will do better (faster and safer) in a c5 or c6 or c7 corvette. If I want to go somewhere, any other car can take me there more practically. For me, this car is purely emotion.

So, if anyone else wants an aluminum block because it is lighter, or makes their car more valuable to someone, or because they like the aluminum theme, then I 100% support them and, in fact, will openly celebrate their project. this is all about fun and camaraderie. I appreciate all of you as brothers and friends, even though I don't post here too often. (I am one of those unfortunate married individuals who has a wife that does not appreciate my hobby in any way.)

But the original question of this thread was asking our opinions about aluminum blocks. In the previous 5 engines I have built (windsor ford for mustang, cleveland for pantera, small block chevy for 57 bel air, and big block chevy for c2 corvette), i have always used iron blocks for cost and reliability.

Justin