What's the appeal of an aluminum engine block?

[rodneym]

I'm all aluminum with my FE and I thought I had a rear main leak on top of an oil pan leak.
Then I got the Kirkham billet pan.
Haven't seen a drop of oil on the floor in almost 1,000 miles. And yes, Pat, there's oil in the engine
And while I'm not a race car driver, it does gets exercised enough to embarrass every one of the haughty cars that have wanted to play. Granted, the lines were always "somewhat" straight

[RodKnock]

Originally Posted by rodneym

I'm all aluminum with my FE and I thought I had a rear main leak on top of an oil pan leak.
Then I got the Kirkham billet pan.
Haven't seen a drop of oil on the floor in almost 1,000 miles. And yes, Pat, there's oil in the engine
And while I'm not a race car driver, it does gets exercised enough to embarrass every one of the haughty cars that have wanted to play. Granted, the lines were always "somewhat" straight

See rodneym^^^. Uh let's ask rodneym about "reliability, power output and quality". He has an all aluminum twin Paxton blown FE, IIRC. And he's driven his car 5,000-10,000 miles. I don't remember him complaining about "reliability, power output and quality." We both had our engines built by Tom Lucas here in CA. While I haven't driven as many miles, I think my engine has been quite reliable with 600+ HP, no leaks, etc.

Do cast iron blocks make more HP? Everyone seems to think so, Barry and Brent do too. But if folks believe that a 125 lbs of block weight isn't a big deal (5.5% of my Kirkham), then why does a few extra HP with a cast iron block?

[blykins]

Blair Patrick will also tell you that an iron block will make more horsepower without the "fickle-ness" of an aluminum block. He's not a fan either.

In my mind the horsepower difference between the cast iron block and the aluminum block would almost make up for the weight difference in a straight line, 1/4 mile type deal. A 20-hp difference is a .1 ET difference in the 1/4.

There's not that many corner-carvers on here, so I don't know how justified the loss of weight is for most Cobra owners. I think, in my opinion, that to most buyers, "all-aluminum" is a buzz-word, just like "billet" or "roller" or "forged".

I wish Richard Hudgins was still active here. I'd like to have a true chassis guy's input on how much the weight difference affects the handling of a Cobra and at what point the "average" driver would be able to tell it.

[RodKnock]

Originally Posted by blykins

Blair Patrick will also tell you that an iron block will make more horsepower without the "fickle-ness" of an aluminum block. He's not a fan either.

In my mind the horsepower difference between the cast iron block and the aluminum block would almost make up for the weight difference in a straight line, 1/4 mile type deal. A 20-hp difference is a .1 ET difference in the 1/4.

There's not that many corner-carvers on here, so I don't know how justified the loss of weight is for most Cobra owners. I think, in my opinion, that to most buyers, "all-aluminum" is a buzz-word, just like "billet" or "roller" or "forged".

I wish Richard Hudgins was still active here. I'd like to have a true chassis guy's input on how much the weight difference affects the handling of a Cobra and at what point the "average" driver would be able to tell it.

"In my mind", if I were in the market, I'd find a competent confident engine builder who can build an all aluminum FE, because weight is important. And there are thousands of alloy blocks on the road and I haven't heard many, if any complaints. I haven't heard anyone mention alloy blocks being fickle either. And at least 8 alloy block buyers here in this thread said weight was an important factor when building their engine.

As for differences in HP between the two, post some data dump sheets of two equal engines with the only difference being the block.

Lastly, on my way to Starbucks for my morning mocha, there are two sharp turns, and I can feel the difference.

[patrickt]

Originally Posted by RodKnock

I haven't heard anyone mention alloy blocks being fickle either.

I didn't even skin a knuckle on my build. Although I do vaguely remember the builder saying something had broken off, it was a PITA to get out, and that's why it would be slightly delayed getting over to the ERA boys, but, again, no skin off my nose, knuckle, butt, toe, etc.