What's the appeal of an aluminum engine block?

[olddog]

Originally Posted by RodKnock

A few years ago, Jay Brown published a nice book called the FE Intake Comparo or something like that. I bought that book. So, a nice book with all the data proving the point (cast iron vs. alloy) would be fanatastic.

Also, if the result is 15-30 HP difference then I'd argue "WTF" that's it? All this chatter for a statistically insignificant amount of HP? I'd assert HP would/should be eliminated as a benefit or positive when choosing a cast iron block over alloy.

Honestly, we have maybe a dozen owners here of alloy blocks that don't have any reliability issues and assuming the extra HP is 15-30, which to me is insignificant, then the only reasons you would chose a cast iron block is: a) price, b) you want your Cobra replica to have a vintage block, maybe correctly dated, for "originality" purposes, ridiculous and nonsensical as that concept may be and c) the desire to add 125 lbs for no apparent reason.

I think Brent's reply should be:
So you want to spend $2500 to loose 125 lb and consider the 30 Hp loss insignificant. At a 4:1 weight to Hp ratio a 30 Hp loss is equivalent to a 120 lb gain in weight. So your willing to spend $2500 for an overal gain of 5 less pounds to accelerate? I could use a good laxative the night before a race to achieve the same results.

I have to be honest:
The smart ass comment above was to make a comical point. Without the emoticons, it looks like I'm piling on. The point is true if drag racing. In the twisty turns, the hole 125 lb matters and you cannot apply much power in a corner. However accelerating away we're back to the 5 less pounds to accelerate thing.

[jhv48]

Originally Posted by olddog

I think Brent's reply should be:
So you want to spend $2500 to loose 125 lb and consider the 30 Hp loss insignificant. At a 4:1 weight to Hp ratio a 30 Hp loss is equivalent to a 120 lb gain in weight. So your willing to spend $2500 for an overal gain of 5 less pounds to accelerate? I could use a good laxative the night before a race to achieve the same results.

I have to be honest:
The smart ass comment above was to make a comical point. Without the emoticons, it looks like I'm piling on. The point is true if drag racing. In the twisty turns, the hole 125 lb matters and you cannot apply much power in a corner. However accelerating away we're back to the 5 less pounds to accelerate thing.

I think that says it all. We should let the horse limp away now that the flogging has ended.

[RodKnock]

Originally Posted by olddog

I think Brent's reply should be:
So you want to spend $2500 to loose 125 lb and consider the 30 Hp loss insignificant. At a 4:1 weight to Hp ratio a 30 Hp loss is equivalent to a 120 lb gain in weight. So your willing to spend $2500 for an overal gain of 5 less pounds to accelerate? I could use a good laxative the night before a race to achieve the same results.

I have to be honest:
The smart ass comment above was to make a comical point. Without the emoticons, it looks like I'm piling on. The point is true if drag racing. In the twisty turns, the hole 125 lb matters and you cannot apply much power in a corner. However accelerating away we're back to the 5 less pounds to accelerate thing.

Pond prices his alloy and cast iron blocks exactly the same. From memory, BBM charges $1,000 more for an alloy block. At the time, my Shelby block was $1,000 extra. But Shelby has probably priced themselves out of my engine build, if I were in the market today.

And as I said earlier, I can compensate for the alleged loss of 15-30 HP in the engine build or even a chassis dyno tune. It's awfully difficult to lose 125 lbs from my Kirkham. And it's not an either/or proposition for me. I want both, the reduced weight and the extra HP from the build and the chassis dyno tune.

[olddog]

Originally Posted by RodKnock

And as I said earlier, I can compensate for the alleged loss of 15-30 HP in the engine build or even a chassis dyno tune. It's awfully difficult to lose 125 lbs from my Kirkham. And it's not an either/or proposition for me. I want both, the reduced weight and the extra HP from the build and the chassis dyno tune.

Now that is pure logic. Hard to argue against that, well maybe a fool would.

Glad you are still talking to me.

You are correct, for what you have and do you need the aluminum FE. However, for most of the Cobra owners I have met at the London car show, I think Brent is also correct in that they really do not have a need for an aluminum FE. Unfortunately for Brent most people do not understand the difference between a need and a want.

[RodKnock]

Originally Posted by olddog

Glad you are still talking to me.

Hey Guys, this conversation is like sitting around a friend's basement shooting the breeze and arguing. Back in the days, we used to argue and rag on each other about our cars, sports teams, looks, significant others, etc. There's no malice or anger here.

[Dimis]

Originally Posted by olddog

Now that is pure logic. Hard to argue against that, well maybe a fool would.

Yep Olddog, I'm a fool choosing to entertain RK further, when I know he'll keep playing till he gets the last work, even if it moves off topic.

Watch...

Originally Posted by RodKnock

Oh Dimis,

1. I could re-jet and tune my carb on a chassis dyno and get 15-30 HP. Where would I drop 125lbs with my Kirkham?

2. Yea, reliability is/was a concern. Somewhere in the last 15 or so pages somebody (not me) mentioned "power, reliability and quality." That wasn't me. And the other complaint was the alloy block casting was flexing, expanding, contracting and popping at the seams, whereas the cast iron block was rock steady and never leaks.

3. My rule of threes? I think it was Patrick and others talking in threes. I was only pointing out the anomaly.

Hey RK,

1. I know you did the maths and agree with me, that's why you changed he subject to tuning carbs. What if carbs are already tuned and tuned alike 15-30hp as you stated, for engines that are commonly built between 400-600hp, like in our cobras represents 5% +/- of their power. Correct?
How can you argue that 5% is insignificant, yet argue that 5% of your car's weight is?

2. Nah, reliability was never raised by the builders, unless I missed it. Show me please. It was only raised by third parties who seemingly misinterpreted what the builders were saying. True?

3. You first raised the rule of 3s. Pat just explained the reason for your observations. Yes?


Now, just so i don't get confused buddy, please just answer "yes" or "no" next to each point. Then you can elaborate on your reasoning

[patrickt]

Originally Posted by Dimis

Now, just so i don't get confused buddy, please just answer "yes" or "no" next to each point. Then you can elaborate on your reasoning

Haaa, asking RodKnock to just answer "yes" or "no" is like asking Ellie not to pass gas after her third plate of turkey. You're just wastin' your breath... and you'd be better off holding it.

[Dimis]

Originally Posted by patrickt

Haaa, asking RodKnock to just answer "yes" or "no" is like asking Ellie not to pass gas after her third plate of turkey. You're just wastin' your breath... and you'd be better off holding it.

Yes sir. I'm aware.
Let see who has more self control. RK or Ellie.

[RodKnock]

Originally Posted by patrickt

Haaa, asking RodKnock to just answer "yes" or "no" is like asking Ellie not to pass gas after her third plate of turkey. You're just wastin' your breath... and you'd be better off holding it.

Answer "yes" or "no"? What is this? A deposition? It all depends on what your definition of "is" is?

[patrickt]

Originally Posted by RodKnock

Answer "yes" or "no"? What is this? A deposition? It all depends on what your definition of "is" is?

No. In a deposition we let you talk as long and as winding as you'd care to go. It's when you're on the stand that we try and pin you down to yes or no.

[fordracing65]

Originally Posted by RodKnock

Pond prices his alloy and cast iron blocks exactly the same. From memory, BBM charges $1,000 more for an alloy block. At the time, my Shelby block was $1,000 extra. But Shelby has probably priced themselves out of my engine build, if I were in the market today.

And as I said earlier, I can compensate for the alleged loss of 15-30 HP in the engine build or even a chassis dyno tune. It's awfully difficult to lose 125 lbs from my Kirkham. And it's not an either/or proposition for me. I want both, the reduced weight and the extra HP from the build and the chassis dyno tune.

Pond block $5695. BBM block $4800. Aluminum.

[RodKnock]

Originally Posted by fordracing65

Pond block $5695. BBM block $4800. Aluminum.

Is the price for a BBM cast iron block $3,500?

[fordracing65]

Originally Posted by RodKnock

Is the price for a BBM cast iron block $3,500?

I was comparing aluminum. Nobody with a Kirkham is buying iron.

[rodneym]

Originally Posted by fordracing65

Nobody with a Kirkham is buying iron.

While most Kirkhams probably have ally blocks, half of the ones I know personally are iron.

[RodKnock]

Originally Posted by rodneym

While most Kirkhams probably have ally blocks, half of the ones I know personally are iron.

100% of the Kirkham's that I personally know of have aluminum blocks. I only personally know of my Kirkham, but the % sounds impressive.

[fordracing65]

Originally Posted by rodneym

While most Kirkhams probably have ally blocks, half of the ones I know personally are iron.

Probably built before aluminum was available. Lol. Are they faster or slower than aluminum blocks. Ask them.