What's the appeal of an aluminum engine block?

[blykins]

I'd like to hear a chassis guy's thoughts on how the aluminum block actually affects the C/G and handling of a Cobra. The engine sits much further back in a Cobra than a normal vehicle. IMO, you'd only be able to tell the difference if you were really giving it grief on a road course. And at that point, the entire engine build and car setup should be changed.

Another "con" of an aluminum block build that I failed to mention above, is that they are harder to get them sealed up. Since the blocks "move around" so much with heat expansion, it can cause issues with gasket sealing.

[66gtk]

I'm with you Brent. As a business man you are in charge and your reputation is all you have. Without it you don't have a business or customers. If somebody insists on doing something you feel will fail you have the right to refuse it. No reasonable amount of money or written disclaimers are enough to offset the power of an angry customer who trashes your name across the internet because he feels he was taken to the cleaners. It doesn't matter if you warned him or had him sign off that you can't back the decision - These people only hear what they want to hear and believe what they want to believe. They are toxic to your business. There will always be somebody "cheaper" and somebody who will gladly accept money who will agree to to the job. Let them have that customer if you can't convince the customer that what you are offering is "better".

A couple years ago I had a car with a Pond aluminum FE block. I've had several with cast iron blocks. I could care less about if I had an aluminum or Iron block. There are so many more important variables in an engine build that make the car more enjoyable to drive. I was able to command a higher price for the Al block car for some reason. I think it's all perceived value - no different than people paying more for a CSX replica than an equally equipped KMP. I had a potential customer who missed out buying my car with the Al block and he's regretted it since and now has me looking for another one for him to buy. I've offered him several without the Al block and he now is not interested in them. Reason? I haven't heard one. I think it's just bragging rights.

[moore_rb]

Originally Posted by 66gtk

I think it's all perceived value - no different than people paying more for a CSX replica than an equally equipped KMP.

^^^^ Yeah, that....

[blykins]

66gtk, Thanks for the words.

I never let an engine leave here with a known issue, even if it requires that the engine be torn completely down, machine work involved, etc. So with that being said, the customer in this instance would never have the opportunity to be upset or angry....but it would just cost me time and money to repair it before it left.

[blykins]

If I were building such a high level car as a KMP or CSX, where originality is certainly a big part of it, I'd want a cast iron block. JMO though.

[Three Peaks]

A lot of very valid points here. When I had my business, (electrical contractor) the one thing I tried hardest to protect was my reputation. With substandard parts in the mix and a demanding customer, you can't be careful enough to avoid every pitfall. And there is always that customer that doesn't understand anything but money and schedule so no excuse in the world will smooth out the lack of trust when a problem comes up.
I worked for free many times to take care of an issue that came up at the last minute so we could meet a schedule or keep a customer happy. Most times the customer never even was aware we did it so he was blissfully happy his project was done on time and on budget.

However, when I have work done I try to use the most experienced and referenced people I can find. For things like engine work I have enough experience to know when I guy is BS'ing me or not. If a reputable builder in just about any field tells me they won't do something because there are issues that aren't worth the effort, they get my attention. When a pro tells me to buy something cheaper, but better, I tend to listen up to his recommendations and ask lots of questions so I understand his reasoning. If it is sound I will usually use that pro for my work as I like to work with honest people. The few times I've disregarded good advice I've paid the price almost every time.

Long story short, if your customers trust you they will strongly consider your recommendations and reasoning. If they don't, no amount of reasoning will sway them around and they are only looking for the bragging rights, IMHO.

As far as the weight issue, I've done a bit of studying and the cast iron FE blocks fully built out are really only about 100-150 lbs heavier than the 351W cast iron blocks built out. With the weight bias in these cars that only totals out to approximately half that additional weight on the front of the car. Not many guys who are street or even autocross drivers are going to notice that amount of difference given proper springs to compensate for the weight and proper set up and alignment on the car, IMHO.

Bob

[YerDugliness]

While I've never had an aluminum block, my understanding is that reducing weight has influence on more than just power:weight ratio...braking and handling are enhanced when vehicle weight goes down.

When I first got my replica (bought it used, but in running condition) the previous owner had not adjusted the idle speed and it was idling at about 1500 RPM...every time I tried to make a turn on a road that had some sand or gravel on it, the vehicle "slid", for lack of a better descriptor. As my engine is all iron, I just attributed that to all the weight in the front of the car (my engine does not sit in the front "cradle" as far back as most, there is about half of the bell-housing visible as I view the back of the engine).

Perhaps the best advice I have gotten was something to the effect of: "Spend your $$ on good brakes and lightening the car, they'll never catch you!

I must admit that as I develop plans for the Clevor build, I always envision it with an all-aluminum block...perhaps that is not the best of ideas?

Cheers!

Dugly

[blykins]

Originally Posted by YerDugliness

While I've never had an aluminum block, my understanding is that reducing weight has influence on more than just power:weight ratio...braking and handling are enhanced when vehicle weight goes down.

When I first got my replica (bought it used, but in running condition) the previous owner had not adjusted the idle speed and it was idling at about 1500 RPM...every time I tried to make a turn on a road that had some sand or gravel on it, the vehicle "slid", for lack of a better descriptor. As my engine is all iron, I just attributed that to all the weight in the front of the car (my engine does not sit in the front "cradle" as far back as most, there is about half of the bell-housing visible as I view the back of the engine).

Perhaps the best advice I have gotten was something to the effect of: "Spend your $$ on good brakes and lightening the car, they'll never catch you!

I must admit that as I develop plans for the Clevor build, I always envision it with an all-aluminum block...perhaps that is not the best of ideas?

Cheers!

Dugly

Here's the thing.....Dart and Ford Racing make a lot of aluminum Windsor blocks. High quantity. I have a little more faith in them just because of the number of blocks that are sold and the fact that a very large company/foundry is casting them.

With that being said, a Dart aluminum block sells for about $6000. A For Racing block sells for $4200. Considering that you have to pay that much for one and you will actually make less horsepower with an aluminum block, if you're not shooting for a specific curb weight or racing in a class, my advice would be to pass....

[YerDugliness]

Originally Posted by blykins

Here's the thing.....Dart and Ford Racing make a lot of aluminum Windsor blocks. High quantity. I have a little more faith in them just because of the number of blocks that are sold and the fact that a very large company/foundry is casting them.

With that being said, a Dart aluminum block sells for about $6000. A For Racing block sells for $4200. Considering that you have to pay that much for one and you will actually make less horsepower with an aluminum block, if you're not shooting for a specific curb weight or racing in a class, my advice would be to pass....

Thanks for that info, Brent! It makes sense to go iron if that makes more HP, I wasn't aware that was the case.

That makes my future plans a bit less demanding. I can get significant lightening up front with alloy heads, water pump, etc. My car is not a racer at all, more accurately a daily driver. With the 1989 block in my replica being one of the more desirable of the 5.0s (roller lifters, hypereutectic pistons) I can see much more clearly the build parameters now.

Cheers!

Doug

[Jus Cruisin]

I'm not going too try to replicate an original Cobra with my probable car choice. I had an FE engine in a 1967 Fairlane that I built to look like a 427 car. This will be my next Ford powered toy after a few Chevy powered cars. This time it'll 427 small block. Dart cast iron.

[RodKnock]

1. Big blocks are heavy and lightening the front end to make the car more nimble was certainly the main factor in choosing an aluminum block.

2. There was a certain symmetry with having an aluminum block in an aluminum body with a billet aluminum suspension and wheels and an alloy differential.

3. Back in 2008, there wasn't a shortage of aluminum blocks and, from memory, Genesis was one of the only producers of new iron FE blocks and they were having casting/porosity issues with their blocks at that time.

4. The price difference was relatively negligible. New FE blocks were roughly $3,500-$4,000. The Pond alloy block was $4,000-$4,500. And the Shelby alloy block $5,000-$5,500. I can't remember the figures exactly, but that's ball park.

5. The rumor mill or "I had heard" that the mating of alloy heads to the cast iron block caused metallurgical issues, which in turn caused sealing problems and oil leaks. And most sports cars today have all alloy engines, so that was somewhat comforting at the time.

6. Bragging rights. Yes, we all have egos.

Would my decision be different today? Maybe, even probably, depending on various circumstances like shortages, block casting problems, etc. Today, I'd be more likely to choose a cast iron block than 8 years ago.

[Dimis]

For me, these cars are ALL about the engine...

I could have paid less for a car that was faster, and more reliable, and more durable, and more comfortable... but meh, where's the joy in that?


Brent, to answer your question as per my decision making process, in order of priority for me:

1. The engine HAD to match the car.
If I had bought an SPF or ERA I'd have chosen different engines, but with an Aluminium car, Alu Body, Alu billet bits everywhere, etc, there was really only one obvious option, an all Alu engine.


2. Weight - Is the enemy of anything that needs to move and accelerate. It's what makes Lotus, Lotus, and Porsche, Porsche. If its good enough for car manufactures to delete carpet, radios, door handles, and change glass to polycarbonate, or steel to Aluminium, and then to carbon fibre, so be it. Designers and Engineers bust a nut trying to shave ounces, so dropping 100lbs by using an Alu block, is a no brainier, particularly 100lbs on a sub 2000lbs car. The fact most all probably aren't able to tell the difference, is NOT relevant, if the placebo is.
My BMC road race bike weighs 6kgs (just over 13lbs). I can feel and tell the difference when I ride it compared to my 6.8kg (15lbs) road bike, my Strava times aren't that much different, but the pleasure off riding the BMC is just blissful. It's not even a full 2lbs difference.


3. Advancement / Progression - The automotive manufacturing world has followed this advancement and progression with intakes and heads. Iron out, Alloy in, and before you know it to Carbon or Carbon fibre wherever possible. Why stop at just heads and intake?


4. Durability - If you recall we discussed this at the time, and the truth is for a car that sees so few miles and heat cycles per year, opting for the more exotic, fully optioned specs, was a no brainier. Remember, I twisted your arm to upgrade to the forged SCAT crank, and the titanium bits. My car will never see 100k miles, the world would have run out of oil 3 times over by then. Further, AFAIK Alu blocks have been beat on and tested in many high end motorsports. So theoretically, any durability quotient should have well and truly be met. The fact they may not produce the same max HP wasn't irrelevant. The car is grossly overpowered as it is... Thanks for that by the way!


5. It was new and pretty... meaning we didn't have to go hunting in graveyards for a solid but seasoned block. Nor be held to ransom (time and money) for a virgin 427 Side Oiler that had been sitting all these years just waiting for me, if it even exists.


I hope that helps with your survey

[patrickt]

Originally Posted by Dimis

I hope that helps with your survey

... and if the engine had exploded in to a supernova on its first dyno run?

[Large Arbor]

I bought the car which had an aluminum block.

Having noted that, I have noticed two significant advantages. 1) They cool off really quickly which is great in hot weather. 2) the weight savings is significant.
3) if you have a good engine builder the risks can be mitigated.

Phil

[jhv48]

Originally Posted by Large Arbor

3) if you have a good engine builder the risks can be mitigated.
Phil

And away we go!

[Dimis]

Originally Posted by patrickt

... and if the engine had exploded in to a supernova on its first dyno run?

Well, it really could have... but it could have if iron too.

In the end I trusted the guy who put it together... It turned out ok.

At the same time if it went bang, I guess Brett (and or I) would have had to find the time, money and energy to chase up the supplier... Not easy in a one man band. So I understand his headache.

Despite there being plenty of fat factored into the price, eg: when you pay the manufacturer $5K for recycled coke-cans in the shape of a block, or $2K for heads, it doesn't mean the manufacturer would be prepared to stand by their faulty product or workmanship. Its worse again with NOS parts. NO chance of a warranty there.

Originally Posted by blykins

I have made the decision to not accept any more all-aluminum FE build orders.

Originally Posted by blykins

As some of you know, aftermarket FE blocks have been non-existent this year. I've been waiting on blocks since February and still have not received any. Foundries have changed, designs have changed, and until things settle down

By the way not accepting any more orders is just prudent and practical in light of the fact blocks are just not available. I didn't see him say he wont ever build them again in the future.

[blykins]

Just to address those...

These days the Pond aluminum block is $5600 and up. Shelby is about $1000 higher.

BBM iron block is around $3500 I think.

Absolutely no issue whatsoever with running aluminum heads on cast iron blocks. Zero. There are actually more chances of leaks with the all-aluminum FE engines than the cast iron/aluminum pieces. Plus, I recommend that all my all-aluminum customers run Moroso Ceramic Seal through the tank on an initial install. Don't have to do that on a "hybrid" engine.

A lot of your OEM combinations are all-aluminum. However, they have OEM quantity, OEM manufacturing, and OEM foundries behind them. Big difference.

Personally, knowing all that I know, I wouldn't consider an aluminum block a bragging right, but I could see where it could be taken that way. Same way as bragging about having a "6-speed".

By the way, RK, this post wasn't an argument to your points, but just trying to clarify some things out there that could be really considered rumors, as you call them.

[RodKnock]

Originally Posted by blykins

Personally, knowing all that I know, I wouldn't consider an aluminum block a bragging right, but I could see where it could be taken that way. Same way as bragging about having a "6-speed".

By the way, RK, this post wasn't an argument to your points, but just trying to clarify some things out there that could be really considered rumors, as you call them.

No worries.

While you, as an engine builder, don't think running an aluminum block is a bragging right, the consumer still does. And when you go to sell your Cobra, the buyer's perception is that the alloy block is better. Why? It costs more and it removes about 100 lbs from the front end. Until buyer's perceptions change, it will continue to be an issue when you go to sell your Cobra.

Are the OEM foundries different from the foundries that cast the alloy FE blocks? There can't be that many foundries left in our country that can make these things anymore. The FE block has been around for 50 years, not much has changed, so it's not like these foundries are inventing a new iPhone or the newest flu vaccine.

[Mark IV]

Originally Posted by blykins

A lot of your OEM combinations are all-aluminum. However, they have OEM quantity, OEM manufacturing, and OEM foundries behind them. Big difference.

Personally, knowing all that I know, I wouldn't consider an aluminum block a bragging right, but I could see where it could be taken that way. Same way as bragging about having a "6-speed".

Brent,

The "OEM" guys are using pressure cast aluminum in permanent molds with foam void cores, a big difference from gravity cast, sand pattern castings. The ability to control core shift, etc. is much greater with high dollar production means.

[cycleguy55]

I spent 22+ years working for IBM and one of its wholly-owned subsidiaries, and I can tell you IBM (and the subsidiary I worked for) did a risk assessment on every substantial piece of work it bid on. Each of those risk assessments produced a risk rating, with appropriate risk 'premiums' and contingencies applied to those bids or proposals. Having said that, there were situations where the risk assessment produced an extreme or unacceptable risk rating. Under those situations IBM would choose not to bid.

While Brent is dealing with a completely different set of circumstances, products, etc., he's performing his own risk assessment on the business he chooses to accept. If his experience (one of the factors in IBM's risk assessment) tells him the use of aluminum blocks (analogous to IBM's use of 3rd party products) produces an unacceptable risk rating, then he can well choose to decline the work. I completely understand - especially after reading his responses and rationale in this thread.