Speedmaster aluminum block

[MadBill]

.. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail..

Good point! It's not exactly the same, but one could dismiss aluminum rods based on their shortcomings (bulk, stretch, always-finite fatigue life...) but any number of high HP combos couldn't survive a pass without them.

[hoffman900]

.. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail..

Good point! It's not exactly the same, but one could dismiss aluminum rods based on their shortcomings (bulk, stretch, always-finite fatigue life...) but any number of high HP combos couldn't survive a pass without them.

In SCCA D-Sports Racer (now Prototype 2), the hot set up are turbocharged 660cc I4 sportbike engines. They make about 330hp or over 8hp/ci. Not super reliable, but they are good for at least 40 minutes (60-80ish miles, or 240 to 320 drag race runs with hard downshifts included) in road racing trim.

Those engines are all aluminum.

[Frankshaft]

.. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail..

Good point! It's not exactly the same, but one could dismiss aluminum rods based on their shortcomings (bulk, stretch, always-finite fatigue life...) but any number of high HP combos couldn't survive a pass without them.

Yes, true. I have seen both gm and dart blocks have the deck pulled away. The dart block just cracked around a cylinder, just under the deck, horizontally. The gm block, the cylinder heads literally fell off the block, it ripped the whole deck off the top of the block.The Dart block was an F3r deal at about 2800hp. The gm block was a gm tall deck 14-71 deal making about 1700.

[statsystems]

.. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail..

Good point! It's not exactly the same, but one could dismiss aluminum rods based on their shortcomings (bulk, stretch, always-finite fatigue life...) but any number of high HP combos couldn't survive a pass without them.

In SCCA D-Sports Racer (now Prototype 2), the hot set up are turbocharged 660cc I4 sportbike engines. They make about 330hp or over 8hp/ci. Not super reliable, but they are good for at least 40 minutes (60-80ish miles, or 240 to 320 drag race runs with hard downshifts included) in road racing trim.

Those engines are all aluminum.

And their size is relatively small. I'm also sure they use nikasil on the bores rather than a sleeve. Since its inline, it's easier to make a casting more rigid (and by rigid I mean less flexible because we all know all castings move around) than a V style block. I'm not sure of stroke length of a liter bike engine, but IIRC they are relatively short and have a rod/stroke ratio close to 2.0 where as even a common small block V-8 has a stroke of 4 inches or more, a bore of 4.155 or bigger with little support between the cylinders because the original architecture was never designed for that much stroke or bore increase.

When you start to think in terms of original design limits and geometry, you can see why in most cases for most of what is discussed here a cast iron block is a better platform until you get to the point where you have exceeded the ability for the casting to accept the increases in bore and stroke and RPM and power and deal with those stresses without fracturing.

I apologize for the run on sentence.

[statsystems]

Well its a good chance i likely have years on you but what the hell. The target moved about as much as you and Lykins's moved it also. If you guys dont like the alloy fine. No sweat off my butt. The point is mild to wild they are working thats what most of us are pointing out. The rail i just pointed out got back to me and said the alloy block was 125 lighter fully prepped. The cast block was 65hp more. That was the equal point. So he needed 65hp more to go the same as alloy. Since then he's added more hp to alloy. He runs full water jacket blocks.

Keep lying to yourself. You keep contradicting yourself. How many times did I say if the idiotic rules mandate that weight is more important that power you have to use as light parts as you can.

Again, your examples don't mean shit to me. I already told you how I see it. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail.

Again, I doubt you have any years on me, or experience, or anything else.

Good for you stats. And a few pages back you said i had arrogance. Seems you take the win. Good on you. If you dont like we talking here simply don't respond. Im sure a ton of us would be happy.no contradicting comments at all just examples. Mild ones to wild. Take it as u like.

It's YOU with the issues. Call me arrogant all you want. Doesn't affect me. You continually prove that you make up things as you go.

No one has said aluminum doesn't have a place. Grow up.

[hoffman900]

Good point! It's not exactly the same, but one could dismiss aluminum rods based on their shortcomings (bulk, stretch, always-finite fatigue life...) but any number of high HP combos couldn't survive a pass without them.

In SCCA D-Sports Racer (now Prototype 2), the hot set up are turbocharged 660cc I4 sportbike engines. They make about 330hp or over 8hp/ci. Not super reliable, but they are good for at least 40 minutes (60-80ish miles, or 240 to 320 drag race runs with hard downshifts included) in road racing trim.

Those engines are all aluminum.

And their size is relatively small. I'm also sure they use nikasil on the bores rather than a sleeve. Since its inline, it's easier to make a casting more rigid (and by rigid I mean less flexible because we all know all castings move around) than a V style block. I'm not sure of stroke length of a liter bike engine, but IIRC they are relatively short and have a rod/stroke ratio close to 2.0 where as even a common small block V-8 has a stroke of 4 inches or more, a bore of 4.155 or bigger with little support between the cylinders because the original architecture was never designed for that much stroke or bore increase.

When you start to think in terms of original design limits and geometry, you can see why in most cases for most of what is discussed here a cast iron block is a better platform until you get to the point where you have exceeded the ability for the casting to accept the increases in bore and stroke and RPM and power and deal with those stresses without fracturing.

I apologize for the run on sentence.

The head gasket is the still the toughest part, but yes, they're small and compact with stuff structures.

I believe the Ford RY45 is really just an aluminum NASCAR spec FR9. Jay might have insight from his friends at Roush on if there are power differences with an equal spec build.

[elwood]

Elrod, if I said it, then prove it. Pretty simple. If I said "aluminum blocks don't work", then show me where. Just cut and paste.

You're welcome to stop by. Right now I have 2 Clevelands, a Clevor, a Boss 302, 3 FE's, and a Modular Ford that are in some degree of building stages.

Too bad that you didn't stop by last month when I had this 1200 hp 556ci BBF pulling truck engine on the stand.

senile too. if you never said something then i suppose that's not what you keep forgetting you said, or is it?

so where was your car parked when this pull motor happened .com? and all this work is in your spare bedroom i guess. did you miss where i said i'm one of those Not An Engine Builder And Probably Only Ever Touched A Couple Blocks In My Life guys (potential customers) that you hold in so much disdain

tell us a couple hundred more times how alloy block builds are inherently down on power to cast iron block builds, make us puke .com

[Steve.k]

Keep lying to yourself. You keep contradicting yourself. How many times did I say if the idiotic rules mandate that weight is more important that power you have to use as light parts as you can.

Again, your examples don't mean shit to me. I already told you how I see it. There is a time when aluminum becomes mandatory. Anything with a blower making 3.5 HP/CID will need an aluminum block. The original architecture won't support that much load. The block has to flex at that point. If it doesn't, it will fail.

Again, I doubt you have any years on me, or experience, or anything else.

Good for you stats. And a few pages back you said i had arrogance. Seems you take the win. Good on you. If you dont like we talking here simply don't respond. Im sure a ton of us would be happy.no contradicting comments at all just examples. Mild ones to wild. Take it as u like.

It's YOU with the issues. Call me arrogant all you want. Doesn't affect me. You continually prove that you make up things as you go.

No one has said aluminum doesn't have a place. Grow up.

And what exactly was that i made up?You tell me genius!

[blykins]

Elrod, if I said it, then prove it. Pretty simple. If I said "aluminum blocks don't work", then show me where. Just cut and paste.

You're welcome to stop by. Right now I have 2 Clevelands, a Clevor, a Boss 302, 3 FE's, and a Modular Ford that are in some degree of building stages.

Too bad that you didn't stop by last month when I had this 1200 hp 556ci BBF pulling truck engine on the stand.

so where was your car parked when this pull motor happened .com? and all this work is in your spare bedroom i guess. did you miss where i said i'm one of those Not An Engine Builder And Probably Only Ever Touched A Couple Blocks In My Life guys (potential customers) that you hold in so much disdain

Wow dude. Is this the result of rage or methamphetamine?

[elwood]

what do you call a engine builder, machinist, tuner, over-all automotive self declared God and superhero with a boo boo fingy that works out of his trunk with a cell phone?

[Dave Koehler]

For crying out loud, will you children stop it.
13 pages of name calling and nothing learned.
Go get a Snickers.

[lefty o]

For crying out loud, will you children stop it.
13 pages of name calling and nothing learned.
Go get a Snickers.

best post in the whole thread!

[statsystems]

For crying out loud, will you children stop it.
13 pages of name calling and nothing learned.
Go get a Snickers.

Even that won't help. You have people who are professional argument makers. You can post your real world experience, backed up by professional people no less that Larry Meaux and Darin Morgan and they still want to tell you how stupid you are because so and so runs his car on a dirt bull ring with a stupid weight limit blah blah blah. Or how an inline 4 can be compared to a V-8 that has had its architecture blown out beyond what any engineer ever had in mind when designing it.

I mean really...can any thinking, intelligent man not see the folly in such thinking? Let's take a liter 4 cylinder, and increase its bore, stroke and RPM increased in an equal amount to what the standard American V-8 has been and THEN tell me how good the aluminum is.

Not one of us has said aluminum doesn't have a place in engine blocks. If you are under 1000 HP and N/A and if your stupid rules don't allow flyweight shit the cast iron will beat it every time.

I had a customer back in 1998 with a dragster. I begged him not to buy an aluminum block for his car. He figured weight was better than HP. It wasn't. Since it was a rear engine car, he had to add weight to the car to get it to hook and he gave up power.

He stepped on his own dick. The car never performed like he thought it would, but did exactly what I told him it would. A couple seasons later he parked the car.

[user-30257]

For crying out loud, will you children stop it.
13 pages of name calling and nothing learned.
Go get a Snickers.

Even that won't help. You have people who are professional argument makers. You can post your real world experience, backed up by professional people no less that Larry Meaux and Darin Morgan and they still want to tell you how stupid you are because so and so runs his car on a dirt bull ring with a stupid weight limit blah blah blah. Or how an inline 4 can be compared to a V-8 that has had its architecture blown out beyond what any engineer ever had in mind when designing it.

I mean really...can any thinking, intelligent man not see the folly in such thinking? Let's take a liter 4 cylinder, and increase its bore, stroke and RPM increased in an equal amount to what the standard American V-8 has been and THEN tell me how good the aluminum is.

Not one of us has said aluminum doesn't have a place in engine blocks. If you are under 1000 HP and N/A and if your stupid rules don't allow flyweight shit the cast iron will beat it every time.

I had a customer back in 1998 with a dragster. I begged him not to buy an aluminum block for his car. He figured weight was better than HP. It wasn't. Since it was a rear engine car, he had to add weight to the car to get it to hook and he gave up power.

He stepped on his own dick. The car never performed like he thought it would, but did exactly what I told him it would. A couple seasons later he parked the car.

I haven't had that problem, I have built hundreds of aluminum engines. And had a few back to back te sts. The most I lost was about 1.5 %.

I would never build a 12" deck height 5.100" bore engine out of cast. The block alone would weigh probably 7-800lbs. Maybe your issues were ring seal. Fix that don't blame the alloy.

What's funny is even the LS engine. I have some the same 408 combo in iron and aluminum and they make the same power NA/Boost within 1-2% I just don't see the huge loss you do. I guess I'm the only one.

[MadBill]

Be interesting to compare blowby in CI vs. AL versions of the same engine. Maybe the latter would benefit more from TS Gapless® rings...
(Woops! Another hot-button topic... )