big cube small blocks?

im wondering how many cubes i can get out of a stock 400 sbc and how. it probably wont ever get done...just curious

434 is about as much as you can squeeze... .030 overbore and 4" stroke crank.

Bret

well what sbc is those 454 and 498's based off?

The aftermarket blocks from dart and World products can be had in 454. I would assume you would have to use a deck plate to get the 498, just speculation though.

Sonny's has done a 502 sbc but it's proprietary- no instructions on exactly what they did to pull it off. Anything over 454 and the price jumps dramatically, I would expect. I'm sure they used an aftermarket block, or at least something with a tall deck and thick wall casting.

They moved the bore centers with sleeves and ran a stupid large bore in a SBC.... probably around a 4.500-4.550" bore center.

Bret

so where would i get a 4 inch stroke crank? what rods would i have to use? im kinda wondering price now. would be fun to say "yeah its just a little small block" but have 434 cubic inches under the hood :D

eagle makes them

So,,

What would be a great pumpgas Street/Strip setup at 6800 rpm max and good ole ODBI ECM?

434 Dart at 12:1 compression
Some Honking 300+ CFM Aluminum heads - Brodix 18
Reasonable EFI friendly solid roller cam

Just need to figure out how to get an opti signal for LTCC system.

Me want one!

Just about every crank maker out there offers a 4.0" stroke crank these days. Call and ask if you're really curious.

You can build a 454 small block on an old block but the block has to be perfect. If you had 10 blocks to check, you might find one that'd make it. Otherwise, 434+ ci small blocks are the realm of aftermarket blocks. Most every aftermarket block will go 4.2" on the bore and the spread pan varieties will accomodate a 4.125" stroke crank with no clearance work.

You could go 4.25" stroke but once these engines start to become "over square" getting the power out of them becomes alot tougher. If you plan on building a 427-434 on a factory block, make sure you use the right rods. Lunati, Crower and Oliver all have rods with great stroker clearance. Don't know much about the less expensive Eagles and such listed as "stroker" rods. That's where it pays to find a builder who has experience building this kind of engine.

-Mindgame

Why ya all stuck on cubes? Cubes in a small block just cost money, money that most don't have, and that they should be spending on what actually makes power.

700+ HP is doable on a 383 with 23° heads... unless that's not enough don't worry about huge cubes, and huge strokes.

Bret

700+ HP is doable on a 383 with 23° heads... unless that's not enough don't worry about huge cubes, and huge strokes.

Bret

Bret,

I'd love to compile a list of all the 700+ hp 383's with 23º heads from this forum. That list would probably entail a single digit from the binary system. :)

Especially if we narrow the field to NA. For nitrous builds looking to 700+.... why spend all the money?

-Mindgame

True...

But with the raised port 23° stuff out there, big power N2O motors are much easier to build, and save cost in headers, pistons etc... 15°, 18° and SB2 stuff all runs so much more money for the customer in the end.

Bret

My intention with cubes is... more cubes... less fuel requirements and sometimes less cam requirements to make the power.... which makes it more of a livable car....

Why did gm went with a 427 for a measly 505hp?????

Don't forget, a bigger engine needs more air. Price out some heads that flow in the 300+ range or you'll just be choking the big engine.

Those really big small blocks use an aftermarket tall deck block to get the extra cubes. 434 is common and 454 is considered extreme. Anything bigger than that and you might as well build a BBC for half the cost.

Why ya all stuck on cubes?


'Cause cubes are COOL, you friggin' jabronie!:D
Yeah, yeah; I know...a 396 ISN'T SMALL! :rolleyes:
:D

anything less than a 427 is small.... 427 is.... the size...

In a quest for a very streetable 500 RWHP NA motor, on pump gas, on stock ECM, don't those cubes begin to make sense? I certinly agree a great 383 might get you there but won't it be a bit high strung for a street motor?

Steve

Bret,

I'd love to compile a list of all the 700+ hp 383's with 23º heads from this forum. That list would probably entail a single digit from the binary system. :)

Especially if we narrow the field to NA. For nitrous builds looking to 700+.... why spend all the money?

-Mindgame

We'll let you know MG, Im trying to be # 0 on that list.:)

So,,

What would be a great pumpgas Street/Strip setup at 6800 rpm max and good ole ODBI ECM?

434 Dart at 12:1 compression
Some Honking 300+ CFM Aluminum heads - Brodix 18
Reasonable EFI friendly solid roller cam

SABLT194, you and I are thinking along the same lines my friend :D


Nick

$10,495 and you get a warranty. 610 hp at 6,400 rpm and 584 lb-ft at 4,500.

http://www.worldcastings.com/new/images/features/113_0307_454_02_s.jpg

Rich

Well food for thought.... I would not recommend much over 500lbft tq in a stock 400 block wich isnt hard to acheve. The 400 blocks suffer from poor cyl wall thickness when bored. My first .030" over block cracked a cyl wall vertically. I then replaced the block with one we did a partial water jacket fill on(not so good on a street motor). With no other changes other than fresh rings and bearings the motor picked up a tenth proving that in the first block, ring seal was a little less than desired. Unfortunatly that block also failed it broke 3 main caps (pictures here) http://hometown.aol.com/kwik39/myhomepage/auto.html It also does not take into consideration the amount of block prep on a stock block The block in the pictures required a bit of grinding with a stock stroke crank (3.75") and 6" eagle rods. A 4" would only make clearancing it more of a challange. I am not saying it can't be done...only IMO it would be better to start with an aftermarket block. My new Dart block was dropped of this week :D hopfully the new 18* heads will be done this weekend!

That list would probably entail a single digit from the binary system.


Couldn't we make that Hex? That way I could at least hope for an F. ;)

Couldn't we make that Hex? That way I could at least hope for an F. ;)

No sir, I'd have to map you to binary. :D

:)

-Mindgame

$10,495 and you get a warranty. 610 hp at 6,400 rpm and 584 lb-ft at 4,500.

http://www.worldcastings.com/new/images/features/113_0307_454_02_s.jpg

Rich
that puts the 472 hemi at $14,000 525horse 540tq to shame. :shame:

that puts the 472 $14,000 525horse 540tq engine to shame. :shame:

Wow, where'd you see that anchor?

-Mindgame

Wow, where'd you see that anchor?

-Mindgame

try the mopar catalog

try the mopar catalog

He edited his post, adding "hemi"..... Mr. Observant.

-Mindgame

Speaking as someone that's actually personally done many of these big inch small block chevys I would say "it depends!"

Big inches make power easier and more reliably than small inches and that's just a fact. As people here have brought up, the new GM LS7 is not smaller! This is not an accident. You can turn more rpm and you can make more tq or you can do both to make more power. Bigger engines though can make the power lower in rpm so they are usually reliable and that's why everyone does it or at least trys it!

Now the problems! As has already been mentioned here the big stroke cranks do not just fall in a SBC block! much thought and clearancing and only the right stuff can go in any particular SBC block. SBC blocks are also different and some have higher and some have lower water jackets in them among other differences. You can get cranks with smaller journals and smaller rods that will clear the cam and bores much easier but they are not ever cheaper.

If you want a truly big inch engine go with a real engine builder that has done this before. That way you are not stuck making all the mistakes that will happen to guys not experienced at it. I've done 450+ CID small blocks in the rocket blocks or iron eagles and even up to 447 in a stock 400 block and that is still running btw.

Not knocking anyone on here but I see much bad info on what clears and what doesn't and it all depends on the blocks in question and the builders competency. An LT1 block has higher water jackets for instance than an older 2pc rms SBC. You can run the eagle stuff out to 3.875 no problems and the 4.000 specialty cranks and rods in an LT1 without hitting water or the cam because I do it all the time and I mean without reduced base circle cams either but again you must know what you are doing (some slight rod machining).

At some point you are definitely on the diminishing returns side of the financial equation vs the power you are making though so that must always be kept in mind as shelf parts are much cheaper and easy to get.

racer.agreed.
but from my experience in which i just finished my 425,.050. over job,my eagle stuff didnt clear my cam,so i was forced to go to a small base circle,then as a result of running a small base circle,i was forced to run a different or longer lifter to offset the small base circle cam.
also.anyone thinking of building a stroker keep this in mind,bigger is better sure,but when it comes to running a 4 in storke on these stock blocks with a 6 in rod,it makes the ring grooves very tight and you dont get as well of a ring seal as you would like and since the pin is so high in the piston you could get some rocking of the piston especially if you over rev it,and that rocking up op could cause the piston to hit the head.just food for thought so you might want to think about sacraficing a few cubes and running the 3.875 stroke to help offset these troubles

but racer is right,aint none of these cranks fitting in a stock block with notch out the rail..sorry..
also look for a good casting,i got lucky and found a 511 casting,which is one of the better stock 40 blocks to build.some folk like to get a 2 bolt block cause theyre stronger down below and drill the 4 bolt mains ,which is good but costly ,just for the caps and then maching.if you find a 511 4 bolt block it will be good for most mild street engines.
also if your definetley lookng at a stroker with a stock block,look at the casting where the cam bore is,youll see a the bore and then its surrounded by a "boss" area,try to find a hole thats almost centered in that boss area.if its lower than the center line of the boss area move on.what happens there is when the block was made,that cam core shifted downwards and now your cam is a closer to the crank.in a stoke set up this isnt a problem,but when doing a stroker every inch counts and some blocks cant be used if this movent is off too much regardless of what you do.

racer,may i ask how what combo did you use to get 447 out of a stock block and was there any mods needed other than the orginal.

I am a believer that "bigger is better", but it won't do you much good to have big cubes if you don't have the heads, cam, valvetrain, etc. to support them. So, while this is a worthwhile topic to discuss, I don't want the newbies reading it to think that they have to worry about going to a lot of trouble/expense to eke out the last few cubic inches from their motor. Most people would get a lot more bang for the buck going with an "easy" combo like a 383, using readily available poarts, and putting the money into the rest of the components.

The World Products crate motor I posted the pic of uses a 4.25" bore and a 4.00" stroke for 454ci. The big bore is important for making hp as it unshrouds the valves relative to a longer stroke/smaller bore combo. A stock 350, if the core is carefully selected can be bored 60 over (for NA use) to 4.060". The upper limit on a 400 is 4.185". The Motown block that allows you to get these big bores costs ~$1,900. Not a huge amount in the contest buying the heads, valvetrain, etc. you need to support a big cube SB when compared to the costs of finding and rebuilding a 400 block. HP is not cheap.

I would use an aftermarket block for a big inch small block.

Rich

racer,may i ask how what combo did you use to get 447 out of a stock block and was there any mods needed other than the orginal.

4.155 bore and 4.125 stroke on the 447 regular SBC. They make pans and gaskets with the notches too.

You have to cut the rods at the shoulder on 3.875 and more stroke but it;s not much at 3.875 and still not the much at 4.000 and I do these all the time.

Also done many 4.185 bore by 4.000 stroke deals in World and Dart blocks and in the Worlds all you do is cut .125 off the right part of the Eagle rods! I use full normal base circle cams in these too.

MANY circle track deals come with 1.000 high pistons and they work great. Wiseco has a deal coming that will revolutionize how short people are running pistons soon.

I am a believer that "bigger is better", but it won't do you much good to have big cubes if you don't have the heads, cam, valvetrain, etc. to support them. So, while this is a worthwhile topic to discuss, I don't want the newbies reading it to think that they have to worry about going to a lot of trouble/expense to eke out the last few cubic inches from their motor. Most people would get a lot more bang for the buck going with an "easy" combo like a 383, using readily available poarts, and putting the money into the rest of the components.

The World Products crate motor I posted the pic of uses a 4.25" bore and a 4.00" stroke for 454ci. The big bore is important for making hp as it unshrouds the valves relative to a longer stroke/smaller bore combo. A stock 350, if the core is carefully selected can be bored 60 over (for NA use) to 4.060". The upper limit on a 400 is 4.185". The Motown block that allows you to get these big bores costs ~$1,900. Not a huge amount in the contest buying the heads, valvetrain, etc. you need to support a big cube SB when compared to the costs of finding and rebuilding a 400 block. HP is not cheap.

I would use an aftermarket block for a big inch small block.

Rich

I agree Rich for the most part and the World blocks already are clearanced for a 4.000 stroke crank and normal steel rods. The Eagles swing through just fine but need to be trimmed up at the cam. Again you have to know what you are doing here are you will be screwed when the rods hit the cam.

Also keep in mind that damn near every engine master small block making 700 hp on pump gas did not use extremely big bores as some here would lead you to believe. Heads can absolutely flow big (enough) numbers on smaller than maximum bores to take the said CIDs to a streetable rpm almost everytime. If you're going unlimited hp, rpm and engine size then max out the bores as well.

Instead of people being obsessed with stroke I see more that are obsessed with overly large bores and yet they often do not make the power that they thought. They think that just because they have a big bore that everything will work out for them. It won't if you don't do everything right to actually use those bores.

racer,4 1.25 stroke on a stocker..wow..wish i knew that,also what kinda rod length that thing run?i had to get the notch oil pan for my 427....

Guys FWIW.... base circle is dependant on lobe lift too.

If you have .440" lift at the valve it's basically a small base circle lobe compared to a .325" lobe lift cam like a HotCam.

Eagle has stroker clearanced rods that can help all of this as well.... but the smaller the rod journal and better quality of the rod they can squeeze more stroke in the motors.

Bret

Guys FWIW.... base circle is dependant on lobe lift too.

If you have .440" lift at the valve it's basically a small base circle lobe compared to a .325" lobe lift cam like a HotCam.

Eagle has stroker clearanced rods that can help all of this as well.... but the smaller the rod journal and better quality of the rod they can squeeze more stroke in the motors.

Bret

Right, and if you are doing .460-.480 lobes they can go no smaller really on the base circle as most cam grinders don't want a cam small than .875 even if its a steel cam core.

The reduced base circle deals are only going to pull the nose of the lobe back much if it's already a smaller lobe as Bret said.

I don't cut nearly as much off as Eagle does though on the rods as I just make it to where it doesn't enter the cam tunnel.

racer,4 1.25 stroke on a stocker..wow..wish i knew that,also what kinda rod length that thing run?i had to get the notch oil pan for my 427....

6 inch rods and in that case they were small journal chevrolet and a special carrillo stroker rod with the lower shoulders and it fit pretty tight!

Why buy a std. height cam tunnel block? I know it costs a little more to go with a raised cam but that's the way I've always looked at it. For a race block I wouldn't even consider anything I couldn't get a 55mm core in these days. They're the cat's meow IMO. For the street, at least you can step up to a BBC core and not have to worry about rod interference.

I've built three of these engines now and I wouldn't do it any other way. Yep, it costs a little more but I'd never lie to anyone and say that this stuff is cheap.

I do agree with Erik when he says to find someone experienced with this type of build. There are alot of issues that you will never have to deal with in a smaller engine.

-Mindgame

[/QUOTE]
also if your definetley lookng at a stroker with a stock block,look at the casting where the cam bore is,youll see a the bore and then its surrounded by a "boss" area,try to find a hole thats almost centered in that boss area.if its lower than the center line of the boss area move on.what happens there is when the block was made,that cam core shifted downwards and now your cam is a closer to the crank.in a stoke set up this isnt a problem,but when doing a stroker every inch counts and some blocks cant be used if this movent is off too much regardless of what you do.[/QUOTE]

No offense, but the cam location is referenced off the crank centerline. If the cam is closer to the crank then the block was machined out of tolerance.
If your machined holes are eccentric to the bosses then core shift occured or the block is just a poor casting. Lifter bores that are concentric to their bosses is usually a sign of a good block.

Dean

right stew,but my point was core shift is common,sometimes it doesnt effect the engine,but in a stroker case if your core shift lowered you cam closer to the crank then theres going to be that much less clearance between rods and lobes....

right stew,but my point was core shift is common,sometimes it doesnt effect the engine,but in a stroker case if your core shift lowered you cam closer to the crank then theres going to be that much less clearance between rods and lobes....

If it's that far out of tolerance (cam vs crank centerline) then you have bigger problems than rod to cam clearance. :eek:

-Mindgame

Why buy a std. height cam tunnel block? I know it costs a little more to go with a raised cam but that's the way I've always looked at it. For a race block I wouldn't even consider anything I couldn't get a 55mm core in these days. They're the cat's meow IMO. For the street, at least you can step up to a BBC core and not have to worry about rod interference.

I've built three of these engines now and I wouldn't do it any other way. Yep, it costs a little more but I'd never lie to anyone and say that this stuff is cheap.

I do agree with Erik when he says to find someone experienced with this type of build. There are alot of issues that you will never have to deal with in a smaller engine.

-Mindgame

The big key is to find someone who can machine the block correctly for all of this.... BBC cam tunnels or even getting the stock size bearing tunnel in the right spot is a big deal!

Bret

right stew,but my point was core shift is common,sometimes it doesnt effect the engine,but in a stroker case if your core shift lowered you cam closer to the crank then theres going to be that much less clearance between rods and lobes....


Core shift does not effect cam location relative to the crank.

Dean

The big key is to find someone who can machine the block correctly for all of this.... BBC cam tunnels or even getting the stock size bearing tunnel in the right spot is a big deal!

Bret

If you buy a Rocket block, it has the BBC cam bores. They're an option for the Iron Eagles.

-Mindgame

If you buy a Rocket block, it has the BBC cam bores. They're an option for the Iron Eagles.

-Mindgame

Yep I get them with the 50mm tunnels too sometimes and the bigger .904 lifters as well on something with more spring pressure.