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Smallblock or bigblock, who's got overall power and versatility?

  • Bigblock motors

    Votes: 57 35.4%
  • Smallblock

    Votes: 72 44.7%
  • Not really a fair comparison

    Votes: 21 13.0%
  • Neither, I like to drive 4 banger cars with stickers

    Votes: 11 6.8%

  • Total voters
    161
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Discussion Starter #1
I've been thinking about big cube motors lately, and I'm starting to think that the smaller big block motors may be obsolete, maybe even the 454? Think about it, why would you build a street 396 motor when you could just as easily (and probably cheaper) build a 400 smallblock, or a smallblock stroker? With the smallblock, you're also saving a bunch of weight too. What are the advantages to having a bigblock motor these days if they really aren't getting you that much more cubic inches at the cost of bulk, weight and handling? I would venture to say a similarly built 434 stroker and a 454 would be very close on the strip... so what's the point of BB motors these days?

Only thing I can really think of is that the bigblock design may allow for more room on the heads and canted valves and such...

So cast your opinion and vote, lets make it stock bigblocks against large cube smallblocks and smallblock strokers.

K
 

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the only things that come to mind to me are,.....
  • torque is significantly higher in a bb
  • lower rpms in a bb to make the same torque as a sb.
  • in a strip only vehicle, the only drawback I see is the cost of building the bb vs the cost of building a sb.
  • and weight. but there's more than enough extra grunt in a bb to make up for that....:confused:

'sup KF?
 

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Discussion Starter #3
I guess what I'm saying is if you build a 434 and a 454 you've not going to see that much more low end torque on that 454, and you're more than 100 lbs heavier to start with, so your advantage is probably gone already. Cost of bigblock parts and a decent 454 crank will probably put you over the cost of a 434 stroker too... only reason I think the bigblocks put out lower RPM torque is BECAUSE of the cube advantage, which they seem to have recently lost...

sup nuttylarry?!

K:p
 

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i don't have one in front of me, but as best as i can recall, the torque curve on a bb is almost flat compared to a sb. I do not even have a clue what a stroked sb torque curve would look like.... but what i think i'm trying to say is that the bb is making as much torque at say 2000 rpms, as a sb that has to rev up to 3500+ to hit that mark. ?.?. less rpm = less wear and tear on parts.

but.

if it was me, and it was a strip only car, i'd stick as much motor in it as i could.

and NOTHING sounds like a bb with open pipes. (insert imagined deep grumble here X)
a sb just sounds like a sb.
 

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The Smell of Nitro in the morn
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Neither, I like to drive 4 banger cars with stickers. :thumbup:

Why not compare a 502 SB and a 502 BB.
 

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Pure American Muscle
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Look at it this way a BB has bigger parts and weighs more. SO the rotating mass of a BB haveing much bigger pistons and connecting parts therefore more force is needed to turn those parts. In any engine over coming friction is a problem BB do this job by brute force and their parts pay for it. Sure they have more TQ right from the start thats what cubes do to an engine but the engine its self needs to get that mass turning before it can use it. Thats where a small block comes in with any type of stroker small block that ups the cube size of an engine you do something that is perfect. You take the same fricton in a stock say a 350 but you increase stroke making a 383 what you have just done is made an engine that needs the same amout of force to overcome friction as the 350 did but with alot more bang. A small block can get its RPMs up higher right at the start since there is less mass rotating the parts. Wear in a SB while having to make higher RMPs is a lighter rotating mass therfore wear is = to that of the havier more wear BB's and besides BB's take the RPMs through the roof 7000 on up isen't crazy at all.

If you ask me a BB is great to have and alot of fun to play with but i'd keep them for use as drag cars or some really nice street machines with the BIG BB
The small blocks are simpely easier to deal with parts cost less and you can for any normal use get the same bang as a BB for much less.

I suppose that what it comes down to
With a BB the skys the limit but once you get up in the clouds a ways running it on the street isent much of a thought.
A SB while maybe only making it to the clouds can show off that power to everyone in town.
I don't know that's just my 2 cents
 

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It may be true that the smaller bb's are obsolete such as the 396/402 how ever when you start getting to the larger displacements such as 427 of bigger you end up spending as much if not more building a small block which very likely won't have the durability of a less stressed bb of equal size. Not only this but the bbc has a better flowing head design in the bb and fantastic oiling system
So I would say no bb's still have their place and will into the foreseeable future.
 

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It's symantecs in most cases. It depends on what blocks you use in comparing same cube small block vs same cube big block. (especially when you start getting large displacements) If you compare equal stroke and bore small and big block engines, the only differences will be the variances in how they breathe (cam and heads). From what I have heard and read, big heads for big inch small blocks are not available. However there are several choices out there for big blocks.


I guess from my point of view if your looking for something around 400-454 cubes, you can certainly go small block but, I have known several people to build 454-468 big blocks that made a ton of power on a very small budget. I don't think building a dependable high output big inch small block will be cheap either.

I was under the impression that stroke and bore combos affected torque and HP and the size of the block wouldn't matter (unless it impedes the stroke).

HP costs money no matter wether it's a small or big block. The more exotic...the more expensive.

I think Robinson Robin hit it on the head.
 

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killerformula said:
I guess what I'm saying is if you build a 434 and a 454 you've not going to see that much more low end torque on that 454, and you're more than 100 lbs heavier to start with, so your advantage is probably gone already. Cost of bigblock parts and a decent 454 crank will probably put you over the cost of a 434 stroker too... only reason I think the bigblocks put out lower RPM torque is BECAUSE of the cube advantage, which they seem to have recently lost...

sup nuttylarry?!

K:p
You can't just look at the cubes. You have to take into account the bigger valves used in the big blocks. The head design. The longer rods which increase torque. The bigger which bore increases everything. You are comparing apples to oranges.

I wouldn't build a 396. I think they are kind of lame. A 427 or a 454 would be nice. I am sure if I were to build one, I would end up with one of the stroker big blocks. Anything above 500 cubes is "the sh*t".

A downside to big blocks is that the extra weight seriously impedes handling. The extra weight on the front end is a big difference. Think about weight transfer etc.
 

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I agree with the others....

You can bore and stroke a sbc to 454 and your pushing it to some degree, to its limits and your gonna spend big bucks on the rotating assembly/ setup to make it strong.

The 454 is already 454ci and its bone stock...if you wanna stop at 454ci then its your call but the just imagine where the 454 can take you cubic inch wise...someone made the point about power output...when can you take a bone stock 350 throw a cam/headers/intake/carb on it and make close to 500hp and over 500 lbfttq....my brother did one.....weiand intake...holley 750...lunati cam....w/t headers made 470 hp and 517 tq albeit at the crank but that was a nice street strip engine.

Down side...bbc engines are getting hard to find..at least in this area.

Another point previously mentioned, you can't IMO substitute the sound or feel of a big block....its addictive.

Good luck
 

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Discussion Starter #11
lluciano77 said:
You can't just look at the cubes. You have to take into account the bigger valves used in the big blocks. The head design. The longer rods which increase torque. The bigger which bore increases everything. You are comparing apples to oranges.

I wouldn't build a 396. I think they are kind of lame. A 427 or a 454 would be nice. I am sure if I were to build one, I would end up with one of the stroker big blocks. Anything above 500 cubes is "the sh*t".

A downside to big blocks is that the extra weight seriously impedes handling. The extra weight on the front end is a big difference. Think about weight transfer etc.
That's what I figured somebody would EVENTUALLY say!

right, with the BB you've got bigger bores which breathe better (in performance terms) and more head area in which to put valves and influence flow. So in a similarly built car with similarly built engines (say 454 big and a 454 small) you still think the bigblock would take the flag? Got a bit more mass to get off the line... weight transfer of the car isn't as good... My bet would be the smallblock.

I like these threads that influence theoretical discussion-

K:thumbup:
 

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What about identical bore and strokes? With aluminum heads on both? With similar cams?
 

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Miket said:
What about identical bore and strokes? With aluminum heads on both? With similar cams?
with identical cubes. the BBC would still out perform simply because the BBC has better flowing heads.
You simply cannot have the same cams.
 

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Discussion Starter #14
aluminum heads and cams would be assumed, of course, in teh phrase "similarly built."

As far as bore and stroke, no. smallblocks can only go about 60 or a little more past (aftermarkets maybe .120?) 4.125

Stroke woudl be longer on the smallblock, by definition-

K

badazz81z28 said:
with identical cubes. the BBC would still out perform simply because the BBC has better flowing heads.
You simply cannot have the same cams.
How can you say the big block would have "better flowing heads" if we dont know which they are? Do you mean total flow, or airflow velocity too? Because if they're giving up the velocity for the flow, the smallblock will have more low end torque, and jump the big even more off the line.

K
 

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I think it depends on the size you test....because aftermarket small blocks are capable of producing similar strokes and bores... IE454-472....

I have to think cam specs would be close so the next item would be flow numbers of each heads used along with intake runners and compression ratios....correct?
 

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we need to stop beating the dead horse, We all know the bigger motor is going to produce more power
SB and BB are different motors that have different powerbands. Yes SB can make lots of power. nobody is arguing that.
The bigger the motor is the more reliable power it can produce. A 500 hp SBC is not going to be as reliable or streetable as a 500hp BBC
A basically stock 454 can make 500hp easy. You would have to work on a SBC
The BBC is simply the power monster
 

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I've had both SBC and BB's and I have to say I'll probably never own another SB. When it comes right down to it if you built a nice SB 454 and an equivalent BB 454 who knows who would win in a race. Kind of depends on what type of car you put it in also. I don't have a lot of theory to back it up but BB's just seem to have a larger flatter torque curve and that's what counts when you're trying to get a 3500lb car moving. Now if I had a 2000 lb drag car I would seriously consider a SBC and wind it to the moon.

Right now I have a 396 in a chevelle. I would have got a 454 but I got a deal on the 396 I couldn'g pass up. I already have dreams of buying/building a 500+ cubic inch beast. My ideal engine without going too overboard would be a Merlin 540.

That's another point to look at is cubic inch potential for each. It's not uncommon to see or read about 540+ BB's but what's the biggest small block you can build using an aftermarket block. Probably not a lot larger than a 454 which would cost a bunch of dough in the process.

Partly comes down to personal preference and to each his own...let the drag strip sort them out!
 

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Another thing to consider is the cylinder walls on a SBC 454 are a whole lot thinner than on a BBC 454.

The BBC is going to last longer and be stronger than the SBC 454. With the BBC 454 you can have the rings below the piston pins.
 

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Discussion Starter #19
badazz81z28 said:
we need to stop beating the dead horse, We all know the bigger motor is going to produce more power
SB and BB are different motors that have different powerbands. Yes SB can make lots of power. nobody is arguing that.
The bigger the motor is the more reliable power it can produce. A 500 hp SBC is not going to be as reliable or streetable as a 500hp BBC
A basically stock 454 can make 500hp easy. You would have to work on a SBC
The BBC is simply the power monster
:rolleyes: :rolleyes: :rolleyes:

there is NO "size" difference between a 454 small and big block... that's what the whole freaking thread is about dude.

K
 

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killerformula said:
:rolleyes: :rolleyes: :rolleyes:

there is NO "size" difference between a 454 small and big block... that's what the whole freaking thread is about dude.

K
geez man even though the displacement is the same they are still two different motors! If you had the same displacement, heads cams etc. it would be the same motor right? Than there would be no comparison. Now since we are talking BB and SB the BB has bigger heads, More flow. Able to handle more cam. The BB is going to make more power.
What if I said I bored and stroked out a honda motor to a 350ci would it be the same as a SB 350?
Man only if GM thought of making Big cube small blocks instead of the BBC( They did it for a reason)
 
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