Torque ? SB vs BB
#1
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Torque ? SB vs BB
Assume you build up an L46 Small Block to achieve 460ft/lbs Torque (which I think you could easily do considering its 380ft/lbs stock, right?)
And you compare it to a stock LS5 with 460ft/lbs of torque
shouldnt they be EQUALLY as fun to drive around town and stomp on it, etc.?
If not then why not? The SB would have more HP too, and rev higher - correct?
Somebody please convince me!!!
(I still cant decide which way to go!!!)
Thanks!
And you compare it to a stock LS5 with 460ft/lbs of torque
shouldnt they be EQUALLY as fun to drive around town and stomp on it, etc.?
If not then why not? The SB would have more HP too, and rev higher - correct?
Somebody please convince me!!!
(I still cant decide which way to go!!!)
Thanks!
#2
Re: Torque ? SB vs BB (mike229)
depending on your cam and other parts the small block will probably make the peak torque higher in the revs. Also you may build a peakier motor. A big block will have a broader torque cruve while still making the same amount of torque. Plus if you pick a big block you can tell people you have a BIG BLOCK. Big blocks are just plain cool!
Now if you want to flatten the torque curve of that small block you can either do a cookie cutter 383 or try and fit the longest rod in that engine with a 3.48" stock storke crank. It'll help, but the long arm of the 383 or a big block will make more torque than the short arm of the 350.
If this is going to be primarily a street engine, go for as much low to mid torque as you possibly can, and whatever you decide (big or small) will be more fun than a barrel-o-monkeys.
[Modified by 442olds, 4:13 AM 3/9/2004]
Now if you want to flatten the torque curve of that small block you can either do a cookie cutter 383 or try and fit the longest rod in that engine with a 3.48" stock storke crank. It'll help, but the long arm of the 383 or a big block will make more torque than the short arm of the 350.
If this is going to be primarily a street engine, go for as much low to mid torque as you possibly can, and whatever you decide (big or small) will be more fun than a barrel-o-monkeys.
[Modified by 442olds, 4:13 AM 3/9/2004]
#4
Senior Member since 1492
Re: Torque ? SB vs BB (mike229)
I've done many DD comparo's on BB's & SB's. Keep in mind that DD is not exact and shouldn't be treat as such. It is useful to get a general idea as to how components can work.
What I noticed, and what convinced me to go the BB route was the torque curve graph of the BB. It didn't seem to matter which cam I chose, I would consistently achieve TQ ratings on the BB starting out above 400ftlb! Depending on the cam chosen, peak TQ could be 550-600!(fly)
The SB may peak at 460ftlb, but it's graph looks more like a hill or mountain. The BB's TQ is flatter as 442olds described. Can you imagine 400ftlb at 2000rpm. :eek:
Even the lowly 1987 454 smog engine (from a Suburban) I used for my rebuild had 385ftlb of torque @ 2000rpm.
BB! :yesnod: :hurray:
[Modified by Jughead, 6:44 AM 3/9/2004]
What I noticed, and what convinced me to go the BB route was the torque curve graph of the BB. It didn't seem to matter which cam I chose, I would consistently achieve TQ ratings on the BB starting out above 400ftlb! Depending on the cam chosen, peak TQ could be 550-600!(fly)
The SB may peak at 460ftlb, but it's graph looks more like a hill or mountain. The BB's TQ is flatter as 442olds described. Can you imagine 400ftlb at 2000rpm. :eek:
Even the lowly 1987 454 smog engine (from a Suburban) I used for my rebuild had 385ftlb of torque @ 2000rpm.
BB! :yesnod: :hurray:
[Modified by Jughead, 6:44 AM 3/9/2004]
#5
Melting Slicks
Re: Torque ? SB vs BB (Jughead)
Displacement has a huge effect on the torque curve,and that's why the big block is such a hoot on a street engine. You can build a relatively mild BB that will smoke a SB. To try to equal a big block,(which I did) you have to build a hotter combination(cam,heads,stall).
To be honest I'm at the ragged edge of what most would concider streetable,and if I'd gone BB,I'd still have room to grow.Hind sight's 20/20. :banghead:
To be honest I'm at the ragged edge of what most would concider streetable,and if I'd gone BB,I'd still have room to grow.Hind sight's 20/20. :banghead:
#7
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Re: Torque ? SB vs BB (mike229)
Generally speaking a eng that makes it power/torq down low is a better street eng because you spend most of your time driving in the lower rpm range. To make a great street eng from a small block at a relatively cheap cost get a newer block that has a roller cam and then stroke it to 383 or larger, roller cams are great for making power over a larger rpm range and will rev to 6000 rpm's before valve float.
[Modified by Fevre, 9:57 AM 3/9/2004]
[Modified by Fevre, 9:57 AM 3/9/2004]
#8
Re: Torque ? SB vs BB (442olds)
....Plus if you pick a big block you can tell people you have a BIG BLOCK. Big blocks are just plain cool!
Also, I've read where the life of an engine is proportional to the size or diameter of the piston. BB's have bigger pistons and you wouldn't be placing as much strain to get equal torque & horsepower.
So for longevity, I would go Big Block. :cheers:
#10
Team Owner
Re: Torque ? SB vs BB (lotahp)
I think that if you have a 427 - 454 ci small block you have the best of both worlds.
You can exceed 600 foot pounds of TQ because of the large ci and you still have enough room under the hood that your not always cussing when you work on it.
Did you ever wonder why all the top C-5 race cars use 427 ci small blocks, when they could have just as easily install up to 500 ci big blocks? The advantage goes to the big small blocks not small big blocks.
You can exceed 600 foot pounds of TQ because of the large ci and you still have enough room under the hood that your not always cussing when you work on it.
Did you ever wonder why all the top C-5 race cars use 427 ci small blocks, when they could have just as easily install up to 500 ci big blocks? The advantage goes to the big small blocks not small big blocks.
#11
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Re: Torque ? SB vs BB (gkull)
I think that if you have a 427 - 454 ci small block you have the best of both worlds.
Why? YOu have a highly stress little motor with not enough room for heads that can really flow.
As for working on a big block I do not have a problem installing headers, changing plugs or anything else. Our engine bays are big enough.
The small block is just that A SMALL BLOCK. It is just trying to imitate the big guys. And we all don't want imitations. We want the real thing :lol: :lol:
Why? YOu have a highly stress little motor with not enough room for heads that can really flow.
As for working on a big block I do not have a problem installing headers, changing plugs or anything else. Our engine bays are big enough.
The small block is just that A SMALL BLOCK. It is just trying to imitate the big guys. And we all don't want imitations. We want the real thing :lol: :lol:
#12
Melting Slicks
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Re: Torque ? SB vs BB (mike229)
I built such a motor making about 440 lbs of torque and almost 500 horsepower out of my L46. Great engine! Personally, a better choice for me than the LS5. The LS5 has lots of torque, but no revvs - more of a truck engine in my book.
The LS5 is a much smoother engine than my radical small block was, but that was a price I was willing to pay. It is much easier to have great amounts of torque along with higher hp numbers with a big block than a small block. For me, the L88 was the best of both worlds: 500 pounds of torque and over 560 horse power. Those less inclined to take on a ultra high compression engine with long duration cam can still easily achieve a smooth 500 horse power level with at least the same torque using other BB combinations.
Chuck
The LS5 is a much smoother engine than my radical small block was, but that was a price I was willing to pay. It is much easier to have great amounts of torque along with higher hp numbers with a big block than a small block. For me, the L88 was the best of both worlds: 500 pounds of torque and over 560 horse power. Those less inclined to take on a ultra high compression engine with long duration cam can still easily achieve a smooth 500 horse power level with at least the same torque using other BB combinations.
Chuck