Now, this may be a dumb question to many of you, but could someone explain to me the difference between a 'big block' and a 'small block'. What are the advantages and disadvantages of each? I just bought a K5 with a small block 350, bored out .30 over.
Just curious.
Thanks
Brent san diego, CA
no, you bought a 350 bored out 0.030"
' .30 ' would put you into the water jackets
a small block is a first gen chevy V8 displacing
262,265,267,283,302,305,307,327,350 or 400 CI. the blocks can handle a maximum bore of 4.125" and a maximum stroke of 3.75" (b/s of a 400ci).the second gen v8 (LT1/LT5) and 3rd Gen V8's (LS1,LS6) have displacements of 5.7liters and are not compatible with the first gen V8 small block.
a big block chevy is a v8 displacing 366,396,402,427,454,502 or 572 ci.
the small blocks advantage is decent power in a relatively light package.
the big block's advantage is simply HP and Torque. the larger big block simply has more room for stronger components and better ports.
HTH, Bret
the short simple answer is this.
A big block produces more HP and torque and also consumes more gas. A big block generates more torque and horse power in the lower rpm range.
A small block makes reasonable HP and less torque , and it comsumes less gas in doing so. A small block makes its horse power and torque in the upper rpm range.
Most "tow" vehicles run a big block due to its ability to generate a lot of torque in the lower rpm range. THis makes a big block the better tool for moving heaving loads, the trade-off is that it comsues a large amout of fuel to do so.
the generally accepted pro for the big block is its ability to move heavy loads and generate power at low rpms. The con is the fuel milage.
The generally accepted pro for the small block is the better fuel milage and the ablitly to make power in the upper rpm ranges. The con is that its less powerful..
Big Block(Rat)=Big power, Big money, Big weight Small Block(Mouse)=Fair power, little money, decent weight If you want to floor it and have your nutz crawl up inside you from fear, Get a Rat! If you can afford it. If you want to be able to pass at least a couple gas stations, on don't want retracted testicles, Get a Mouse. I don't need my testicles anymore and my mouse is gettin pretty sick so I cant pass any stations anyway. Plus I can get my hands on a couple turn key
454s for 5-8 hundred each that don't even need freshening up.Just call me Rat Boy!!!
Never mind...Keep calling me Shades...
What that was all about is...If you need BIG power, have money to spare, and don't mind less than ideal MPG, Get a Rat Otherwise, keep your mouse! More than adequate power can be had from a Mouse for half or less than half of the cost of rebuilding a stock Rat. Plus, you could get a truck load of Mouses from almost any salvage yard. Rats are VERY scarce and one would cost the same as the truck load of Mouses...
I want one. Lemme know where to be and when.
Doc
The primary difference between a small-block and a big-block is weight and cubic inch displacement capability. I am presently building a stroked small block displacing 383cid producing over 425 hp and 500 ft. lbs. of torque below 5,000 rpm. Those Rats may rule the sewers but my Mouse will rule the woods.
-- Mad Dog
79 Scottsdale 4x4
Is the 572 gas or diesel? I think my future chevelle is calling for it...
-The Lonely Grease Monkey
1985' K5 305CUI TH700R4 NP208 KJ's successor"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
the ZZ572 is a 620 HP (pump gas version) or 720HP (race gas) gasoline engine.
-Bret
It'd be nice if some company made a swap kit to put a VW W16 engine under the hood, 700+ KW.
rhys
a big block chevy is a v8 displacing 366,396,402,427,454,502 or 572
Those are/ were availiable factory or crate. But If you're gonna spend money, look at stroking a good 'ol 454, any one'll do. You get 'em out to
496 or 525, with the long stroke of those you'll see some retarded torque numbers and down low too. Seems like everybody and their dog gets or wants a 383 stroker when their 350 bites it, but be different stroke a BBC.
I just want to go places and when people ask "what chew got?" "A 572, .030 over, super charger, turbo, 300hp nos, posi rear, munchi
4sp (do they make a good 6sp?). A good 0-60 run will transport you back to the start line, so you can see your car take off the line again (and again [and again {and agian}])" "ya I got a 350....and stuff"But I'd settle for a 454 for my K5 (my chevelle MUST have a larger engine, period...)
-The Lonely Grease Monkey
1985' K5 305CUI TH700R4 NP208 KJ's successor"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
a muncie 4 speed would last about 5 seconds behind a 600HP motor, I think your trans options would be more towards a built TH400 or a Lenko... the ZZ572's torque even far exceeds the mighty NV4500's 460 ft/lbs rating.
-Bret
ok... fine... I'll reiterate, with 750 ft/lbs of torque, you're either going to have to use an auto or a Lenco sequential shift... nothing else that would even romotely fit into a chevelle will hold up.
-Bret
For a Chevelle? Thats a small coupe style car innit?
try googling for what GM Australia uses in their manual HSVs, a T56 six-speed manual gearbox.
at least 575 lb/ft of torque in the 2002 HSV coupe, would it stand up to
750?rhys
Hmm... more on the T56.
It's a Borg Warner box and is able to take the V12 with 645 lb/ft of torque.
most sports cars tend to get 0-100 KM/H in under 8 seconds, but thats only
62 MPH.Nice car.
rhys
depends on the year, they were never small... pre '66 I'd call them a large car, and a midsize from 66 on.
-Bret
To Brett: You were talking about putting it in my truck. Just wanted to remind you what we were talking of, not saying you are wrong at all. I guess I will have to go for a smaller engine, I really, really, really, really, love manuals....
To rnf/Brett: It's a G-Body car. 16' long if I remember, just as wide as a K5 by the "looks" of it. They fit the 502 (Until this thread I had never heard of the
572)~KJ~
G-Body? Means absolutely nothing to me. :)
Doing a bit of google-work it seems about a 70's Holden Monaro-ish size, should take a T56 with a bit of work. you may have to detune the 572 to 645 ft/lb of torque. But the T56 will fit a modded Jaguar E-type, should be small enough to go in a Chevelle, and strong enough to take a BBlock.
rhys
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