Big Block vs. Small Block

Now now, don't everyone get their knickers in a knot, they both have their good points, but sure you could build the same amount of power in a small block as a bigblock, but it wouldn't drive as nice and you could build the big block to produce even more power with the same amount of driveability. IMO neither is BETTER than the other. (Which I guess means in general) They have their own applications at which they excel.

Smalls are smaller, make less torque so need to run higher rpm to get big power, are lighter and possibly more fuel efficient, so more suitable to circuit racing where laps between refuelling, corning ability and sustained high speeds are important.

Drag racing is more suited to the big block because you can get an overall better power to weight ratio, it doesn't matter how much fuel it drinks, and it doesn't matter if is hardly turns.
 
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blue66tang said:
Same hear, everybody thinks i have a big block in my car. Nobody can believe its just a little 289 with 12.5 compression making that sound. Personaly i dont realy like the sound of my car. This summer when i will finaly be able to do a little tuning on it, if it doesnt sound any better i think i might, put some flowmasters on it, or take the tail pipes off, and see if it sounds any better.
Gosh if i could post a vid, i would let you guys hear it.

Yeah, mine has heavy old TRW 12.7:1s in it, but with the bigger chamber of the '69 heads, I'm guessing it's about a point off. Mine sounds GREAT!! but that's with open headers. My buddy describes the sound of a properly tuned Ford motor as kernaling (sp?). I've heard several motors that are tuned right with this sound, when mine started making the sound and he said something about it, made me pretty proud. It sorta sounds like my drum roll, I'm not very good at it and my left hand is slower than the right, so the right catches up to the left and they're hitting at the same time, then it passes the left and its back to the way its supposed to sound, then back to catching up. That's the only way I can describe the sound.
 
Well, small blocks are still around in performance cars. I think thats the best argument in their favor...

Every performance V8 (form Ford to Mopar to Ferrari to Aston Martin) is built in a mid-ranged, small-block esqe displacement now. There is a reason for that. I'll leave it at that.
 
Sad,

What is small block displacement considered to be? Chevy made a 400 SB and a 402 BB (heck they made a 348 BB so the 350 argument goes out the window). Ford made a 352 BB (well, before that there was the 332 BB). Is the 5.0 (302) the limit for a small block displacement? Some of those engines you mention are well over the t.o displacement due to more than 8 cylinders. You may have 3" bores, but if you have 12 cylinders, the size is longer than a BB.
 
I think the big reason for going away from the BB motors is in many cases, they're not needed due to the diesel motors that are out there. Now a 7.3 is a BB really. A V10 motor is 6.8, but the cylinders are the same size as the 5.4, is the 5.4 a SB?
 
Both motors have plusses and minuses...just don't knock what I have. I have driven both and I am a dedicated believer of big block power.

In answer to the original question... any sort of straight through exhaust (glasspack) with a little bit of tail pipe for tone will give you a nice throaty rumble. In the 80s when my 67 had a 289, I had sidepipes and people always thought that it was something a lot bigger.
 
Having driven both, I like them both... but see my screen name... :D
Seriously though the major difference between a big block and a small block is how the power is developed. Look take a big block, like a 390 and a small block say 351w - and say they both generate 400 ft/lbs torque. The 390 get that figure at around 3200- 3400 rpm - the 351 on the other hand will not reach that figure until 4800-5000 rpm. This is the principle reason I like the Big Blocks... nice, streetable, WHAM! in the seat that I don't have to rev the engine high to get when you let the clutch fly. You guys should try it sometime - how many small block cars get stress cracks from the body twisting? :D
 
Big-block - high weight straight line.
Small-block - high revving twisties.

What you choose is what you like. If I were at the 1/4 all the time, It would be big block for sure. I personally like Autocross and Open Track so I'm building an aluminum head roller block.

My inspiration... 500HP 289
http://www.cobraautomotive.com/race_movies.htm
Check out the last two movies at Watgen's Glen. Also keep an eye on the tach effortlessly spinning to +8k. It's a beautiful thing.
 
66P51GT said:
Big-block - high weight straight line.
Small-block - high revving twisties.

What you choose is what you like. If I were at the 1/4 all the time, It would be big block for sure. I personally like Autocross and Open Track so I'm building an aluminum head roller block.

My inspiration... 500HP 289
http://www.cobraautomotive.com/race_movies.htm
Check out the last two movies at Watgen's Glen. Also keep an eye on the tach effortlessly spinning to +8k. It's a beautiful thing.

Hey now... a big block car will turn.... just give it more gas when it starts to plow... I GUARANTEE that it will rotate though the corner :rlaugh: Just having fun... The big block vs small block thing is almost as much fun as Ford vs Brand X :nice:
 
The difference between a stock dressed out 351W and a 427FE is about 120#. The FE has a steel crank and an aluminum intake. I'd think a 390FE with a cast crank, cast iron intake would probably be about the same as the block is a little less beefy. So throw a set of aluminum heads and intake on the 390 and your getting close to the 351W weight. Granted, you can do the same to the 351W, but the weight of the parts is less. You can stroke the 351 to 392 and the 390 to 454 for about the same cost.
 
67GTA-FB429 said:
sure. small blocks are for people who want to throw lots of daddy's money at an engine to get to the starting point of a big block.


Daddy's money? Let's take your motor for instance. 429 T-Jet/ 372 hp/ 490 ft lbs. Then, you take my motor. 351W/ 460 hp/ 495 ft lbs. Dont get me wrong, but to me it looks like a smaller motor (not to mention lighter) with more horsepower and more torque.

And if I remember correctly the 429 T-Jet stock should produce 360 hp. You are only 12 hp on that? That tells me you must have changed either the exhaust or maybe the intake? just a secret between you and me, your not going to a win a race that way.

So if you think I spent "Daddy's money" it looks like I spent "that wisely huh? :banana:
 
TRICKFastback said:
And if I remember correctly the 429 T-Jet stock should produce 360 hp. You are only 12 hp on that? That tells me you must have changed either the exhaust or maybe the intake? just a secret between you and me, your not going to a win a race that way.
That'd be gross HP there chief... His sig specifically states rear wheel HP, which means he's had it ACTUALLY dynoed, not put into a dyno simulator. If you think a stock Thunderjet really made 360HP to the rear wheels I got this SWEET piece of land to sell ya. :p I also remember reading some of his posts when I was gonna build a big block (still would if I could afford it, no replacement for displacement), and remember him saying his setup was pretty tame and still made those numbers.
 
nosaj122081 said:
That'd be gross HP there chief... His sig specifically states rear wheel HP, which means he's had it ACTUALLY dynoed, not put into a dyno simulator. If you think a stock Thunderjet really made 360HP to the rear wheels I got this SWEET piece of land to sell ya. :p I also remember reading some of his posts when I was gonna build a big block (still would if I could afford it, no replacement for displacement), and remember him saying his setup was pretty tame and still made those numbers.

yep REAR WHEEL HORSEPOWER and REAR WHEEL TORQUE. Most of my mods in the valve train.
 
66P51GT said:
Big-block - high weight straight line.
Small-block - high revving twisties.

What you choose is what you like. If I were at the 1/4 all the time, It would be big block for sure. I personally like Autocross and Open Track so I'm building an aluminum head roller block.

My inspiration... 500HP 289
http://www.cobraautomotive.com/race_movies.htm
Check out the last two movies at Watgen's Glen. Also keep an eye on the tach effortlessly spinning to +8k. It's a beautiful thing.

I know that movie. I have it downloaded, it is awesome. How much does that 500hp 289 cost again? And I can turn 6500+ in my 429...that sounds pretty cool too, at least that is what the neighbors say since I can't hear anyting inside the car except the screaming engine. :D
 
66P51GT said:
Big-block - high weight straight line.
Small-block - high revving twisties.

What you choose is what you like. If I were at the 1/4 all the time, It would be big block for sure. I personally like Autocross and Open Track so I'm building an aluminum head roller block.

My inspiration... 500HP 289
http://www.cobraautomotive.com/race_movies.htm
Check out the last two movies at Watgen's Glen. Also keep an eye on the tach effortlessly spinning to +8k. It's a beautiful thing.
well said. :flag:
 
I've owned a 390 that would pull 7k in a 66 gt fairlane

I own a 331 that pulls 7000 in a 67 fastback.

I never dyno'd the 390, but the 331 in the car makes 346 hp @ the wheels.....I prefer the 331 motor it rev's better....it comes on cam strong and by the time it's making torque the cars moving and holds traction better.

the 331 cost a lot more, but weight is a lot less,more room to change the plugs...took lifting the motor about an inch off of the mounts for the fairlane.
less heat issues.....more airflow around the motor

I hated working on the 390 rocker arm system is crap,can't chage the intake with out pulling the pushrods...wtf...and the stupid h20 pump short hose that cant be replaced with out pulling the pump



the plus side of the big block the geewiz factor
and it won't split if you make over 500 hp



JB
 
All these arguements against big blocks due to weight/bad handling are not very relevant.

A big block with aluminum intake/heads will weigh a little over 100lbs more than a small block. It's not like you're throwing the titanic on the front of your car by running a big block. You can overcome the weight with suspension mods and bracing, setting the engine further back behind the front axle (maybe not in a Stang), not to mention the traction benifits of modern tires.

I'm planning on doing a Cobra kit in the near future to both drag and autocross, and I am having no second thoughts about my plan to go with a big block.

Not knocking small blocks (look at my car), but other than fuel efficiency and cost, I just don't see the advantage of not going big block.

Just my opinion. :)
 
67GTA-FB429 said:
I know that movie. I have it downloaded, it is awesome. How much does that 500hp 289 cost again?
Way more than I can afford. Your point is well taken. I've heard that car has over $100k into it. It definitely takes serious $$$ to play at the top of the vintage racing circuit. However, it doesn't take nearly as much money to have just as much fun.
 
The big block has more power potential hands down. The big blocks are also better suited to handle massive amounts of power. Anything that you can do on a small block can be done to a big block, just depends on how much money you have. As for sound, there are so many different configurations out there you can possibly do. It is just finding the right combo to your taste.
Kevin