Battle: small block vs big block

[Troy]

If the original question were changed to include handling it becomes a much broader field of discussion for sure.  I wonder if the difference in weight between a stock 440 and stock 340 would make an enormous handling change. 

I don't know about enormous but I'd be comfortable with "very noticeable". I have been reasonably surprised at the performance of the Challenger (1st E-body I've owned with a big block) but it's by no means "tossable" on the back roads that I like to drive on. As I stated earlier, the 340 cars got heavier suspension and would pretty much run away from similarly equipped 383 models through curves. For what it's worth, the door sticker on my 340 Challenger says 3,260 pounds.

Troy

[chargd72]

If the original question were changed to include handling it becomes a much broader field of discussion for sure.  I wonder if the difference in weight between a stock 440 and stock 340 would make an enormous handling change. 

I have heard multiple claims that you can feel a difference in the handling.  To what extent, I'm not sure.  Also,  I wonder how much the weight difference would be noticed in the brakes.  That difference in weight up front where it counts could really have an effect on how much later you can brake before a turn. 

[Ghoste]

Do you think those differences would be more noticed in a smaller car like a Dart?  Or shorter wheelbase cars such as the Cuda?

[Rayzor]

Since my 68 was a original slant six car, I feel I can add to the weight vs, handling.  Im not sure how much more the 440 I swapped in weighs but I would guess over two hundred pounds then the slant. The steering is now alot heavier, the fronts break loose sooner and the car wallows in the corners alot more. I have added better sway control and torsion bars but have yet to come back to the light handling. But on that note I can steer now with the back tires and the torque!  

[SRT-440]

I noticed a difference when I went from a 318 to a 440 in my '71 Dart...with the 318 it handled better and just rode better (if that makes any sense). Now, it's a bit nose heavy and clumsy feeling...the torque is great but makes that car pretty useless when it comes to hooking up. My 92 year old grandmother in her '79 Lebaron could prolly take me from stop light to stop light..LOL. It needs to be mini tubed with some drag radials...even tho spinning the tires at almost any speed is fun it makes for a slow racer.

I'd be willing to bet a built 340 or 360 or even *gasp* a 383 would allow the car to perform better over all and not in just the torque department. 300hp that gets put to the ground will always beat 400+hp that can't get to the ground. 

[chargd72]

Great info guys!  Fifth gear did a shootout between the Dukes Charger vs Starsky & Hutch Torino.  It was on a track with plenty of turns, straight aways and chicanes to test all areas of performance.  I think we all know the winner of that matchup    A test like that between the SB and a BB would be ideal to see where each has its place.

[SRT-440]

That chic that did the Fifth gear episode was prolly the lamest driver they could have gotten...when she said she couldn't get the chargers rear to break loose around the corners I knew she shouldn't be behind the wheel. Next time they should make sure the driver can see over the steering wheel before they let them test there cars. 

But an all around sb vs bb shoot-out would be great...both being in "street trim" no slicks and built the same..either both "stock" or both "modded"..no stock vs modified. 

[Ghoste]

It would be fun.  Myabe we need to start a write in lobby campaign to get them to try it.

[chargd72]

That chic that did the Fifth gear episode was prolly the lamest driver they could have gotten...when she said she couldn't get the chargers rear to break loose around the corners I knew she shouldn't be behind the wheel. Next time they should make sure the driver can see over the steering wheel before they let them test there cars. 

But an all around sb vs bb shoot-out would be great...both being in "street trim" no slicks and built the same..either both "stock" or both "modded"..no stock vs modified. 

Yeah, I was hoping she wasn't the driver for the REAL test since she was leisurely talking to the camera as she putted around the track, but who knows. 

Ghoste, I think you're on to something...   

[Mike DC]

I've wondered what a 2nd-gen Charger would feel like if you ran one of those GM/Rover aluminum V8s in it.  Rover got them up near 300 cubic inches and they only weigh about 320 pounds.  Combine that with a lightweight tranny like a powerglide or something, use some aftermarket suspension parts, convert it to R/P steering(which would be better suited to the car when the front end is lightened) . . . you're probably looking at almost 500 pounds lost from the front end.  And that's before you even get into classic lightening mods like changing the body panels or stripping down the luxuries.

[morepower]

Deffinately big block. You have more future potential power. and its just not the same when someone asks you whats in that thing...440 sounds waaaay better than 340

[Ghoste]

I knew a guy once that had a well warmed 340 in a late 60's B-body and he had one of those Holley 500cfm two barrels on it.  He told everyone it was a 318 two barrel with headers and surprised the hell out of a lot of brand X cars with it.  I know he'd insist that the fun factor in that alone was worth having the smallblock. 

[Cooter]

Deffinately big block. You have more future potential power. and its just not the same when someone asks you whats in that thing...440 sounds waaaay better than 340

Amen Brother...This is why most 440-500 C.I. A Bodies round here usually show you the mufflers when they leave, as they have TIRE under them...If I wanted to road race a vehicle/carve canyons/etc. I'd have bought my IROC back..Loved the car, handled like a dream, but it just didn't have it in the stop light to stop light challenges...Nobody I know of here, "Road Races" and if they do, they usually end up like the post a while back with those two racing up that mountain with the people walking along side the road. Most everybody here does the Point a to point B when referring to performance and Small block  VS Big Block...Big Blocks rule this area.(Everything else being equal). I got a Slant 6 3-speed Dart sedan, it handled like sh*t when it had the slant 6 and once the Big Block was in it it STILL handled like Pure D sh*t...

[Cooter]

I know he'd insist that the fun factor in that alone was worth having the smallblock.  

As stated before, I know ALOT of guys that will spend ungodly amounts of money for that sole reason too...

[morepower]

Deffinately big block. You have more future potential power. and its just not the same when someone asks you whats in that thing...440 sounds waaaay better than 340

Amen Brother...This is why most 440-500 C.I. A Bodies round here usually show you the mufflers when they leave, as they have TIRE under them...If I wanted to road race a vehicle/carve canyons/etc. I'd have bought my IROC back..Loved the car, handled like a dream, but it just didn't have it in the stop light ot stop light challenges...Nobody I know of here, "Road Races" and if they do, they usually end up like the post a while back with those two racing up that mounhtain with the people walking along side the road. Most everybody here does the Point a to point B when referring to performance and Small block  VS Big Block...Big Blocks rule this area.(Everything else being equal). I got a Slant 6 3-speed Dart sedan, it handled like sh*t when it had the slant 6 and once the Big Block was in it it STILL handled like Pure D sh*t...

haha a man of my own blood. I have a 89 camaro I drive daily that handles well so im point A to B in straight line thinking with the charger also...NOTHING sounds better than a big block MOPAR driving down the block, or idleing around in traffic...I get chills thinking about mine runnning again.....

[68corazonetR/T]

  This very interesting to me because I just sold a complete engine and transmission (1974 Labaron 440) to a guy who I believe isn't going to do much to it other than dress it up and make it look good, drop it into a challenger and hope for the best. He might get lucky and I hope he does get some years out it.  My intent was to rebuild it and to raise the compression ratio and put in my Coronet but when I really got looking at all the facts it was going to take a lot to make it anything else otherthan a boat anchor and this includes beefing up the suspension to handle the weight. If your going to go from small to big you must add the torsion bars and springs to get right. Turning up the smaller torsion bars in my books is a big no no. I like what Flying low said because I did the exact same thing with mine with its 318....ran it with the car stripped of everything over to a buddies for resto work and man what a noticeable difference. I like the small blocks for this reason.... the cars handle real nice with them. I imagine it would be stiff as hell but imagine how well a SB will handle with BB suspension. In my case I think I made the right choice to stick with the steel crank original 1968 318 and maybe tweak it up a bit. But in the end A car built right and a 440 built right with a 5 speed would make me drool. The torque really is what gets those wheels turning.

[Cooter]

"Beefing up the suspension to "Handle" the weight"...BS myth...I has a 505" stroker sittin' on Slant 6 front suspension right now, and I had to lower it to get the ride height where I wanted it..Sure, it's not gonna take a curve at 120 MPH, but then again, not many stock suspensioned R/T cars will either...And you are correct, no, Mopars are not as easy top convert as say Chevy. "Why certainly, you can take out that 150 HP 305 and BOLT IN your 650 HP, 468 BB Chevy right to that T 350 trans"...No, if you prefer things this easy, then maybe brand X is your speed.


"imagine how well a SB will handle with BB suspension." Ok, now imagine how a BB car will handle with aftermarket RACING suspension, built for this type thing?

This discussion is NOT about handling...It's about HP to weight and whether there actually is a replacement for displacement..

[68corazonetR/T]

  Look up because it was mentioned and so I'm putting my 2 cents in....You can crank your slant six torsion bars up or down as much as you like with a big block but look into this before you call it a mith... There are reasons to why things are the way they are.... torsional strength....don't go too far cause she's gonna break or deform... spring rate and range are important. I agree with you about your theory though....you start out bigger you can end up bigger and so there is no replacement...
  To the guy who started this discussion.....
My higher compression 318 vs the 74 low compression 440 and bang for your buck, I can put a little money into this engine and maybe get a little closer to the Hp of the 440. I think the same amount of money in the 440 wouldn't go far and I would have to spend money on the suspension if I wanted it to feel right and keep it on the road.....for the time being this is why I opted to get rid of the 440. For the price and when the time is right I might buy a crate engine and save myself the hassle

[Troy]

Who said it wasn't about handling? Lots of drag racers use the Slant 6 torsion bars and no sway bar with a big block - and with skinny tires on front there's no way those cars are safe on the street (spirited driving or not). I don't race so I do think it's very important to swap in the heavier suspension and brakes with the big block. That has to be taken into consideration in anything other than a pure drag car.

Weight is a killer an any kind of racing. This is why guys stick big block in Darts instead of Imperials if they're serious about competing at the drags. It's also why SCCA racing is full of 150 hp Miatas, 240 SXs, and RX-7s instead of full size cars.


The 340 Challengers got the heavy duty suspension as part of the package. That's one reason the 383 had no chance against them on the back roads.

A street stroker 340/360 can put out the same HP/torque as a stock 426 Hemi (for about the cost of Hemi heads too) yet weighs 300 pounds less. For a full-blown race motor the big block has the advantage purely because it can be built bigger. At the 700-1,200 hp range I'm not sure the weight of the block is your biggest concern.

Troy

[Ghoste]

I had the small bars in a big block B-body many years ago and I sure didn't find it to always feel safe in "spirited" street driving.

[Mike DC]

                       
             
I don't think the soft T-bars in front are the handling problem so much as the undersized front swaybar.

The T-bar & LCA setup puts the spring pressure on the chassis pretty far inward from the wheels.  It needs the swaybar action much more than a car with coil springs mounted outside the front framerails.   

 

[Ghoste]

Whichever one affected it more, what I most recall is the attention needed over 50mph once you got into roads with a lot of turning and it wasn't fun.  It didn't feel dangerous, just not normal or relaxed the way a proper big Dodge was.  The engineers spec those components for a reason I suppose.

[Mike DC]

                                          
Yeah, the engineers weren't dummies.  Sometimes we act like we're smarter just because we know how to improve something now but we rarely see it through the appropriate eyes.  Those unibodies and suspensions were originally as stiff as the stock tires could take advantange of.  It's only modernized radial tires and less cost-cutting per car that have really allowed us to raise the bar on them.  



As for the T-bar and swaybar thing, it's all about where the T-bars are pushing up on the chassis.  In this case it's the inner pivot point of the LCA.

Think of it this way.  Imagine if we're trying to hold up the front end of the car with coil springs.  Putting a huge 2000-lb spring under the center of the K-frame is not as stable as using a pair of 1000-lb springs with one under each LCA.  Same total spring force under the front end, different effects on body roll.  
                   
                       

[elacruze]

Hm. Suspension is complicated.

Think of a cross section slice through the wheel bearings of your front hubs. Consider the contact patch of the tire, LCA pivot, engine position, etc. Now think about your rear suspension in a drag race perspective. You have all the same considerations. Traction, leverage points, center of mass, instant center etc.

The taller your tires, the more leverage they have against the LCA. Thus, when you corner the suspension will tend to lift more-steering inputs make fast changes in lift during compression which is why soft cars feel unsettled while steering in corners. Raising your trim height changes the center of mass, instant center, and increases the effective tire height in relation to LCA length.

Aluminum heads lower and reduce the center of mass of the engine. Thus, it has less leverage against the suspension and the car will roll less. Moreso for a small-block, etc.

Anti-Sway bar; think backwards. The bar can't contribute anything with one end detached-what's happening when the car rolls, is the bar tries to compress the opposite side to stay straight; that transfers high-side spring rate through the bar to the compressed side and pulls the entire center of mass lower as well by the frame mounts.

That should make it clear why generally the better a car handles, the lower it is, short tires, long control arms, light motors and stiff suspension.

Or not.

[68corazonetR/T]

      Positions to where  things connect will matter but guys the same rules apply here as when your talking cubic inches...if you start out bigger you can end up bigger. Just now were talking how rigid a car will be and how the geometry works.
           I am out of the automotive trade, for a while now but I do remember some things and  listening to some pretty smart people when I took the course.
You know when you push on a coil spring... it has a little give to it. How much it goes down with certain force. Spring Rate. With coils they can change the distance between the coils to give you a softer ride a the top of your travel. Not so with torsion bars...well maybe if they were tapered but I don't think so.
   
  What you have with a set of slant six bars is a car with a different spring rate or softer ride....it's still going to hold the car up but with more stress and a shorter life.  If there was such a thing... would you put a set in from a four cylinder?

Back to the original topic I think what chargd is saying about throwing any old 440 in.. applies with what I have. The 73 440 Had a ratio 8.20 : 1 and produced with it's four barrel                                                           280hp @ 4400 and torque is 350 @ 2400.
My 67 318 ... with a 2 barell , a ratio of 9.2 : 1 produced       230 hp @ 4400 and torque is 340 @2400
  So I figure with less money and work I can get some good bang for my buck.  But still theres no question the 440 could be built into a monster... and maybe a set of better pistons would of done wonders but now we are talking about a rebuild
I believe that my 318 has a steel crank and so it might just have some real potential.
Jack