360 vs 383

[rmchrgr]

Since I am cheap, and only run factory heads, blocks, and usually intakes, I never noticed any big weight differentials or 383 A-Body lack of handling. Have you driven a factory big block A-Body? Theoretical BS as far as I'm concerned having driven HP 383 and 340 A-Bodies as daily drivers. Never cared for a 360. To be fair the poll should have been 360 HP 4 barrel and 383 HP 4 barrel. Heck, I passed on a new factory 360 HP 4 barrel Aspen because the 273 I was running was faster. The 383 has a forged crank, neutral balance, stronger block, better flowing heads, and is just a cam change away from being high performance with all that torque. If you can't get your 360 or 383 to pull past 4,000 rpm you should not be talking High Performance. No need to equalize torque convertors or gears. No rules on the street. If you want to spend all that coin on stroker assemblies and aluminum heads, go for it. I never felt the need for any of it.

Not sure if this was directed at me but if it was, I did clearly say in one of my posts that I have not driven a big block A body so no, I do not have any direct experience with it. However, it seems to be long-standing, common knowledge in Mopar world that was indeed the case with those cars. Take that for what it's worth I guess.

You can't get around the fact that there is a decent amount of extra weight in front with a BB over a SB. The surrounding parts that support the BB also add some amount of heft (t bars for example) so it's not just the engine itself, it's more unsprung weight all around. Trying to get a heavier car with poor front-to-rear weight balance to handle is an uphill battle. That's a fact.

The guy that thought up the 383 A body was Mr. Norm. Mr. Norm was not an engineer, he was a salesman. Did he prove it could be done? Sure. Were they the terrors that he thought they would be? I don't think so since only a couple thousand BB A bodies were produced between 1967-69. From either an engineering or sales standpoint, they don't make as much sense as a hi-po small block, at least for a normal street driven application. BB A bodies were heavier, more expensive to insure, don't handle as well, got less MPG and ultimately they cost more to buy because of all the special equipment. Not hard to see why they didn't sell that well. I'll take a 340 Dart over a 383 Dart 10x out of 10x.

Also, in regards to the rpms of the 383 - I tried to get mine to rev over 4,500 just about every time I was in the car. What can I say? It just wouldn't do it. Seriously, it would barely break the tires loose unless it was on gravel. I'll reiterate that the engine was likely worn out to an extent but despite that, I know for a fact it ran about as well as it could have - it had good compression, plenty of timing and it was EFI so the fuel was pretty well managed. It really just had no stones. Nothing to do with a poor converter either since it was a 4 speed. 3.23 gears didn't help but that's what gears were in those cars when they were new. Maybe if it had bias tires it would have been easier. It cruised OK but that's about it. Like I said, pretty much a station wagon engine. The 5.7 Hemi (345 c.i.) in my 2017 Ram is a noticeably better performing engine because it gets my heavier truck moving faster than the 383 did in the lighter car.

Prior to owning my Coronet, I'd driven a few other 383-equipped cars over the years and was underwhelmed those times as well. In general, factory-spec'd hydraulic cams are not great performers no matter what engine they're in. Obviously a cam and gear swap would have woken things up but I never got around to those things before I sold the car.

Conversely, I had a '71 Dart with the original, bone-stock 318 2bbl and 2.94 gears (open) with 14" radials that would roast the tires at will. Is what it is.

 

[Darter6]

COME ON MAN ! They are all GOOD because they are MOPARS !!!! Hell even the late 80's small blocks can run good with a little tweekin'. MY vote is for the 361 B of 1964 !!!

 

[33IMP]

Not sure if this was directed at me but if it was, I did clearly say in one of my posts that I have not driven a big block A body so no, I do not have any direct experience with it. However, it seems to be long-standing, common knowledge in Mopar world that was indeed the case with those cars. Take that for what it's worth I guess.

You can't get around the fact that there is a decent amount of extra weight in front with a BB over a SB. The surrounding parts that support the BB also add some amount of heft (t bars for example) so it's not just the engine itself, it's more unsprung weight all around. Trying to get a heavier car with poor front-to-rear weight balance to handle is an uphill battle. That's a fact.

The guy that thought up the 383 A body was Mr. Norm. Mr. Norm was not an engineer, he was a salesman. Did he prove it could be done? Sure. Were they the terrors that he thought they would be? I don't think so since only a couple thousand BB A bodies were produced between 1967-69. From either an engineering or sales standpoint, they don't make as much sense as a hi-po small block, at least for a normal street driven application. BB A bodies were heavier, more expensive to insure, don't handle as well, got less MPG and ultimately they cost more to buy because of all the special equipment. Not hard to see why they didn't sell that well. I'll take a 340 Dart over a 383 Dart 10x out of 10x.

Also, in regards to the rpms of the 383 - I tried to get mine to rev over 4,500 just about every time I was in the car. What can I say? It just wouldn't do it. Seriously, it would barely break the tires loose unless it was on gravel. I'll reiterate that the engine was likely worn out to an extent but despite that, I know for a fact it ran about as well as it could have - it had good compression, plenty of timing and it was EFI so the fuel was pretty well managed. It really just had no stones. Nothing to do with a poor converter either since it was a 4 speed. 3.23 gears didn't help but that's what gears were in those cars when they were new. Maybe if it had bias tires it would have been easier. It cruised OK but that's about it. Like I said, pretty much a station wagon engine. The 5.7 Hemi (345 c.i.) in my 2017 Ram is a noticeably better performing engine because it gets my heavier truck moving faster than the 383 did in the lighter car.

Prior to owning my Coronet, I'd driven a few other 383-equipped cars over the years and was underwhelmed those times as well. In general, factory-spec'd hydraulic cams are not great performers no matter what engine they're in. Obviously a cam and gear swap would have woken things up but I never got around to those things before I sold the car.

Conversely, I had a '71 Dart with the original, bone-stock 318 2bbl and 2.94 gears (open) with 14" radials that would roast the tires at will. Is what it is.

383 Magnum was rated at 5200 rpm.
If you couldn't get your 383 past 4000, there was something seriously wrong with it.
If you couldn't get a 383 four speed to roast tires better than a 318 2bbl, there was something SERIOUSLY wrong with it. (I would guess trash valve springs, or a flat camshaft).

 

[rmchrgr]

Also - if I have the choice between a 383 and a 400 block, I'm going to build the 400. Whoever built the first 400 stroker basically rendered the 383 useless. The larger bore of the 400 is a significant advantage when built to whatever the intended degree. Beyond a faithful factory-style restoration using original, numbers matching parts, there is no logical reason to use a 383 if a 400 is available for similar money. I currently have 3-4 400 standard blocks myself so I'll never have an issue with that.

Plus, externally the 383 and 400 are the same. Put a 383 Magnum pie tin on top and no one will know you have a 512" low deck. Same thing with a 408-440" small block. See the F.A.S.T. class for proof of that.

The 438" that I built and linked to was for a friend. He was DEAD SET on using a 383. It took a lot of convincing to go the srtoker route but in the end, it would have been more money to refurbish all the stock parts - trust me on this, I priced it all out to the last penny. And unless he put a big cam in it, he was not going to have as much power as the mild stroker provided.

 

[rmchrgr]

383 Magnum was rated at 5200 rpm.
If you couldn't get your 383 past 4000, there was something seriously wrong with it.
If you couldn't get a 383 four speed to roast tires better than a 318 2bbl, there was something SERIOUSLY wrong with it. (I would guess trash valve springs, or a flat camshaft).

Probably valve springs going away, it ran fine otherwise. I sold the car last year so I'll never know. Still not a fan of 383s, they just don't do it for me.

 

[318willrun]

Probably valve springs going away, it ran fine otherwise. I sold the car last year so I'll never know. Still not a fan of 383s, they just don't do it for me.

Nice Car !!!

 

[318willrun]

Not even close, the 383 all day long

mild hopped 360 still gets walked on by a 383 magnum


bore size makes the 383 have more potential.

I have instances/circumstances where I'd choose one and the same for the other. I could make a quick list of 10 reasons/scenarios for each engine where they'd be the choice.

 

[318willrun]

Another question...
Is there a "cool" factor for one vs the other? Usually a BB brings the cool factor, but not always for the 383 (in many eyes).
For me, here is when each would be cool...

• 383 - in a Dodge "B" series Van, especially a shorty
• 360 - In a police Diplomat, especially if it still has the old cherries on top!

 

[OldmanRick]

Stay away half a day and 4 pgs. pop up...lol

To jump in for senario 1.....A well tuned 74' 360 Duster will run door to door with a 60's 383 Cuda ---3.23/3.21 gears. 14.40ish. Not bad for a heavier Duster, so in this case, i'm a 360 fan.

Now to senario 2, I'd probably still stick with the Duster 360 because of the ''mildly'' designation. At some point depending on camshaft upgrades, i feel the small block would require more gear/converter.

 

[OldmanRick]

Senario 3... i'm fine with a 11sec bracket car, so the 360 in a A body or 383 in a B is where i'd go here.

As far as senario 4, all bets are off. Really depends on the class or et needed to compete.

All that said, i think a moderate compression, mildly cammed, low rpm, 470/500'' B engine would be a blast in any A body with low 3gears and give many street miles with fairly low maintenance.

Now, if i was only 20/30yrs younger...

 

[RustyRatRod]

It's not hard to find a 100 lbs difference right on the front between a Duster with A/C and power steering and a "no A/C w/Manual steering" car with the same engine. Not many say too much about the handling in those cases.

It's such a small difference, who really gives a crap?

 

[RustyRatRod]

Also - if I have the choice between a 383 and a 400 block, I'm going to build the 400.

No other engines but the 360 and 383 have a bearing on this discussion.

 

[rmchrgr]

No other engines but the 360 and 383 have a bearing on this discussion.

OK Rusty Trombone, my bad for getting your panties all in a bunch.

 

[RustyRatRod]

OK Rusty Trombone, my bad for getting your panties all in a bunch.

Seems you're the one with that issue. I was just throwin out a friendly reminder. Too many of these threads get way sidetracked and his request was pretty clear in the beginning.

 

[69conv]

When you open the hood at the show and the distributer is in the front there is definitely a wow factor.

 

[33IMP]

It's such a small difference, who really gives a crap?

That kinda depends on the platform, imo. Saving 100 lbs on a 4800 lb C-body, big deal. Saving 100 lbs on a 2500 lb bracket car (or street car, if you can get to that weight), BIG deal!

 

[33IMP]

When you open the hood at the show and the distributer is in the front there is definitely a wow factor.

When I look under the hood of a b-body, I expect to see a big block, if I see a small block, I'm disappointed.
When I look under the hood of an A Body, I'm hoping to see a big block, if I see a small block, it's expected.

 

[RustyRatRod]

That kinda depends on the platform, imo. Saving 100 lbs on a 4800 lb C-body, big deal. Saving 100 lbs on a 2500 lb bracket car (or street car, if you can get to that weight), BIG deal!

I agree, although I was unaware we were talking about a drag race platform.

 

[33IMP]

I agree, although I was unaware we were talking about a drag race platform.

We weren't, really. I was just trying to make the point that weight savings mods make more sense on a lighter car. I'm not gonna put a set of aluminum heads on a 318 Imperial to save weight.

 

[RustyRatRod]

We weren't, really. I was just trying to make the point that weight savings mods make more sense on a lighter car. I'm not gonna put a set of aluminum heads on a 318 Imperial to save weight.

I agree 100%. But by the same token, I can put a complete aluminum top end on a 383 as well. So where are we then? Sure, you can say you can run aluminum parts on a small block and be lighter and you're right.....but what does that do to the OLD and WRONG opinion that a big block in an A body makes them nose heavy? It's just so untrue it's pathetic. Even with an all iron 440 it's untrue. The 69 factory 440 A bodies didn't handle badly at all. They had matching big block suspension components, so they were stable cars. And now someone will say something crappola stupid like, "They didn't autocross good". Well no crap. They were never built for that. It's just one stupid excuse after another to try and make the old adage "There's no substitute for cubic inches" wrong and you never will, because it ain't wrong. More cubes = more power = more weight carrying ability. No matter how you slice it, no matter what configuration you compare, the big block will win out for power every single time, as long as the builds are very similar. Bigger bores, bigger valves, bigger ports and better breathing. Yup, you can point to some 700 plus HP small blocks. But let me build a similarly equipped big block. Remember Jim Laroy? I bet there's not a small block factory iron head anywhere (excluding W2) that can flow over 700 horse power. Jim and Cody Laroy made it happen. ...and what's more, had Comp Cams not accidentally "forgotten" to turn the water on and that engine not overheated, we'd seen a big block Chrysler engine flow over 800HP through factory iron castings. A factory production small block head will never in a million years do the same thing. And before someone gets cute......NATURALLY ASPIRATED.

 

[340sFastback]

Speaking of weight, what about the weight of original AC compressors? Up high and as far forward as possible? Cast iron heavy....

Small block factory AC vs 383 no AC? No one ever says factory AC small block cars are nose heavy though.

 

[rumblefish360]

Having driven both big and small block Dusters & Magnums, I think the weight difference is not a huge thing but noticeable. Once I “Aluminumized” the engines, there’s nothing to complain about.

 

[abodyjoe]

When you open the hood at the show and the distributer is in the front there is definitely a wow factor.

only to a very select few who actually knows what that means.. even then not so much unless there are fenderwell headers involved..

 

[318willrun]

So I had a few key things in mind when I created this thread..... I'll throw one of them out there...

360 allows the choice of either 904 or 727. I am a huge fan of the 904 in A-bodies. Lighter, fits better, more room around the headers. 904 is not an option with the 383 without a very expensive adaptor.

 

[Charlie_es_cool]

So I had a few key things in mind when I created this thread..... I'll throw one of them out there...

360 allows the choice of either 904 or 727. I am a huge fan of the 904 in A-bodies. Lighter, fits better, more room around the headers. 904 is not an option with the 383 without a very expensive adaptor.

If using a 904 is an option, in the mildly hopped up scenario I might say its a tie or down to personal preference. I'm not sure if the lighter transmission and reduction in drivetrain losses completely make up for 23 extra cubic inches, but the extra room in the engine compartment will sway plenty to opt for the small block vs the big block. I would still go big block lol, but not for objective reasons.