LOL, I figured you didn't. Hey I've done the same thing.
383 vs 400
- Thread starter dart67
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5/13/11 is the first post!
We just made 2017!!!
Good topic. Though I think it is settled.
We just made 2017!!!
Good topic. Though I think it is settled.
If I had each to choose from, the 400 hands down.
I had both to choose from, I built the 400 and cleaned and bagged the 440.
440outlawdart
Well-Known Member
400 all the way,stroke to 499 or 512
ir3333
Well-Known Member
i thought stock 383's were all low compression but advertised at 10:1 so you could blue print
them to the factory rating and be NHRA legal.I have never heard of stock 383 pistons sitting
above the deck but maybe some were?
..as suggested a 340 has some advantages over a big block in an A body.
them to the factory rating and be NHRA legal.I have never heard of stock 383 pistons sitting
above the deck but maybe some were?
..as suggested a 340 has some advantages over a big block in an A body.
Some used closed chamber heads. The 343 HP dual carb 383 was a holy terror in stock eliminator in about 63.
The owners of Spook's Customs in San Antonio had one in a Savoy and I actually was blessed by getting to ride in it twice during the Bun & Barrel cruise in San Antonio. That car is a sucker punch if you're not paying attention.
I THINK 68-9's did ...thats why 67 closed chambers were a no go on these ?
2011 thread revived in 2017 and again today.
400 is a MUCH underappreciated Mopar engine.
The biggest disadvantage is lack of off the shelf pistons for anything but a stock compression ratio.
Note on page one a common book HP number mismatch was given-
383 with 330/335 HP and 400 with "only" 250.
That is a gross vs net mismatch and is an incorrect comparison.
I'd bet dollars that on a dyno, the numbers would be MUCH closer.
Also most stock 383 cars in the 60's had a standard 2.94 or 3.23 (maybe even 3.55) rear gear.
OTOH most late 70's 400 cars had a 2.76 or even a 2.4x gear.
That's another unfair comparison.
I've had both and found them to be very, very similar.
(383/906head HP, and 400/452 head in the same B body car with 3.55 gears)
A point I didn't see but may have missed is the early non-HP 383 came with smaller valve 516 heads.
Almost all 400s came with 452 heads which are very similar and flow like the "HP" 906 head from the 60's.
400 is a MUCH underappreciated Mopar engine.
The biggest disadvantage is lack of off the shelf pistons for anything but a stock compression ratio.
Note on page one a common book HP number mismatch was given-
383 with 330/335 HP and 400 with "only" 250.
That is a gross vs net mismatch and is an incorrect comparison.
I'd bet dollars that on a dyno, the numbers would be MUCH closer.
Also most stock 383 cars in the 60's had a standard 2.94 or 3.23 (maybe even 3.55) rear gear.
OTOH most late 70's 400 cars had a 2.76 or even a 2.4x gear.
That's another unfair comparison.
I've had both and found them to be very, very similar.
(383/906head HP, and 400/452 head in the same B body car with 3.55 gears)
A point I didn't see but may have missed is the early non-HP 383 came with smaller valve 516 heads.
Almost all 400s came with 452 heads which are very similar and flow like the "HP" 906 head from the 60's.
Reason I reply'd is I have a 8-31-71 3614230-1 400 block and a 383 steel crank I want to use and NEED to add to my learning curve on doing this. I've been told to do this everything needs to be rebalanced and I'm wanting to use forged pistons "if available" with the 400 block.I'm planning on installing a 1/2" pick up and enlarging & chamfering the intake oil passage to D.C specs. I've owned the 400 since 1983 bought it off the man who bought the CHARGER new and know it has never been bored . It came with a cast crank 2bbl carb n a rebuildable CARTER fuel pump with blue overspray ?
It may well be the original crank, unless it's something you personally pieced together. 400s came with steel cranks all the way to the end of their production run in manual transmission trucks.
Ya it's a Frankenstein...like all my stuff ... I only added the steel crank
Indeed it would. However, get the compression the same in the 400 and use the same cam and heads as the HP 383 and it wouldn't be close either.
JDMopar
Well-Known Member
Prime candidate for a stroker crank since you're wanting forged pistons anyway! 3.75 stroke makes it a 451, 3.91 stroke makes it a 470.
Two7T3Dart
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Build a 400 to 383 specs (10:1 CR, decent cam, etc...) they perform just fine.
WEeeLL I would BUT I have a 11-6-75 4006630440-7 440 block & steel crank + 6 pack rods H.B n Flywheel with ported, polished 3751213 heads with oversize valves that I'm putting in my 70 CORONET 440. I have the # matching 727 with the 400 from the CHARGER and I'd LIKE ? to find a 72 something to put it in, POLARA MONACO DART DUSTER or maybe even a SWEPTLINE1/2 ton....or MAAAAAYBE even a F,M,J body ????. I had a 69 S.B with a 70 R.R 383 MAGUM and it SCREAMED so I'd like to use the 400 block n heads with MAYBE a STREET HEMI grind cam for it. I want to get both short blocks done and I only live about an HR from HUGHES so I'll go n pick there brains like I'm doing here with people who know more than I do about my...GOAL ?...For the 440 I'd like to get 500 RWHP in the end thru a 18 SPLINE to 4.10 30 SPLINE S60....Maybe 3.54's...aint made up my mind tho, the 4.10 is in as of now. The 440 will be a 6 pack intake ..On the 400 thinkn maybe 1/2 of that if you smell what I'm steppn in ;)
Where do all the "there's no replacement for displacement" guys go when 360s and 400s are being discussed?
...and I completely disagree about any "walking all over".
Swap nothing but the motor (I did) and see for yourself (as I did).
1970 HP 383 vs 1977 400 from a van.
In the same car with the same gears, it was hard to tell the difference.
...and I completely disagree about any "walking all over".
Swap nothing but the motor (I did) and see for yourself (as I did).
1970 HP 383 vs 1977 400 from a van.
In the same car with the same gears, it was hard to tell the difference.
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The 400 has seventeen more cubic inches than a 383. And a larger bore with less valve shrouding. With the same CR, cam, heads, intake and exhaust, the 400 will make more horsepower. I think the 400 block is also stronger.
400s are like 360s. They got a bad rap because stock they were all low compression smog motors. Build them the same as the smaller motors and the 400 is stronger than a 383, and a 360 is stronger than a 340. And a 440 is stronger than a 426 which is stronger than a 413. Again, this is assuming everything except the cubic inches is the same.
400s are like 360s. They got a bad rap because stock they were all low compression smog motors. Build them the same as the smaller motors and the 400 is stronger than a 383, and a 360 is stronger than a 340. And a 440 is stronger than a 426 which is stronger than a 413. Again, this is assuming everything except the cubic inches is the same.
17 cubes isn't much when dealing with the same stroke.
What would it take for a 400 big block to compete with a mild built 408 small block which is only 8 more cubes.
You'd be off starting your own thread, than piggy back on a dead thread, most will just continue the 383 vs 400 debate.
There really is no debate 17 cubes ain't that much and a factory 400 has a bunch of catching up to compete with a 335hp 383.
I think a 383 2 barrel engine would give a smog 400 a run for the money. lol
Technically the 400 bore has more potential, question is, are you building anything that really needs that potential, lot's are making 500+ hp with around a 4" bore.
It's what you want to build has more to do with it then is it capable cause most of these engines even the lowly 318 is capable of quite a bit.
It's what you want to build has more to do with it then is it capable cause most of these engines even the lowly 318 is capable of quite a bit.
Pretty much the engine with the most usable power and especially if the rest of the car is setup to use it should win, which sounds like 383 has the most stock potential.
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