4-barrel conversion, Newport w/383??

Scoopy G

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Hello gents,

I am thinking about converting my 67 Newport custom to a 4-barrel setup. It currently has a 2-barrel, but it does have dual exhaust.

So, where do I find a manifold? Carburetor? Do I go aftermarket, or can I get old parts to do this conversion. I love the car, and the engine runs very well, but it would be nice to have more available power, like my '63 Riviera.

Thanks for any help, Rich in Tampa
 
I did it on a 2bbl fury 383. it ran faster but got worse mileage. I did a eddy 1405 and weiand 8008 intake. and I liked it.

look on CL for carbs $100 ish. I didn't see any 383 intakes in tampa only 440

try not to die -

- saylor
 
In '68, Chrysler put the Edelbrock DP4B aluminum intake into their Hustle Stuff (later Direct Connection and Mopar Performance) performance parts program, with a factory Chrysler part number cast into it. Think "Performer" in the current time.

The factory 4bbl on the 383 was a Carter AFB, which would equate to the Edelbrock AFB in current time. 1406 with the electric choke, I believe? Check www.edelbrock.com for the installation instructions for the Performer intake for the 383, for any extra required parts, like the extension for the existing kickdown rod on the trans linkage, possibly.

The '67 383/325 (4bbl) air cleaner was the "small circle" base plate air cleaner, as the '68 had the "Holley-size" larger hole in the base plate (as the '68 Road Runner did). You can possibly find one of the repro Road Runner air cleaners in Mopar Performance or at a swap meet. All you really need is the base plate to work with your existing air cleaner (same size filter). The other gain is the gap around the bottom of the top air cleaner part for an incognito open element air cleaner.

Use the "thick" OEM-style carb base gasket rather than the thin cardboard one supplied with the carb. You can probably find a pre-bent fuel line (fuel pump to carb) in the B-body reproduction vendors' fuel line selections.

From the power supply point near the power brake booster, you can run the electric choke wire along the cowl to a place where you can then bend it to run with an existing harness to the distributor area of the engine, along the inner valve cover. A little finesse can make it "invisible" to the unknowing eye. "Looking factory" rather than not.

In '67, the "4bbl cam", otherwise termed "Standard Cam" of the 383 4bbl (and 440/350) was expanded in use to the 383 2bbls. So, when done, you'll have pretty much the modern version of the 383/325-spec set-up. EXCEPT that in the '67 Chrysler models, the 383 4-bbl was a SINGLE EXHAUST engine, from the factory. Plymouth and Dodges got factory duals. ALL rated at 325 horsepower, though.

The Edelbrock intake and carb can be sourced from Summit Racing or similar. Look for the best pricing, even some sales every now and then. The OEM-style carb base gasket can be added later, from NAPA or possibly from the Holley parts catalog.

With the aluminum intake on my '67, I used the 440 6-pack paper intake gaskets with the factory steel valley pan intake manifold gasket in between them. Putting black high-heat silicone in the grooves of the valley pan helped it seal better, to me. Personal preference. You can re-use the existing intake manifold bolts, but be sure to put flat washers under them with the aluminum intake manifold.

There were different factory 4bb intakes each year, seemingly. I'm not sure which one might be the best, but probably suspect the '70-'71 vintage might be the better ones. There are some lists of the casting numbers online, possibly in several places.

When done, the car probably won't drive much different than it does now, EXCEPT above 3000rpm. The primary side of the carb is basically the same size as the 2bbl now is.

Other than the AFB-type carb, you can also used the Edelbrock AVS2 carb, with the more efficient annular discharge venture on the primary side.

It's all doable! Enjoy!
CBODY67
 
As noted there were a wide variety of 383-4 stock applications. I would suggest finding someone with a donor car and pulling a stock cast iron manifold and carb, that way you should be able to also acquire the air cleaner and kick down linkage. This is also a good option if you are on a budget as the used components are significantly cheaper than going all new.

Dave
 
Do yourself a favor and use a new carb. That will eliminate a huge potential disappointment when you do the swap. A Holley or Carter 600 should be fine for your application. Like everyone else said a proper Kick down linkage is critical for the life of your automatic transmission. You’ll need a longer throw for the foot feed. A good old school bike shop can re cable the accelerator cable after you measure how much more travel you require. You can always buy a new 4bbl cable now that we are out of the dark ages and they are available again.

Don’t worry about the manifold at first. Use a two to four barrel adapter - see if you like it (and it likes you - mpg) and then if you like how it runs & drives, swap over to a four barrel intake. This way you can revert back if you hate it no harm no foul of an intake swap. You’re not building a race car so don’t worry that the 2 to 4 adapter won’t give you a good idea of how it will run. It will.

Cast iron manifolds are cheep cheep cheep. I’m talking $25 to $50 tops. If you don’t know what you’re looking at an aluminum one could be a total piece of junk if not new. Look for a square bore instead of a spread bore as these are usually early (better) non emission control designs.

Good luck man. Post pics when you dig into it !!!
 
Thanks fellas, great advice all of it. I gotta think about this....
 
Commando, there are about 89K miles on the mighty Chrysler. After reading the replies, I'm wondering if it's worth the effort to do the 4-barrel conversion. My Riv with the 401 is really torquey, so there is plenty of power at the pedal. The Newport with the 2-barrel and Torqueflite is more leisurely (the cars weigh the same), but when kicked down, the 383 moves the car pretty well. I guess the question is where would I need/use any extra power? I'm not stoplight drag racing, so maybe I should enjoy the car the way it came from the factory. It does 80 all day long on the interstate.
 
Commando, there are about 89K miles on the mighty Chrysler. After reading the replies, I'm wondering if it's worth the effort to do the 4-barrel conversion. My Riv with the 401 is really torquey, so there is plenty of power at the pedal. The Newport with the 2-barrel and Torqueflite is more leisurely (the cars weigh the same), but when kicked down, the 383 moves the car pretty well. I guess the question is where would I need/use any extra power? I'm not stoplight drag racing, so maybe I should enjoy the car the way it came from the factory. It does 80 all day long on the interstate.
Leave it alone. More than enough smooth running engine to drive casually.
It's good for another 45k. Will you ever put that much on?
 
Cast iron manifolds are cheep cheep cheep. I’m talking $25 to $50 tops.
I beg to differ depending on the casting number.
I agree they were cheep cheep cheep a few years ago,but not anymore
For example;
There is a shortage of the "301" casting intake manifold and prices are creeping up.
The "301" is the last 3 digits of the 68-70 383 4bbl intake.
As we all know many Mopar musclecars were built within that time frame and are the more popular cars to this day.
It was common fare back in the day to toss the heavy lump in favor for an aluminum manifold.
Now people are doing "as delivered" or "factory original" restorations.
People restoring thier 68-70 B bodies back to O.E has brought up the demand and price.
Other web forums confirms this.
I sold my intake to a guy with a 69 Super Bee with the factory Ramcharger cold air hood package . He was putting it back to stock.
It had an old hi rise intake on the motor and the Ramcharger hood assembly was in the trunk.
He was looking for the better part of a year or more.
I got top dollar for intake and even drove to New Jersey to deliver it!! LOL!!
(It was on the way anyways,LOL!!)
 
In '68, Chrysler put the Edelbrock DP4B aluminum intake into their Hustle Stuff (later Direct Connection and Mopar Performance) performance parts program, with a factory Chrysler part number cast into it. Think "Performer" in the current time.
....

The factory 4bbl on the 383 was a Carter AFB, which would equate to the Edelbrock AFB in current time. 1406 with the electric choke, I believe?
When done, the car probably won't drive much different than it does now, EXCEPT above 3000rpm. The primary side of the carb is basically the same size as the 2bbl now is.
....
CBODY67

Thank you for this illuminating, detailed response. I too am contemplating a move to a 4 barrel carb, but am inclined against it since so much of my motor's work is all done below 3000 rpm. I'm looking at "RV" cams with this in mind. Having the excellent 2:76 rear end, I like low end torque and then cruising along at relative low rpm.

Still, having a NEW carburetor has its attractions and NEW means very likely a 4 barrel. I've not forgotten the possibility of a Rochester 2G as a new 2-barrel for Mathilda either. For the present, she's running pretty well and I have plenty to do with suspension and stub frame issues, so my resources likely will go in that direction, but THEN...
 
I beg to differ depending on the casting number.
I agree they were cheep cheep cheep a few years ago,but not anymore
For example;
There is a shortage of the "301" casting intake manifold and prices are creeping up.
The "301" is the last 3 digits of the 68-70 383 4bbl intake.
As we all know many Mopar musclecars were built within that time frame and are the more popular cars to this day.
It was common fare back in the day to toss the heavy lump in favor for an aluminum manifold.
Now people are doing "as delivered" or "factory original" restorations.
People restoring thier 68-70 B bodies back to O.E has brought up the demand and price.
Other web forums confirms this.
I sold my intake to a guy with a 69 Super Bee with the factory Ramcharger cold air hood package . He was putting it back to stock.
It had an old hi rise intake on the motor and the Ramcharger hood assembly was in the trunk.
He was looking for the better part of a year or more.
I got top dollar for intake and even drove to New Jersey to deliver it!! LOL!!
(It was on the way anyways,LOL!!)
Ok maybe just out west then. A while ago I was pricing LD4B the little brother of the awesome LD340 and I ended up w a cast iron 340 instead for $25. To me the weight savings wasn’t worth the extra 3 to 600 dollars. I did see and do see big block iron intakes for beer money out here all the time. 383 400 & 440. 440 is the king but most are cheep and the highest I think I’ve ever seen is about 200 dollars. 383 do seem fewer and farther between so you do have a point there. Now if you’re looking for a specific part number and date code then all bets are off but we’re taking a will fit conversion. To me that means any square bore that’ll fit as cheep as humanly possible. I’m just saying if you really take your time & look theyre out there and nearly free. If I was gonna pay big bucks for an iron intake I think I’d buy and an old school aluminum grind off the numbers and paint it just like we did back in the “sure it’s stock” street racer days.

I’ll try to supply you guys with all the cast iron intakes you want for $3000 each plus shipping... just give me some time to go find a cheep one to complete the transaction.:poke:
 
My Riv with the 401 is really torquey, so there is plenty of power at the pedal. The Newport with the 2-barrel and Torqueflite is more leisurely (the cars weigh the same), but when kicked down, the 383 moves the car pretty well. I guess the question is where would I need/use any extra power? I'm not stoplight drag racing, so maybe I should enjoy the car the way it came from the factory. It does 80 all day long on the interstate.

The Buick Nailhead motors, by design, have a lot of lower-pm torque. Longer stroke, smaller valves, lower "rod ratio" than the Chrysler 383 does. Add in the fact that the Riv probably has "more gear" in the rear axle, too. With the more-responsive smaller primary throttle bores of the Rocheste QJet, and it's a torque motor with throttle response.

Engines designed to FIT into vehicles of the earlier '50s car chassis usually had either compromised cylinder heads or compromised exhaust manifold designs. Which is why the Buick Nailhead heads/valves are positioned more vertically than on a small block Chevy (which is a less-wide motor, too). End result, restrictive ports and smaller valve sizes. With a lower "rod ratio", less piston dwell time at TDC, so more "yank" on the intake charge and higher port velocities as a result. Buick used "more cam" to get competitive power from the Nailhead motors. In 1960, the 401s received complaints about "rough idle" due to its "more duration cam" that year.

The 383, by comparison, has better head porting, large intake valves, higher rod ratio, and a more "normal" power curve, as a result. Similar to the small block Chevy motor, by comparison.```````````````````

Enjoy EACH motor for what it is.
Enjoy!
CBODY67
 
The Buick Nailhead motors, by design, have a lot of lower-pm torque. Longer stroke, smaller valves, lower "rod ratio" than the Chrysler 383 does. Add in the fact that the Riv probably has "more gear" in the rear axle, too. With the more-responsive smaller primary throttle bores of the Rocheste QJet, and it's a torque motor with throttle response.

Engines designed to FIT into vehicles of the earlier '50s car chassis usually had either compromised cylinder heads or compromised exhaust manifold designs. Which is why the Buick Nailhead heads/valves are positioned more vertically than on a small block Chevy (which is a less-wide motor, too). End result, restrictive ports and smaller valve sizes. With a lower "rod ratio", less piston dwell time at TDC, so more "yank" on the intake charge and higher port velocities as a result. Buick used "more cam" to get competitive power from the Nailhead motors. In 1960, the 401s received complaints about "rough idle" due to its "more duration cam" that year.

The 383, by comparison, has better head porting, large intake valves, higher rod ratio, and a more "normal" power curve, as a result. Similar to the small block Chevy motor, by comparison.```````````````````

Enjoy EACH motor for what it is.
Enjoy!
CBODY67
If you ever want to see some cool Buick wizardry look into Max Balchowski’s ol’ yellar race cars. Lots of big names sat in his road race specials. He ran the Buicks because he said the motors were so much cheeper than the Chevys. He kind of chevyized them when he souped them up kinda like what the AMC guys did in trans am where they basically tried to turn an AMC motor into a small block Chevy. Check it out I’m sure you’ll find it interesting.
 
How about 2 barrel jets? I have a reman carb that seems a little wimpy. I can floor it and not a huge response. I don’t expect much with 2.76 gear but I wonder if the jets in the carb are sized for a smaller engine?

changing plug wires tomorrow. Going to closely examine my spark plugs.
 
How about 2 barrel jets? I have a reman carb that seems a little wimpy. I can floor it and not a huge response. I don’t expect much with 2.76 gear but I wonder if the jets in the carb are sized for a smaller engine?

changing plug wires tomorrow. Going to closely examine my spark plugs.

Is it an OEM Chrysler carb for the engine or a reman carb?

When you look at the spark plugs, if the ceramic insulator is toward the tan/white color spectrum and the heat range is "ball park", and the ignition timing is reasonably close, then the jets are probably fine.

The OTHER fuel calibration point is the "main system air bleed", usually on the top of the venture cluster. From the OEM production base point, larger = leaner, smaller = richer. To go richer on that air bleed, you'll need to determine what the current size is, then solder the hole closed, and re-drill the hole to a smaller size. Seems like the HP Books "Rochester Carburetor" book tells how to do that, using the area of the opening to do the math from?

In a Holley carb seminar, the engineer said that to determine if the then-current calibration was too rich or too lean, to use your finger to plug the particular air bleed up and see how the rpm reacted. If it was "good", the rpm would just drop as that fuel supply side would go full -rich. If it was lean, as the calibration became "full--rich", it would first speed up a bit and then slow down as it then went full-rich. This is one way to do the idle fuel mixture adjustments, but would probably work on the main system bleeds too, if the engine was at, say, 2000rpm in "P"? And, of course, you'll need to consult the FSM to ensure which air bleed is which.

Another way to do the experimentation is to use very thin wire to insert into the bleed, temporarily. The smaller the better. Just put a hook on the top end to hold it with!

Keep us posted,
CBODY67 ,
 
Is it an OEM Chrysler carb for the engine or a reman carb?

When you look at the spark plugs, if the ceramic insulator is toward the tan/white color spectrum and the heat range is "ball park", and the ignition timing is reasonably close, then the jets are probably fine.

The OTHER fuel calibration point is the "main system air bleed", usually on the top of the venture cluster. From the OEM production base point, larger = leaner, smaller = richer. To go richer on that air bleed, you'll need to determine what the current size is, then solder the hole closed, and re-drill the hole to a smaller size. Seems like the HP Books "Rochester Carburetor" book tells how to do that, using the area of the opening to do the math from?

In a Holley carb seminar, the engineer said that to determine if the then-current calibration was too rich or too lean, to use your finger to plug the particular air bleed up and see how the rpm reacted. If it was "good", the rpm would just drop as that fuel supply side would go full -rich. If it was lean, as the calibration became "full--rich", it would first speed up a bit and then slow down as it then went full-rich. This is one way to do the idle fuel mixture adjustments, but would probably work on the main system bleeds too, if the engine was at, say, 2000rpm in "P"? And, of course, you'll need to consult the FSM to ensure which air bleed is which.

Another way to do the experimentation is to use very thin wire to insert into the bleed, temporarily. The smaller the better. Just put a hook on the top end to hold it with!

Keep us posted,
CBODY67 ,
Thanks for that information. I have a reman BBD.
 
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