I'm looking for idea's on replacing the lean burn ignition, intake and carb.

1978 NYB

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I'm looking for idea's on the best way and parts to replace the lean burn ignition / intake and carb. I have a completely stock 400 ci motor and plan on keeping the lower end and heads stock. I was thinking about the distributor and orange box ignition conversion kit that JEG's sells, Edelbrock Performer Intake and either a Edelbrock 600 or 750 square bore carb with an electric choke and the manifold/carb adapter plate.
 
What you just described is exactly what is done by 90% of the lean burn owners. When you order the Eddie, don't forget the Mopar throttle adapter. While you're at it throw on a new valley pan with paper gaskets.
Buy'em where you want to but I strongly suggest summit over Jegs.
 
Thanks, I thought I saw a color diagram that you posted on another thread that chucked half the emissions and other stuff that wasn't necessary during conversion. I haven't looked at Summit yet, but I will.
 
I agree about summit.

NYB, I just did the conversion on my 78. There are two mounting holes for a chrysler orange box just below the ground strap on the passenger side firewall. On my car there were two plastic plugs in the holes. The Ballast resistor is just to the right of it. I tapped into the ignition side of the resistor to power my box. One wire to the coil, two to the new distributor, and the green with red stipe is not used, grounded through the chassis. Pretty simple. When you change carb and run a spacer on the stock manifold you will probably run into clearance issues with the stock air cleaner if you were planning on using it.
 
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I'm looking for idea's on the best way and parts to replace the lean burn ignition / intake and carb. I have a completely stock 400 ci motor and plan on keeping the lower end and heads stock. I was thinking about the distributor and orange box ignition conversion kit that JEG's sells, Edelbrock Performer Intake and either a Edelbrock 600 or 750 square bore carb with an electric choke and the manifold/carb adapter plate.

Would you recommend a 600 or a 750 cfm carb based on a stock 400? I don't plan on stroking the motor or really modifying the performance.
 
Would you recommend a 600 or a 750 cfm carb based on a stock 400? I don't plan on stroking the motor or really modifying the performance.

This is by no means the final word, but with a stock motor you should be able to get by with a 600. Maybe a little better on fuel but may restrict power output at high RPM if you dare turn it much over 5k.

http://www.carburetion.com/calc.asp
 
...Edelbrock Performer Intake and either a Edelbrock 600 or 750 square bore carb with an electric choke and the manifold/carb adapter plate.

If you get a performer intake you will not need an adaptor plate, just a chrysler throttle adaptor. They adaptor plate is used to mount square bore carbs like the edelbrock to our stock spread bore manifolds. :)
 
NYB,

I don't know if it will help your car as much as mine but I just finished unhooking the 13.2miles of vacuum line and the various smog related parts and was rewarded with noticably better low to mid range performance. With a new intake and carb you should be very happy.
 
Thanks, I'm going to do the lean burn replacement distributor kit, carb and intake all at one time. Maybe it'll take the mpg from 10 to 14.
 
My money is on more like 12...

I met a person with a 1973 Newport at a local car cruise Friday night. He said he had a 400 (not original motor) and some sort of better performance cast iron heads and he said he gets 19 mpg all day long.

:shruggy:
 
Checkout these new 440/426 distributors w/ integral electronics from skipwhite on ebay. $55.50 w/ shipping. No external box, but will need different spark plug wires. I think you can use Magnum wires (junkyard), which are nice silicone and numbered for each cylinder.

I bought the small block version for my Dart, but haven't installed. I currently use the older Crane Cams XR700 on my Newport and Dart, but requires an external box. Another popular one is the Pertronix Ignitor, since no external box.

Re mileage, my Newport 383 gets 18 mpg hwy and 15 mpg in mixed commuting. In addition to electronic ignition, I have a Holley Pro-jection TBI w/ O2 sensor. However, I got 18 mpg hwy w/ the original Rochester 2 barrel carburetor and points ignition. The biggest factor is don't use a radical high-lift cam w/ overlap. Thumpers might sound cool but pollute and give terrible mileage.

440 distributor.jpg
 
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