Replacing original Carter AVS for Holley- recommendations on carb and manifold?

[Nickrc3]

I have been unsuccessful in my attempt to cure a hesitation and/or bogg on my 69' Charger R/T. The 440 c.i. engine has a fresh rebuild, 902 heads, factory intake & HP exhaust manifolds, 727 Automatic and a 3.23 Sure-Grip. I recently installed a PTC 'street hemi' torque converter to compliment the 284/484 Purple-shaft cam. It made a tremendous difference in acceleration and pull throughout the cam's RPM range, however I still have the stumble/hesitation when the pedal is mashed. Often, she'll cough and stall or just cough, then accelerate like a bat outta hell. I've been through the timing which is 24* initial/38* total - all in @ 2800 RPM's, FireCore distributor, vacuum advance disconnected, source plugged.
I'm running with the original Carter #4967S AVS installed on stock intake. Rebuilt carb very carefully - readjusted floats, secondary air valve, pump, etc. Still no relief in curing the bogg.
All literature I've acquired for this carb indicates the need to replace the metering rods with a larger number. I have no idea what the base levels are and how large to increase. Do the AFB rods fit the AVS series carbs?
Being this is a 45-year old carburetor I feel I should cut my loses and purchase a Holley, which I comfortable in tuning.
Which Holley would you recommend? I'm leaning towards a 4150 - 780 dual-feed, vacuum secondary. Are those 'Street Avenger' models recommended? Would the engine really benefit with a double pump version?
Can I utilize the stock air cleaner assembly?
Intake Manifold? I've read the MP from Summitt is a desired choice for low RPM torque, which I desire. Will this manifold and a Holley fit under the hood, utilizing the stock sir cleaner?

Thanks Guys!

[Ghoste]

AFB rods are two step and AVS ones are three.  Your choice in the Holley is a good one and I'd be tempted to try it first on the stock manifold before switching intakes.

[Kern Dog]

It is hard to go wrong with a  3310 4150 Holley 750 vacuum secondary 4 barrel. I had one on a mild 440 with a slightly smaller cam than yours, the 280/474. The car ran like a raped ape with a Performer RPM intake, that 750 and 1 7/8" headers, 727 with 3.23 gears.
I see you listed the Avenger carb. I have no personal experience with those but they look nice. A vacuum secondary carb is THE way to go with a street car that may see some dragstrip time.

[myk]

I'd start out with the 'carb first as well...

[Ghoste]

Is the rest of the car modified Nickrc3 or is it largely all stock?

edit:  I see now that it is modified

[69wannabe]

It is hard to go wrong with a  3310 4150 Holley 750 vacuum secondary 4 barrel. I had one on a mild 440 with a slightly smaller cam than yours, the 280/474. The car ran like a raped ape with a Performer RPM intake, that 750 and 1 7/8" headers, 727 with 3.23 gears.
I see you listed the Avenger carb. I have no personal experience with those but they look nice. A vacuum secondary carb is THE way to go with a street car that may see some dragstrip time.

X2!! The 3310 holley is a good carb!! I would swap the carb first and see how it runs and then the intake later. You can run a stock air cleaner with the RPM intake but you will have to run a drop base style to clear your hood and then you will have your transmission valve body linkage to consider since to got an automatic. The street avenger carbs are OK, I have had two of them but the 3310 is still a better carb to me or even the 4779 double pumper carb would be a good choice too!!

[firefighter3931]

I'd look at a proform 750 dp street series carb. You have a pretty healthy cam and it needs an agressive fuel curve....more than the current AFB can deliver.  

The vintage Edelbrock CH4B is an excellent intake manifold and works great with stock throttle/kickdown linkage and won't push the stock aircleaner into the hood. Look on ebay as these are no longer in production.


Ron

[Nickrc3]

Thanks for all the recommendations, Fellows.

Ron, is this the specific Proform #67213 you suggest:
http://www.proformparts.com/product-exec/product_id/878/nm/PROFORM_reg_STREET_SERIES_CARBURETOR_b_750_CFM_b_MECHANICAL_SECONDARY/category_id/182

With my PTC-equipped 727 TorqueFlite and Purple cam, the double pump is not an issue? Do I need an adapter plate to fit the ProForm carb onto the stock intake manifold? Can the existing accelerator cabling, brackets and kick-down linkage configuration be utilized, or do I need aftermarket items?
As mentioned, I desire to retain that 'stock' appearance with the air cleaner, therefore, searching for a CH4B intake - just not comfortable with current pricing on E-bay. $200 

Thanks again...

[firefighter3931]

Thanks for all the recommendations, Fellows.

Ron, is this the specific Proform #67213 you suggest:
http://www.proformparts.com/product-exec/product_id/878/nm/PROFORM_reg_STREET_SERIES_CARBURETOR_b_750_CFM_b_MECHANICAL_SECONDARY/category_id/182

With my PTC-equipped 727 TorqueFlite and Purple cam, the double pump is not an issue? Do I need an adapter plate to fit the ProForm carb onto the stock intake manifold? Can the existing accelerator cabling, brackets and kick-down linkage configuration be utilized, or do I need aftermarket items?
As mentioned, I desire to retain that 'stock' appearance with the air cleaner, therefore, searching for a CH4B intake - just not comfortable with current pricing on E-bay. $200 

Thanks again...

Hi Nick, yes, that is the carb. No worries with the double pumper....you have enough motor to use it 

It'll work fine with the stock manifold but you should run a 1/2in 4 hole phenolic spacer so the accelerator pump linkage clears. The spacer also helps prevent vapor lock and keeps the fuel cooler in the warm weather. 

You'll need the holley 20-7 adapter for the proper throttle linkage ratio. Stock cable & kickdown linkage will work fine. 

A company called "fabulous fabrications" makes a very nice OEM looking fuel line kit for the Holley/Proform double pumpers. Complete setup from fuel pump to duel bowl inlets. Several members here have used that kit with excellent results.


Ron

[Nickrc3]

Spent several hours of research on DodgeCharger.com yesterday, and purchased the ProForm carburetor recommended by our resident expert Firefighter 3931.
I was a little disappointed with my usual vendor, Summit Racing. After their thorough confirmation of the ad from a smaller competitor, they failed to match the offer of the identical carb fifteen dollars cheaper, free shipping & this handy little tool:

So, I called JEGS who had no problem in giving me that deal. Great people!
Don't forget two of these to achieve the proper fit with the Mopar 5/16" inverted flare nut within the fuel line:

The fuel bowl fittings installed on the new carb apparently are for a 3/8" flare nut. I didn't bother ordering the throttle post, as I figured I'd use the existing one from the Carter.


I've got a line on one of those CH4B manifolds:
. Awaiting to seal the transaction.

Lastly, kudos to Greg @ Fabulous Fabrications for informing me on the issue with the fuel bowl inlet fittings. Called him this morning to order the 'stock appearing' dual feed fuel line which rides the valve cover and extends directly down to the vapor canister. I also ordered his coil relocation bracket, to maintain that factory look.

Keep you posted on updates...

[Ghoste]

Who was the smaller competitor?

[Nickrc3]

Who was the smaller competitor?

Speed Unlimited.

[Nickrc3]

GREAT NEWS!!! No more dreaded bogg, stumble or hesitation - from dead stop, simply awesome performance 

My progress:
                   Listening closely to Firefighter 3931 or other contributors, I obtained the suggested products including the Proform 750DP carburetor, CH4B intake manifold, wires, coil w/ matching ballast resister, etc.


I located the CH4B intake on a national Craigslist search. Price was right, but required new Heli-Coils in all locations. No big deal.
After I glass-beaded, I applied a 2K epoxy primer, then shot Eastwood's High-Temp ceramic engine paint.
This product produces outstanding results. It's single-stage, and when mixed 4:1 w/ activator, results in a beautiful, rock-hard finish.

Fabulous Fabrications provided the fuel line and coil relocation bracket. One problem encountered was the hole configuration, however, I never mentioned to Greg the bracket was to be used on a CH4B manifold. It likely fits the Performer RPM manifold.


Quick work with a die grinder solved that:


Everything now installed, including the necessary throttle adaption bracket from Holley.


[imghttp://i1002.photobucket.com/albums/af150/Nickrc3/DSC02124.jpg]http://[/img]


Note the fuel line insulating cover which extends down to the vapor canister; cheap insurance to prevent fuel vapor lock. I fabricated a new 12v lead from the coil to the choke assembly, and also had to extend the negative leads to coil. New FireCore wires were then installed.

So, after a thorough check of the mechanical and electrical connections, including air/fuel fittings, I was ready to start the engine.
Once manually-primed, she fired right up and sustained a manageable idle. I immediately noticed the fuel levels through the float site glass were centered,
though did sense a strong 'rich' smell from the exhaust. Carb accepted throttle nicely.
Upon warm-up, I observed the idle mixture screws (4) were only screwed out 1.5 turns. Monitoring the vacuum gauge, I tweaked all four for peak vacuum and RPM readings. Interestingly, these adjustments had very limited range (see new thread on carb tuning). Final settings are 3/4 turns out from base. Start-up was instantaneous, even after sitting for two hours. It appears fuel remains within the bowls longer than the previous Carter carb.

My anxiety over performance was soon to be squelched. I immediately felt an improvement in the transition from idle to light acceleration. The engine sounded different, and appeared very responsive to slight depressions of the pedal. It just behaves so well accelerating from a stop light to a normal cruising speed.
Once I approached my AREA 51 proving grounds (an active industrial park of which the majority of businesses are automotive-related), I came to a complete stop in the center of the road. With the selector in Drive, the pedal was mashed to the floorboard. WOW!!! My goodness, a significant improvement!  The engine instantly responded very cleanly, loud and angry. No stumble, cough or everything - just raw acceleration.
Both tires were spinning away. Within seconds, she reached 5500 RPM and shifted into 2nd. More spin, however, fully controllable. The car continued to pull like a locomotive up into 3rd. The gravitational force with being thrown back into the seat was tremendous.  (Very soon, I hope to post a video of this activity - I just need to learn the method).

I drove around the block and returned to the burnout site observing my two 60+ feet of rubber left in the asphalt - great stuff! So, of course, I had to replicate. This time, I manually-shifted with similar results - also had an audience from the adjacent garages cheering me on with their thumbs raised. 

Well, I cannot thank Ron and others enough for their inputs and accurate assessments. I was so tired of chasing the many issues with tuning that 45-year old Carter. It's now oiled, sealed inside a bag and stored. From my years of playing with large-scale model airplane engines, I often encountered mechanical wear between metallic components, creating all sorts of problems. Remedying this usually required replacement. I suspect this may have attributed to the many deficiencies with the original carburetor.

Thanks again Guys. I do believe this completes my planned modifications to the vehicle, but who knows? Maybe a set of Stealth cylinder heads and Lucati cam???
It's an addiction...

[Charger4404spd]

Nice job! 

[firefighter3931]

Nick,

I allways enjoy reading your "Area 51" proving grounds descriptions 

Great Job and keep plugging away at the idle circuit. 



Ron

[1970Moparmann]

Great write up!

[Ghoste]

Clear, well laid out and to the point photos as well.