383 Magnum 4 barrel Holly Carb tuning

[ChargerDude]

Hi.

I'm a newbie and need some tuning help. I'm going to first check the ignition timing using an inductive timing light and when that is ok, then tune the carb starting with the idle. I'm starting with the idle since it has stalled a couple of times while at a stop sign/red light...so I want to get the best setup there. What rpm at idle should I look at or do I just try to get the highest vacuum reading while idling (assuming it has warmed up enough of course.) I also know that the idle tuning needs to get tweaked as the idle screw was pretty much all the way back.

Let me know if I'm on the right track or way off please...otherwise, I might just take this to a garage and have my car hooked up to a computer and get the pros to do it.

Lastly, does anyone know where I can download a free 1969 dodge service/repair manual. (I'd like to know more about the default specifications for tuning from the manufacturer too.)

Thanks.

 

[ChargerDude]

Can somebody help me with this general tuning question please?

Thanks

 

[Revhendo]

Dude, stock motor? Cam? Headers? Whatcha' got?
The basics are to set total timing (mechanical) then go after the carb.

 

[Meep-Meep]

And I'd like to add....Are you running points? Set dwell first then timing.

Basic carb settings: Idle stop screw should be 1-1.5 turns in from the throttle blades lightly seated in the bores and the idle mixture screws 2-2.5 turns out. Also check/adjust float level.

 

[ChargerDude]

Thanks for the reply and I apologize for my kindergarten knowledge on this, but bear with me. It has a 383 magnum rebuilt to stock specs (i.e. ~330 - 335 hp), headers for sure, don't know the cam. This is a 69 charger that the guy I bought it from wanted to keep it running to the original specs where possible. The car runs so smooth and purrs. On the road test, there were no hiccups while driving at 40 nor 60 as those are my 2 main driving speeds (city and highway). My only problems were that it idled to a stall once and to an almost stall once. (i know that is an idle speed issue, but I wanted to learn more on how to tweak myself rather than going to a garage with a dyno and fuel exhaust equipment.)

Does this help or do you need more? It has a 727 auto.

What do you mean about mechanical timing? My buddy has an inductive timing light and he said that we should confirm that before touching the carb...is that what you meant.

Thanks.

 

[ChargerDude]

Thanks.

My knowledge is primitive. What do you mean by points? Sorry if that is a dumb question.

 

[68ChargerAG]

Thanks.

My knowledge is primitive. What do you mean by points? Sorry if that is a dumb question.

He means does the distributor have points still or has it been converted over to electronic.

I would listen to your buddy and verify the timing first. If you have points they do require regular adjustment because they get worn down so your gap closes and timing gets later and later over time. Then verify carb settings as per Meep's suggestions.

 

[68ChargerAG]

If you have electronic ignition you will see something that looks like the orange controller on the firewall as in this pic. (yours could be a different color though). If you have points you will not have one.

 

[ChargerDude]

I have an electronic ignition. Once the timing is verified, I'm assuming that I set the idle mixture first (using the idle mixture screw(s) and a vacuum gauge, followed by the idle speed. If I'm correct, what (idle speed) rpm should I be looking at once the car has warmed up..if not what step did I miss.

Thanks for everyone's response.

 

[68ChargerAG]

Start with mixture screws each at 1.5 turns out from seats, then adjust each equally small amounts in direction to optimize vac.

600 RPM for auto and 650 RPM for standard trans.

 

[ChargerDude]

Thanks 68ChargerAG. I have an appt with my Buddy next weekend to do this stuff, but I'll have to get my vacuum gauge first. I'll keep the 600 rpm (auto for me) in mind. B.T.W. I like the shot of your engine area, very clean and well done. I'm impressed and learning to appreciate all the work involved more and more with these classics.