Posted By: 68 Roadrunner
Hesitation / Bog with new combo ??? - 08/05/10 04:05 AM
Still working the bugs out of my new 383. After sending the "stock" style Mopar Electronic ignition back to Jegs and ordering a Pertronix Flamethrower Distributor with ignitor III it is running again. It seems to run great except for a flat spot right off idle. If I really stab the throttle fast it will actually die. I'm not sure where to start because I have never really had it running perfect since I built the motor. Any suggestions...Carb? Ignition? Timing? I have tried setting the initial anywhere between 12-16 and it made no difference. I don't know what the full advance is going to. I put the lightest springs in the vacuum advance tonight and I will see if it makes any difference tomorrow.
Posted By: RapidRobert
Re: Hesitation / Bog with new combo ??? - 08/05/10 04:33 AM
check: accellerator pump shot (should have a squirt immediately on tip in)/float level/ jetting not too lean/vac leak. ported timing?
Posted By: Commando1
Re: Hesitation / Bog with new combo ??? - 08/05/10 12:37 PM
Umm...
What's on there for a carb?
Posted By: 68 Roadrunner
Re: Hesitation / Bog with new combo ??? - 08/05/10 01:48 PM
Yeah I know. I don't have a timing light that will do it so I need to get a tape for my balancer. This hesitation is right off idle so I don't think it has anything to do with the full advance...but I could be wrong. That's why I am asking! I am no tuning expert!
Posted By: Mr.Yuck
Re: Hesitation / Bog with new combo ??? - 08/05/10 02:55 PM
So did it bog before the distrib swap?
Posted By: 68 Roadrunner
Re: Hesitation / Bog with new combo ??? - 08/05/10 03:07 PM
Really hard to say. Like I said before it hasn't been running right since I got the motor done. I was running it with my 42 year old points distributor for the last couple weeks...so it didn't run perfect. It seems more noticeable now, but it could be because I am expecting it to run good and it doesn't.
Posted By: Paul_Fancsali
Re: Hesitation / Bog with new combo ??? - 08/05/10 03:18 PM
Quit worrying about initial and set the total. The initial will be Ok in most cases for starting. Put the to near 36-38 total or more on a 383. I like 40=41
Posted By: jbc426
Re: Hesitation / Bog with new combo ??? - 08/05/10 07:12 PM
"I put the lightest springs in the vacuum advance tonight and I will see if it makes any difference tomorrow."
Do you set the timing with the vacuum advance hooked up? Try disconnecting it completely. The vacuum advance is different than the mechanical advance, although they both advance the timing.
Read the info that came with the distributor. It may tell you how much mechanical advance it comes with, how to adjust it and whether or not it is easy to adjust without having to weld and file the slots.
Check for vacuum leaks. Check your float levels, power valve sizing and function, accelerator discharge nozzel size, jet sizes and idle A/F settings.
Are you running a PCV valve on this motor?
Posted By: 540challenger
Re: Hesitation / Bog with new combo ??? - 08/05/10 07:32 PM
Some guys say this is normal for Mopars???
They have no clue what they are talking about. what does it idle at in gear???
Posted By: Mr.Yuck
Re: Hesitation / Bog with new combo ??? - 08/05/10 09:28 PM
here's how I do a new set up. turn your mixture screws all the way in and then back out 1 1/4 turn. start the car. Turn the idle up to 2200rpm. Set your timing in full at 38*. bring your idle back down to 1000. turn the mixture screws out until you get the best vacuum reading. Then back the idle down to 1000 (or there about) Check your initial. If it's anywhere between 12-18 you're good. RUn it back up to 2200 and check full again. NO VAC ADVANCE. Leave that unhooked. Go for a blast. If it pings drop the timing some.
I think I may have tuned the hesitation out of the carb with the idle mixture screws. Maybe the softer springs in the dist. helped? 
This thing has a real hard time idling in gear. Idles at about 1200 in park and will barely idle in gear. Some guys say this is normal for Mopars???
