Hesitation / Bog with new combo ???
#765704
08/05/10 12:05 AM
08/05/10 12:05 AM
|
Joined: Mar 2010
Posts: 130
Marcell, MN
68 Roadrunner
OP
member
|
OP
member
Joined: Mar 2010
Posts: 130
Marcell, MN
|
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. 
1968 Roadrunner 383 auto
.060 KB 400 domed pistons, Stealth heads, Torker intake, Holley 830, Lunati Voodoo cam 276/284, .513/.533, TCI 3500, 3.91 gears, all ARP fasteners,
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: 68 Roadrunner]
#765705
08/05/10 12:33 AM
08/05/10 12:33 AM
|
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
|
check: accellerator pump shot (should have a squirt immediately on tip in)/float level/ jetting not too lean/vac leak. ported timing?
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: Commando1]
#765707
08/05/10 08:56 AM
08/05/10 08:56 AM
|
Joined: Nov 2004
Posts: 843
Suffolk,VA
ireland383
super stock
|
super stock
Joined: Nov 2004
Posts: 843
Suffolk,VA
|
Quote:
Umm...
What's on there for a carb?
It says Holley 830 in his sig.
Check your pump shot like Robert said. You might need a different pump cam or and adjustment of the arm.
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: 68 Roadrunner]
#765708
08/05/10 09:44 AM
08/05/10 09:44 AM
|
Joined: Jan 2003
Posts: 75,004
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,004
U.S.S.A.
|
Quote:
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.
Along with setting initial you need to set full advance.
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: JohnRR]
#765709
08/05/10 09:48 AM
08/05/10 09:48 AM
|
Joined: Mar 2010
Posts: 130
Marcell, MN
68 Roadrunner
OP
member
|
OP
member
Joined: Mar 2010
Posts: 130
Marcell, MN
|
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! 
1968 Roadrunner 383 auto
.060 KB 400 domed pistons, Stealth heads, Torker intake, Holley 830, Lunati Voodoo cam 276/284, .513/.533, TCI 3500, 3.91 gears, all ARP fasteners,
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: Mr.Yuck]
#765711
08/05/10 11:07 AM
08/05/10 11:07 AM
|
Joined: Mar 2010
Posts: 130
Marcell, MN
68 Roadrunner
OP
member
|
OP
member
Joined: Mar 2010
Posts: 130
Marcell, MN
|
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.
1968 Roadrunner 383 auto
.060 KB 400 domed pistons, Stealth heads, Torker intake, Holley 830, Lunati Voodoo cam 276/284, .513/.533, TCI 3500, 3.91 gears, all ARP fasteners,
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: 68 Roadrunner]
#765714
08/05/10 03:12 PM
08/05/10 03:12 PM
|
Joined: Mar 2007
Posts: 3,277
West Coast, USA
jbc426
master
|
master
Joined: Mar 2007
Posts: 3,277
West Coast, USA
|
"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?
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: Commando1]
#765715
08/05/10 03:13 PM
08/05/10 03:13 PM
|
Joined: Mar 2010
Posts: 130
Marcell, MN
68 Roadrunner
OP
member
|
OP
member
Joined: Mar 2010
Posts: 130
Marcell, MN
|
Quote:
Quote:
It says Holley 830 in his sig.
Who the hell looks at sigs to get engine specs?
I do. I thought that is what the sig. is for.  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???
1968 Roadrunner 383 auto
.060 KB 400 domed pistons, Stealth heads, Torker intake, Holley 830, Lunati Voodoo cam 276/284, .513/.533, TCI 3500, 3.91 gears, all ARP fasteners,
|
|
|
Re: Hesitation / Bog with new combo ???
[Re: jbc426]
#765718
08/05/10 03:43 PM
08/05/10 03:43 PM
|
Joined: Mar 2010
Posts: 130
Marcell, MN
68 Roadrunner
OP
member
|
OP
member
Joined: Mar 2010
Posts: 130
Marcell, MN
|
Quote:
"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?
Yes I am running a pcv. I check the timing with the vacuum advance disconnected.
1968 Roadrunner 383 auto
.060 KB 400 domed pistons, Stealth heads, Torker intake, Holley 830, Lunati Voodoo cam 276/284, .513/.533, TCI 3500, 3.91 gears, all ARP fasteners,
|
|
|
|
|
