having some ignition problems....
Thread Starter
Racer
Joined: Sep 2002
Posts: 402
Likes: 0
From: Kingsport TN
having some ignition problems....
heres the deal....
my car, when it accelerates, its strong, until about 2500, then hesitates and then pulls... is this the vaccum advance opening, creating too advanced timing to quickly?
also, when it gets to around 4000 or so rpms, the motor starts chugging like its losing fire, only on wide open throttle....
possibly a fuel pump problem? or ignition related?
im going to get a timing light tomorrow to get everything sorted out, its driving me crazy....
btw, 79 with hei, recurve kit, accel super coil and wires, speed demon 750 carb
the coil is good, i checked it with another one, still the same problem
please help....
btw, my fuel pressure gauge on the line says about 10psi or so idling at about 700 rpms, is this too much?
[Modified by SharkBit, 4:30 AM 4/28/2003]
my car, when it accelerates, its strong, until about 2500, then hesitates and then pulls... is this the vaccum advance opening, creating too advanced timing to quickly?
also, when it gets to around 4000 or so rpms, the motor starts chugging like its losing fire, only on wide open throttle....
possibly a fuel pump problem? or ignition related?
im going to get a timing light tomorrow to get everything sorted out, its driving me crazy....
btw, 79 with hei, recurve kit, accel super coil and wires, speed demon 750 carb
the coil is good, i checked it with another one, still the same problem
please help....
btw, my fuel pressure gauge on the line says about 10psi or so idling at about 700 rpms, is this too much?
[Modified by SharkBit, 4:30 AM 4/28/2003]
Thread Starter
Racer
Joined: Sep 2002
Posts: 402
Likes: 0
From: Kingsport TN
Re: having some ignition problems.... (Jack71)
no vaccum leaks
i though maybe the transition circuits might have some crud in them or something??
when wide open it doesnt do this.... except the high rpm miss, it did that with my old carb though
i though maybe the transition circuits might have some crud in them or something??
when wide open it doesnt do this.... except the high rpm miss, it did that with my old carb though
Drifting
Joined: Mar 2003
Posts: 1,608
Likes: 3
From: Canberra AUSTRALIA
St. Jude Donor '05-'06
Re: having some ignition problems.... (SharkBit)
Search the forum. There have been several posts over the last month related to your situation.
These are common symptoms to what other people had. Including me. Haven't got around to solving mine yet.
Good luck.
:steering:
These are common symptoms to what other people had. Including me. Haven't got around to solving mine yet.
Good luck.
:steering:
Melting Slicks
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
Re: having some ignition problems.... (stingry)
Did you check your plugs, they will give a good indication on what's going on. BTW are you using platinum plugs...if so they may be your problem.
Thread Starter
Racer
Joined: Sep 2002
Posts: 402
Likes: 0
From: Kingsport TN
Re: having some ignition problems.... (mvftw)
nope, just plain old ac delcos
could it be a power valve problem? i had a bad backfire the other night in the garage,
it didnt do this until i did a jet change in my carb, it was wayyyyyy too rich
also it only does it at partial acceleration and at about 2k
could it be a power valve problem? i had a bad backfire the other night in the garage,
it didnt do this until i did a jet change in my carb, it was wayyyyyy too rich
also it only does it at partial acceleration and at about 2k
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Race Director
Joined: Dec 2000
Posts: 10,896
Likes: 2
From: CO
Re: having some ignition problems.... (SharkBit)
Backfire...wouldn't that indicate that the fuel was not ignited in the combustion chamber and went into the exhaust then light up ?
I would assume that means an ignition problem. Maybe the ignition module?
I would assume that means an ignition problem. Maybe the ignition module?
Thread Starter
Racer
Joined: Sep 2002
Posts: 402
Likes: 0
From: Kingsport TN
Re: having some ignition problems.... (flood)
module is fine, had it checked, course that dont mean anything
its really confusing, my dad knows a lot about cars, but he's too lazy to help me, im really :mad right now....
oh well
its really confusing, my dad knows a lot about cars, but he's too lazy to help me, im really :mad right now....
oh well
Team Owner
Joined: Feb 2003
Posts: 30,183
Likes: 313
From: Lake Norman NC
Re: having some ignition problems.... (SharkBit)
hey man, i'm going through the same problem...i finally got my car timed right on the money at 12 initial...and also found out that i had NO VACUUM ADVANCE. get a new vacuum advance..their like 7.99...it should help it alittle. other than that....sounds like you need your carb tuned some more.
Instructor
Joined: Nov 2002
Posts: 228
Likes: 0
Re: having some ignition problems.... (SharkBit)
Check the float level in both bowels. Does this carb have vac sec. if it does you may be opening the to early. If this engine is not really hopped (9.5 compression headers and 373 rear gears ) The carb is a little large, 600 or 650 may work better.
Thread Starter
Racer
Joined: Sep 2002
Posts: 402
Likes: 0
From: Kingsport TN
Re: having some ignition problems.... (Perfomer)
thanks guys, im going to put in the old jets, buy some sec. springs and a jet kit, tune on it a little
im just not the type to leave well enough alone, hehehe
im just not the type to leave well enough alone, hehehe
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Re: having some ignition problems.... (SharkBit)
Hi
Had something simmilar on my 68 big block , when I bought it.
When stepping on the pedal and shifting up fast, before getting to 3rd gear, the car bogged and lossed all power nearly back to idle for 3 to 5 sec, than came back.
It was the secondary float level of my HOLLEY double pumper being too low.
Adjusted it and all was fine.
Good luck Gunther
Had something simmilar on my 68 big block , when I bought it.
When stepping on the pedal and shifting up fast, before getting to 3rd gear, the car bogged and lossed all power nearly back to idle for 3 to 5 sec, than came back.
It was the secondary float level of my HOLLEY double pumper being too low.
Adjusted it and all was fine.
Good luck Gunther