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Old 05-09-2016, 08:08 AM   #1
64stpside
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My 64 needs your help.....

Hey guys, Ive been working and working on this truck to get her going again and friday night I made another test drive but didn't make it more than a block away and had to come back home. It was popping through the carb and was very sluggish on acceleration. The truck has a late 70s 305 with a 4 barrel carb. I have installed a rebuilt mid to late 70s quadrajet, changed the intake gaskets and put a skip white racing HEI distributor w/adjustable vacc advance about a week ago. The timing was set to 10 deg with vac hose undone, just to start. I'm on manifold vac. When I got back, I set the timing back down to 6 deg but it seemed to run rougher. Then I started pushing the gas pedal down about 1/2 way over and over real quick and it wanted to die. Give it 1 good hit and it does o.k.
What I can't figure out is do I have a fuel or ignition issue? The only thing I haven't checked is my fuel pressure (I'll do that tonight). If my fuel pressure is good, what should I check next?
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Old 05-09-2016, 09:32 AM   #2
63burban
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Re: My 64 needs your help.....

Check the rubber fuels lines, if they are original to the truck they may be collapsing when the engine calls for fuel.
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Old 05-09-2016, 10:09 AM   #3
64shortbox
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Re: My 64 needs your help.....

64stpside
If you didn't have this problem before installing your Skip White racing distributor I would change out your distributor. There's a reason a Skip White distributor is $39.50 and a Mallory or Accel distributor is around $200.00 a friend of mine bought one of those inexpensive distributors and had the exact same problems you are having. He spent the money and bought a good Mallory and had no more problems.

Another thing I learned when setting the timing on a motor I plug the ported vacuum to the distributor hook my vacuum gauge to a manifold vacuum port and rotate the distributor back and forth until I get the highest manifold vacuum I can at idle. I then take the vehicle out and romp on it. If I hear any pinging at all I retard the distributor until the motor quits pinging under full load throttle. I had a 71 Stage 1 GS Riviera that timing this way made a HUGE difference in power & performance but on a 73 Tornado it put me exactly at the specified setting. On my 64 C-10 with a 350 I'm about 4 degrees advanced from the factory specs. Again I would install a known good distributor before going much farther and see if your truck runs any better.
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Old 05-09-2016, 10:14 AM   #4
64stpside
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Re: My 64 needs your help.....

I made up new hard line from the tank to the fuel pump and from the pump to the carb when I installed a new gas tank.

Some things I was told to check from some buddies this morning:
1. check the firing order/check for swapped plug wires
2. change to ported vacuum
3. start at 0 deg initial timing and work my way up.

If it's not a firing order issue, they think the manifold vacuum + the 10 deg initial timing is causing the issue as running ported vacuum will cause the advance to come on with the throttle. Plus having no egr will cause me not to be able to boost the initial timing as much.
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Old 05-09-2016, 10:24 AM   #5
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Re: My 64 needs your help.....

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Originally Posted by 64shortbox View Post
64stpside
If you didn't have this problem before installing your Skip White racing distributor I would change out your distributor. There's a reason a Skip White distributor is $39.50 and a Mallory or Accel distributor is around $200.00 a friend of mine bought one of those inexpensive distributors and had the exact same problems you are having. He spent the money and bought a good Mallory and had no more problems.

Another thing I learned when setting the timing on a motor I plug the ported vacuum to the distributor hook my vacuum gauge to a manifold vacuum port and rotate the distributor back and forth until I get the highest manifold vacuum I can at idle. I then take the vehicle out and romp on it. If I hear any pinging at all I retard the distributor until the motor quits pinging under full load throttle. I had a 71 Stage 1 GS Riviera that timing this way made a HUGE difference in power & performance but on a 73 Tornado it put me exactly at the specified setting. On my 64 C-10 with a 350 I'm about 4 degrees advanced from the factory specs. Again I would install a known good distributor before going much farther and see if your truck runs any better.
When I got the truck the distributor was junk (hei,with no advance at all). My buddy at work has a skip white in his 67 stepside (built 350) and it runs great. I'm not convinced the distributor is the issue yet. Was also told the adjustable advance was possibly set too high, I haven't messed with that yet. I like your tuning method and will try that once I sort all the other stuff out.
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Old 05-09-2016, 02:18 PM   #6
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Re: My 64 needs your help.....

Tell us a little more about the engine. Has it ever been rebuilt? Popping through the carb is a classic symptom of a worn cam or misadjusted valves. It could be the firing order or timing too. You might try adjusting the timing by ear in case your balancer has slipped or something. I have never had a distributor partially run. It is either dead or working. I have 5 Skip White distributors with no failures yet. You can get a dud with any brand.
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Old 05-09-2016, 02:51 PM   #7
64stpside
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Re: My 64 needs your help.....

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Originally Posted by cadillac_al View Post
Tell us a little more about the engine. Has it ever been rebuilt? Popping through the carb is a classic symptom of a worn cam or misadjusted valves. It could be the firing order or timing too. You might try adjusting the timing by ear in case your balancer has slipped or something. I have never had a distributor partially run. It is either dead or working. I have 5 Skip White distributors with no failures yet. You can get a dud with any brand.
No history on the engine. The popping is not happening one right after another it popped 2 or 3 times and the throttle response was very bad in the block I drove it so I'm not sure it's a worn cam lobe.

I need to back up a bit. I drove the truck about a 1/2 mi down the road when I bought it as it had a VERY VERY worn out mr gasket floor shifter....lol.
When I started going through the truck I was replacing a lot of parts as I didn't know the age of them. The distributor I said had no vacuum advance was one I got not knowing the condition but it was cheap (lesson learned). The truck never popped through the carb before but it still wasn't right. Maybe the old distributor was in better shape than I thought...
The truck was brought home on a trailer and I have been working on it since
last summer and am just now trying to get it out for the 1st time.
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Old 05-09-2016, 04:29 PM   #8
geezer#99
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Re: My 64 needs your help.....

You might need to verify your timing marks.
http://www.crankshaftcoalition.com/w...op_dead_center

Once that's done then put some timing in that smog 305.
Start at 14 initial.
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Old 05-09-2016, 04:43 PM   #9
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Re: My 64 needs your help.....

man. sounds like you have it worse than I do. But, I do believe an open ported vacuum port was my driveability issue the other day. I didnt however have the popping back thru the carb.

Most of the guys here that are used to these engines would probably have no problem with the troubles we are having. But for me, not knowing anything about them, its a booger. make a change. go to the internet for help. make a change. back to the internet for help. the struggle is real.

Good luck.
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Old 05-09-2016, 06:28 PM   #10
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Re: My 64 needs your help.....

Quote:
Originally Posted by geezer#99 View Post
You might need to verify your timing marks.
http://www.crankshaftcoalition.com/w...op_dead_center

Once that's done then put some timing in that smog 305.
Start at 14 initial.
This. ^^^^

Try 14 degrees initial (vacuum advance unhooked and capped at carb, engine running at idle, warmed up, no choke). Take the test drive with vacuum advance still unhooked. If it cures the popping, then it's a timing problem. You can always back it off if you hear pinging.

Once we sort out what the base timing needs to be for your engine, we can re-introduce your vacuum advance.

I also agree with checking and rechecking firing order (plug wire routing)! And confirm TDC.

Every engine is different. What worked for one guy may not work for you. And giving advice in a forum is very difficult since there is a standard set of troubleshooting techniques one must run through each time a problem like this crops up.
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Old 05-09-2016, 07:58 PM   #11
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Re: My 64 needs your help.....

I have the same low priced ebay hei distributers in at least 4 or 5 of my cars and trucks and never had a problem with any of them ever !!
I never use a timing light to set the timing on anything I own .
your rebuilt carb could possibly be a problem ?
or trying to set the timing to a certain degree # could be a problem also .
I have never had any luck setting timing with a timing light .
what the book calls for the timing to be
most of the time will make the motor run like crap.
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Old 05-09-2016, 09:48 PM   #12
cableguy0
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Re: My 64 needs your help.....

Quote:
Originally Posted by 60chevyjim View Post
I have the same low priced ebay hei distributers in at least 4 or 5 of my cars and trucks and never had a problem with any of them ever !!
I never use a timing light to set the timing on anything I own .
your rebuilt carb could possibly be a problem ?
or trying to set the timing to a certain degree # could be a problem also .
I have never had any luck setting timing with a timing light .
what the book calls for the timing to be
most of the time will make the motor run like crap.
Consider yourself lucky with the distributors. Timing needs to be set with a timing light. Adjusting timing by "ear" is a joke and you will never have your engine running at full potential. Forget the factory service manual. Those numbers are for emissions and safety. A small block chevy generally will like between 12-18 advance at idle and 34-38 degrees advance total timing all in by 3k rpm depending on the engine specs. Add another 10 or so for vacuum advance and you end up close to 50 degrees will cruising down the road.
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Old 05-10-2016, 08:59 AM   #13
64stpside
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Re: My 64 needs your help.....

lol........guys......I had #6 & #8 plug wires swapped at the distributor!!! Could have sworn I had it right before. I do have another question that's been beat to death. I had it on manifold vacuum and was told to change to ported. When I did that I could NOT get rid of the black smoke not matter what. I even had the mixture screws out only 1 turn. Set the initial timing at 4 to start then to 6 and it's at 8 now and that didn't help. I know I've been told to crank it up but have also been told that due to no egr vale, I will get pinging due to no exhaust gas to cool the charge.My understanding is that ported was done for emissions.......period......but makes the motor run like crap. My question is, if you have a carb issue, will going to manifold vacuum cover up the symptoms? I want to make sure my carb is right and I not using manifold vacuum to make things work.
Regardless of my carb being an issue, I'm going back to manifold vacuum tonight unless someone can give me a reason not to.

From another site about ported vs manifold from a GM engineer:

......(regarding ported vac) "This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it."
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Old 05-10-2016, 09:06 AM   #14
64stpside
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Re: My 64 needs your help.....

Quote:
Originally Posted by C1ph3r View Post
man. sounds like you have it worse than I do. But, I do believe an open ported vacuum port was my driveability issue the other day. I didnt however have the popping back thru the carb.

Most of the guys here that are used to these engines would probably have no problem with the troubles we are having. But for me, not knowing anything about them, its a booger. make a change. go to the internet for help. make a change. back to the internet for help. the struggle is real.

Good luck.
Last time I had mech advance dizzys was when I have my 73 AMX (I miss that car!!!) I got into foxbody mustangs (still got my 93 gt with 393 stroker) and that's WAY easier to do (pull the spout connector, set the initial, reattach the connector and let the computer take it from there).
Everyone has been great on here and we'll get 'em right......just be patient. I got so mad sat night I wanted to sell it.....lol.
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Old 05-10-2016, 09:14 AM   #15
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Re: My 64 needs your help.....

Using manifold vac will help your carb run right. With manifold vac hooked up, your idle increases and then you can turn it back down and get your carb idling on the idle circuit and not the smoky black power circuit. It all has to do with the transition slot.
There's a section in here about that.
http://www.crankshaftcoalition.com/w...EI_distributor
It talks about a holley but yours is the same.
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Old 05-10-2016, 10:43 PM   #16
64stpside
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Re: My 64 needs your help.....

Quote:
Originally Posted by geezer#99 View Post
Using manifold vac will help your carb run right. With manifold vac hooked up, your idle increases and then you can turn it back down and get your carb idling on the idle circuit and not the smoky black power circuit. It all has to do with the transition slot.
There's a section in here about that.
http://www.crankshaftcoalition.com/w...EI_distributor
It talks about a holley but yours is the same.
Runs MUCH better now. No black smoke at all. Initial is still at 8 and throttle is nice and crisp. I didn't get to drive it yet but hopefully when I do, I can get the initial higher. I still need to dial in the mixture screws and get the total timing set but need the tools to measure everything.
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