Author Topic: Sudden miss has developed  (Read 11631 times)

Offline Irish_Alley

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Re: Sudden miss has developed
« Reply #15 on: June 29, 2010, 03:39:33 pm »
Its supposed to be a 4 or so
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Offline SUX2BU99

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Re: Sudden miss has developed
« Reply #16 on: June 29, 2010, 05:02:52 pm »
4 degrees? Or 4:00 position? I know stock timing is about 4 degrees but usually it gets bumped to at least 10 for some better response and bottom-end.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline SUX2BU99

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Re: Sudden miss has developed
« Reply #17 on: June 29, 2010, 05:20:38 pm »
I just gave it a twist and took it for a spin. Running so much better now. So I'm not sure what the deal is then with my timing. I know when my cam and heads were put in, my mechanic said he wasn't sure which of the 2 positions that the timing tab was supposed to go back on. Maybe he got the wrong one? He said he figured it out but maybe not. My tab is at about the 2:00 spot on the timing cover. Fingers crossed that I won't experience the missing and shuddering that seemed to come and go, but it's behaving much better with the distro twisted somewhere back to where it used to be.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Irish_Alley

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Re: Sudden miss has developed
« Reply #18 on: June 30, 2010, 12:03:49 am »
4:00 is about the area I would think that the tab should go about 2 o’clock on the balancer
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline SUX2BU99

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Re: Sudden miss has developed
« Reply #19 on: June 30, 2010, 10:25:06 am »
Okay, I see. The twist made it run better but it's still missing and doing some of it's thing (sigh). I think I'll have to pull all the plugs and see what's up.

What gets me is the thing were if I stomp on it, it will be all funny until about 4000 RPM and then rip like usual. So I'm thinking either:

a) a fuel blockage is being bypassed by the pressure of the pump, which increases with RPM and eventually just builds enough pressure (or suction) to overcome whatever is impeding flow. But I would think this would show up at all times at lower RPM's and not intermittently

b) a fouling plug, failing plug wire or corroded/burnt contact inside the distributor is provding erratic spark delivery at lower RPMs (and lower spark voltages) but at higher RPM, the voltage increase is enough to blow past whatever the problem is. I know electronics and heat do not mix so often an erratic electrical or spark issue can be heat-triggered and it's hard to know when or where it's going to act up

 ??? ???
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Grim 82

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Re: Sudden miss has developed
« Reply #20 on: June 30, 2010, 11:30:10 am »
10 years is a long time to run a set of wires.
Give a man a gun, and he might rob a bank. Give a man a bank, and he might rob the world.

Offline SUX2BU99

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Re: Sudden miss has developed
« Reply #21 on: June 30, 2010, 12:25:21 pm »
I know that sounds like a very long time, and in a daily driver it would be. These wires are quality pieces and weren't used all that terribly much. The truck was rebuilt as a nice day driver and a toy so it wasn't used and abused daily. Even still though, I guess things like wires do deteriorate over time.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline topp

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Re: Sudden miss has developed
« Reply #22 on: June 30, 2010, 01:07:53 pm »
I know that sounds like a very long time, and in a daily driver it would be. These wires are quality pieces and weren't used all that terribly much. The truck was rebuilt as a nice day driver and a toy so it wasn't used and abused daily. Even still though, I guess things like wires do deteriorate over time.

The age alone indicates dried out insulation, amongst other things with wires that old.  EVERY wire manufacturer would tell you they should be changed well before 10 years REGARDLESS of usage.
'90 Suburban TBI 350

Offline TexasRed

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Re: Sudden miss has developed
« Reply #23 on: June 30, 2010, 05:40:02 pm »
I dunno. I've replaced wires older than that before and it was running fine. Parts store wires are only like $20, worth a try?

Offline topp

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Re: Sudden miss has developed
« Reply #24 on: June 30, 2010, 09:05:56 pm »
When all else fails, back to basics.
Cap, rotor, plugs, wires....
'90 Suburban TBI 350

Offline SUX2BU99

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Re: Sudden miss has developed
« Reply #25 on: July 05, 2010, 12:51:53 pm »
I may try replacing the fuel pump. It's old, and stock. Just wondering if I should stick with stock capacity or go wtih an 80 GPH.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.